Remove non-working png hack.

26 files changed, 31 insertions, 24425 deletions

diff --git a/configure.in b/configure.in
index 0dd4d03..b197fb0 100644
--- a/configure.in
+++ b/configure.in
@@ -285,10 +285,15 @@ dnl Check for sndfile
 dnl ======================
 PKG_CHECK_MODULES(SNDFILE, sndfile >= 1.0.21)
 
+dnl ======================
+dnl Check for libsamplerate
+dnl ======================
+PKG_CHECK_MODULES(SAMPLERATE, samplerate >= 0.1.7)
+
 #dnl ======================
 #dnl Check for libpng
 #dnl ======================
-#PKG_CHECK_MODULES(PNG, libpng >= 1.2)
+PKG_CHECK_MODULES(PNG, libpng >= 1.2)
 
 dnl ======================
 dnl Check for zlib
diff --git a/lv2/Makefile.am b/lv2/Makefile.am
index ff543b6..a91b1c5 100644
--- a/lv2/Makefile.am
+++ b/lv2/Makefile.am
@@ -7,7 +7,7 @@ AM_CPPFLAGS = -I$(top_srcdir)/src -I$(top_srcdir)/plugingui \
 	-I$(top_srcdir)/include $(SNDFILE_CXXFLAGS) \
 	$(PTHREAD_CFLAGS) $(EXPAT_CFLAGS) $(LV2_CFLAGS) \
 	$(PLUGIN_GUI_CFLAGS) -DX11 $(SSEFLAGS)\
-	-DUSE_THREAD
+	-DUSE_THREAD $(SAMPLERATE_CFLAGS)
 
 plugindir = $(prefix)/lib/lv2/drumgizmo.lv2
 plugin_LTLIBRARIES = drumgizmo.la
diff --git a/plugingui/Makefile.am.plugingui b/plugingui/Makefile.am.plugingui
index 09ac9a4..3de830d 100644
--- a/plugingui/Makefile.am.plugingui
+++ b/plugingui/Makefile.am.plugingui
@@ -29,17 +29,7 @@ PLUGIN_GUI_SOURCES = \
 	$(top_srcdir)/plugingui/progressbar.cc \
 	$(top_srcdir)/plugingui/verticalline.cc \
 	$(top_srcdir)/plugingui/resource.cc \
-	$(top_srcdir)/plugingui/resource_data.cc \
-	$(top_srcdir)/plugingui/png/png.c \
-	$(top_srcdir)/plugingui/png/pngerror.c \
-	$(top_srcdir)/plugingui/png/pngmem.c \
-	$(top_srcdir)/plugingui/png/pngread.c \
-	$(top_srcdir)/plugingui/png/pngget.c \
-	$(top_srcdir)/plugingui/png/pngtrans.c \
-	$(top_srcdir)/plugingui/png/pngrutil.c \
-	$(top_srcdir)/plugingui/png/pngset.c \
-	$(top_srcdir)/plugingui/png/pngrio.c \
-	$(top_srcdir)/plugingui/png/pngrtran.c
+	$(top_srcdir)/plugingui/resource_data.cc
 
 PLUGIN_GUI_LIBS = $(X11_LIBS) $(PTHREAD_LIBS) $(PNG_CFLAGS) $(ZLIB_LIBS)
 
diff --git a/plugingui/image.cc b/plugingui/image.cc
index 817fe05..cba27fc 100644
--- a/plugingui/image.cc
+++ b/plugingui/image.cc
@@ -37,9 +37,6 @@
 #include "resource.h"
 // http://blog.hammerian.net/2009/reading-png-images-from-memory/
 
-#define PNG_PREFIX(x) dg_##x
-//#define PNG_PREFIX(x) x
-
 typedef struct {
   size_t p;
   size_t size;
@@ -48,10 +45,10 @@ typedef struct {
 
 static void dio_reader(png_structp png_ptr, png_bytep buf, png_size_t size)
 {
-  data_io_t *dio = (data_io_t *)PNG_PREFIX(png_get_io_ptr(png_ptr));
+  data_io_t *dio = (data_io_t *)png_get_io_ptr(png_ptr);
 
   if(size > dio->size - dio->p) {
-    PNG_PREFIX(png_error(png_ptr, "Could not read bytes."));
+    png_error(png_ptr, "Could not read bytes.");
   }
 
   memcpy(buf, (dio->data + dio->p), size);
@@ -118,7 +115,7 @@ void GUI::Image::load(const char* data, size_t size)
   const char *header = data;
 
   // test for it being a png:
-  if(PNG_PREFIX(png_sig_cmp((png_byte*)header, 0, 8))) {
+  if(png_sig_cmp((png_byte*)header, 0, 8)) {
     ERR(image, "[read_png_file] File is not recognized as a PNG file");
     setError(0);
     return;
@@ -126,7 +123,7 @@ void GUI::Image::load(const char* data, size_t size)
   
   // initialize stuff
   png_ptr =
-    PNG_PREFIX(png_create_read_struct(PNG_LIBPNG_VER_STRING, NULL, NULL, NULL));
+    png_create_read_struct(PNG_LIBPNG_VER_STRING, NULL, NULL, NULL);
   
   if(!png_ptr) {
     ERR(image, "[read_png_file] png_create_read_struct failed");
@@ -134,18 +131,18 @@ void GUI::Image::load(const char* data, size_t size)
     return;
   }
   
-  info_ptr = PNG_PREFIX(png_create_info_struct(png_ptr));
+  info_ptr = png_create_info_struct(png_ptr);
   if(!info_ptr) {
     ERR(image, "[read_png_file] png_create_info_struct failed");
     setError(2);
-    PNG_PREFIX(png_destroy_read_struct(&png_ptr, NULL, NULL));
+    png_destroy_read_struct(&png_ptr, NULL, NULL);
     return;
   }
   
-  if(setjmp(PNG_PREFIX(png_jmpbuf(png_ptr)))) {
+  if(setjmp(png_jmpbuf(png_ptr))) {
     ERR(image, "[read_png_file] Error during init_io");
     setError(3);
-    PNG_PREFIX(png_destroy_read_struct(&png_ptr, &info_ptr, NULL));
+    png_destroy_read_struct(&png_ptr, &info_ptr, NULL);
     return;
   }
   
@@ -154,37 +151,37 @@ void GUI::Image::load(const char* data, size_t size)
   dio.data = data;
   dio.size = size;
   dio.p = 8; // skip header
-  PNG_PREFIX(png_set_read_fn(png_ptr, &dio, dio_reader));
+  png_set_read_fn(png_ptr, &dio, dio_reader);
 
-  PNG_PREFIX(png_set_sig_bytes(png_ptr, 8));
+  png_set_sig_bytes(png_ptr, 8);
   
-  PNG_PREFIX(png_read_info(png_ptr, info_ptr));
+  png_read_info(png_ptr, info_ptr);
   
-  w = PNG_PREFIX(png_get_image_width(png_ptr, info_ptr));
-  h = PNG_PREFIX(png_get_image_height(png_ptr, info_ptr));
+  w = png_get_image_width(png_ptr, info_ptr);
+  h = png_get_image_height(png_ptr, info_ptr);
   //color_type = png_get_color_type(png_ptr, info_ptr);
   //bit_depth = png_get_bit_depth(png_ptr, info_ptr);
   
-  number_of_passes = PNG_PREFIX(png_set_interlace_handling(png_ptr));
-  PNG_PREFIX(png_read_update_info(png_ptr, info_ptr));
+  number_of_passes = png_set_interlace_handling(png_ptr);
+  png_read_update_info(png_ptr, info_ptr);
   
   // read file
-  if(setjmp(PNG_PREFIX(png_jmpbuf(png_ptr)))) {
+  if(setjmp(png_jmpbuf(png_ptr))) {
     ERR(image, "[read_png_file] Error during read_image");
     setError(4);
-    PNG_PREFIX(png_destroy_read_struct(&png_ptr, &info_ptr, NULL));
+    png_destroy_read_struct(&png_ptr, &info_ptr, NULL);
     return;
   }
   
   row_pointers = (png_bytep*) malloc(sizeof(png_bytep) * h);
   for(size_t y = 0; y < h; y++) {
     row_pointers[y] =
-      (png_byte*) malloc(PNG_PREFIX(png_get_rowbytes(png_ptr, info_ptr)));
+      (png_byte*) malloc(png_get_rowbytes(png_ptr, info_ptr));
   }
   
-  PNG_PREFIX(png_read_image(png_ptr, row_pointers));
+  png_read_image(png_ptr, row_pointers);
 
-  PNG_PREFIX(png_destroy_read_struct(&png_ptr, &info_ptr, NULL));
+  png_destroy_read_struct(&png_ptr, &info_ptr, NULL);
 }
 
 size_t GUI::Image::width()
diff --git a/plugingui/image.h b/plugingui/image.h
index 4f41a88..acfe964 100644
--- a/plugingui/image.h
+++ b/plugingui/image.h
@@ -27,7 +27,7 @@
 #ifndef __DRUMGIZMO_IMAGE_H__
 #define __DRUMGIZMO_IMAGE_H__
 
-#include "png/png.h"
+#include <png.h>
 #include <string>
 
 #include "colour.h"
diff --git a/plugingui/png/LICENSE b/plugingui/png/LICENSE
deleted file mode 100644
index 16a7d9e..0000000
--- a/plugingui/png/LICENSE
+++ /dev/null
@@ -1,111 +0,0 @@
-
-This copy of the libpng notices is provided for your convenience.  In case of
-any discrepancy between this copy and the notices in the file png.h that is
-included in the libpng distribution, the latter shall prevail.
-
-COPYRIGHT NOTICE, DISCLAIMER, and LICENSE:
-
-If you modify libpng you may insert additional notices immediately following
-this sentence.
-
-This code is released under the libpng license.
-
-libpng versions 1.2.6, August 15, 2004, through 1.5.13, September 27, 2012, are
-Copyright (c) 2004, 2006-2012 Glenn Randers-Pehrson, and are
-distributed according to the same disclaimer and license as libpng-1.2.5
-with the following individual added to the list of Contributing Authors
-
-   Cosmin Truta
-
-libpng versions 1.0.7, July 1, 2000, through 1.2.5 - October 3, 2002, are
-Copyright (c) 2000-2002 Glenn Randers-Pehrson, and are
-distributed according to the same disclaimer and license as libpng-1.0.6
-with the following individuals added to the list of Contributing Authors
-
-   Simon-Pierre Cadieux
-   Eric S. Raymond
-   Gilles Vollant
-
-and with the following additions to the disclaimer:
-
-   There is no warranty against interference with your enjoyment of the
-   library or against infringement.  There is no warranty that our
-   efforts or the library will fulfill any of your particular purposes
-   or needs.  This library is provided with all faults, and the entire
-   risk of satisfactory quality, performance, accuracy, and effort is with
-   the user.
-
-libpng versions 0.97, January 1998, through 1.0.6, March 20, 2000, are
-Copyright (c) 1998, 1999 Glenn Randers-Pehrson, and are
-distributed according to the same disclaimer and license as libpng-0.96,
-with the following individuals added to the list of Contributing Authors:
-
-   Tom Lane
-   Glenn Randers-Pehrson
-   Willem van Schaik
-
-libpng versions 0.89, June 1996, through 0.96, May 1997, are
-Copyright (c) 1996, 1997 Andreas Dilger
-Distributed according to the same disclaimer and license as libpng-0.88,
-with the following individuals added to the list of Contributing Authors:
-
-   John Bowler
-   Kevin Bracey
-   Sam Bushell
-   Magnus Holmgren
-   Greg Roelofs
-   Tom Tanner
-
-libpng versions 0.5, May 1995, through 0.88, January 1996, are
-Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.
-
-For the purposes of this copyright and license, "Contributing Authors"
-is defined as the following set of individuals:
-
-   Andreas Dilger
-   Dave Martindale
-   Guy Eric Schalnat
-   Paul Schmidt
-   Tim Wegner
-
-The PNG Reference Library is supplied "AS IS".  The Contributing Authors
-and Group 42, Inc. disclaim all warranties, expressed or implied,
-including, without limitation, the warranties of merchantability and of
-fitness for any purpose.  The Contributing Authors and Group 42, Inc.
-assume no liability for direct, indirect, incidental, special, exemplary,
-or consequential damages, which may result from the use of the PNG
-Reference Library, even if advised of the possibility of such damage.
-
-Permission is hereby granted to use, copy, modify, and distribute this
-source code, or portions hereof, for any purpose, without fee, subject
-to the following restrictions:
-
-1. The origin of this source code must not be misrepresented.
-
-2. Altered versions must be plainly marked as such and must not
-   be misrepresented as being the original source.
-
-3. This Copyright notice may not be removed or altered from any
-   source or altered source distribution.
-
-The Contributing Authors and Group 42, Inc. specifically permit, without
-fee, and encourage the use of this source code as a component to
-supporting the PNG file format in commercial products.  If you use this
-source code in a product, acknowledgment is not required but would be
-appreciated.
-
-
-A "png_get_copyright" function is available, for convenient use in "about"
-boxes and the like:
-
-   printf("%s",png_get_copyright(NULL));
-
-Also, the PNG logo (in PNG format, of course) is supplied in the
-files "pngbar.png" and "pngbar.jpg (88x31) and "pngnow.png" (98x31).
-
-Libpng is OSI Certified Open Source Software.  OSI Certified Open Source is a
-certification mark of the Open Source Initiative.
-
-Glenn Randers-Pehrson
-glennrp at users.sourceforge.net
-September 27, 2012
diff --git a/plugingui/png/README b/plugingui/png/README
deleted file mode 100644
index ca26e4b..0000000
--- a/plugingui/png/README
+++ /dev/null
@@ -1,202 +0,0 @@
-README for libpng version 1.5.13 - September 27, 2012 (shared library 15.0)
-See the note about version numbers near the top of png.h
-
-See INSTALL for instructions on how to install libpng.
-
-Libpng comes in several distribution formats.  Get libpng-*.tar.gz,
-libpng-*.tar.xz or libpng-*.tar.bz2 if you want UNIX-style line endings
-in the text files, or lpng*.zip if you want DOS-style line endings.
-
-Version 0.89 was the first official release of libpng.  Don't let the
-fact that it's the first release fool you.  The libpng library has been in
-extensive use and testing since mid-1995.  By late 1997 it had
-finally gotten to the stage where there hadn't been significant
-changes to the API in some time, and people have a bad feeling about
-libraries with versions < 1.0.  Version 1.0.0 was released in
-March 1998.
-
-****
-Note that some of the changes to the png_info structure render this
-version of the library binary incompatible with libpng-0.89 or
-earlier versions if you are using a shared library.  The type of the
-"filler" parameter for png_set_filler() has changed from png_byte to
-png_uint_32, which will affect shared-library applications that use
-this function.
-
-To avoid problems with changes to the internals of png_info_struct,
-new APIs have been made available in 0.95 to avoid direct application
-access to info_ptr.  These functions are the png_set_<chunk> and
-png_get_<chunk> functions.  These functions should be used when
-accessing/storing the info_struct data, rather than manipulating it
-directly, to avoid such problems in the future.
-
-It is important to note that the APIs do not make current programs
-that access the info struct directly incompatible with the new
-library.  However, it is strongly suggested that new programs use
-the new APIs (as shown in example.c and pngtest.c), and older programs
-be converted to the new format, to facilitate upgrades in the future.
-****
-
-Additions since 0.90 include the ability to compile libpng as a
-Windows DLL, and new APIs for accessing data in the info struct.
-Experimental functions include the ability to set weighting and cost
-factors for row filter selection, direct reads of integers from buffers
-on big-endian processors that support misaligned data access, faster
-methods of doing alpha composition, and more accurate 16->8 bit color
-conversion.
-
-The additions since 0.89 include the ability to read from a PNG stream
-which has had some (or all) of the signature bytes read by the calling
-application.  This also allows the reading of embedded PNG streams that
-do not have the PNG file signature.  As well, it is now possible to set
-the library action on the detection of chunk CRC errors.  It is possible
-to set different actions based on whether the CRC error occurred in a
-critical or an ancillary chunk.
-
-The changes made to the library, and bugs fixed are based on discussions
-on the PNG-implement mailing list and not on material submitted
-privately to Guy, Andreas, or Glenn.  They will forward any good
-suggestions to the list.
-
-For a detailed description on using libpng, read libpng-manual.txt.  For
-examples of libpng in a program, see example.c and pngtest.c.  For usage
-information and restrictions (what little they are) on libpng, see
-png.h.  For a description on using zlib (the compression library used by
-libpng) and zlib's restrictions, see zlib.h
-
-I have included a general makefile, as well as several machine and
-compiler specific ones, but you may have to modify one for your own needs.
-
-You should use zlib 1.0.4 or later to run this, but it MAY work with
-versions as old as zlib 0.95.  Even so, there are bugs in older zlib
-versions which can cause the output of invalid compression streams for
-some images.  You will definitely need zlib 1.0.4 or later if you are
-taking advantage of the MS-DOS "far" structure allocation for the small
-and medium memory models.  You should also note that zlib is a
-compression library that is useful for more things than just PNG files.
-You can use zlib as a drop-in replacement for fread() and fwrite() if
-you are so inclined.
-
-zlib should be available at the same place that libpng is, or at.
-ftp://ftp.info-zip.org/pub/infozip/zlib
-
-You may also want a copy of the PNG specification.  It is available
-as an RFC, a W3C Recommendation, and an ISO/IEC Standard.  You can find
-these at http://www.libpng.org/pub/png/documents/
-
-This code is currently being archived at libpng.sf.net in the
-[DOWNLOAD] area, and on CompuServe, Lib 20 (PNG SUPPORT)
-at GO GRAPHSUP.  If you can't find it in any of those places,
-e-mail me, and I'll help you find it.
-
-If you have any code changes, requests, problems, etc., please e-mail
-them to me.  Also, I'd appreciate any make files or project files,
-and any modifications you needed to make to get libpng to compile,
-along with a #define variable to tell what compiler/system you are on.
-If you needed to add transformations to libpng, or wish libpng would
-provide the image in a different way, drop me a note (and code, if
-possible), so I can consider supporting the transformation.
-Finally, if you get any warning messages when compiling libpng
-(note: not zlib), and they are easy to fix, I'd appreciate the
-fix.  Please mention "libpng" somewhere in the subject line.  Thanks.
-
-This release was created and will be supported by myself (of course
-based in a large way on Guy's and Andreas' earlier work), and the PNG
-development group.
-
-Send comments/corrections/commendations to png-mng-implement at
-lists.sourceforge.net (subscription required; visit 
-https://lists.sourceforge.net/lists/listinfo/png-mng-implement
-to subscribe) or to glennrp at users.sourceforge.net
-
-You can't reach Guy, the original libpng author, at the addresses
-given in previous versions of this document.  He and Andreas will
-read mail addressed to the png-implement list, however.
-
-Please do not send general questions about PNG.  Send them to
-png-mng-misc at lists.sf.net (subscription required; visit
-https://lists.sourceforge.net/lists/listinfo/png-mng-misc to
-subscribe).  If you have a question about something
-in the PNG specification that is related to using libpng, send it
-to me.  Send me any questions that start with "I was using libpng,
-and ...".  If in doubt, send questions to me.  I'll bounce them
-to others, if necessary.
-
-Please do not send suggestions on how to change PNG.  We have
-been discussing PNG for sixteen years now, and it is official and
-finished.  If you have suggestions for libpng, however, I'll
-gladly listen.  Even if your suggestion is not used immediately,
-it may be used later.
-
-Files in this distribution:
-
-      ANNOUNCE      =>  Announcement of this version, with recent changes
-      CHANGES       =>  Description of changes between libpng versions
-      KNOWNBUG      =>  List of known bugs and deficiencies
-      LICENSE       =>  License to use and redistribute libpng
-      README        =>  This file
-      TODO          =>  Things not implemented in the current library
-      Y2KINFO       =>  Statement of Y2K compliance
-      example.c     =>  Example code for using libpng functions
-      libpng.3      =>  manual page for libpng (includes libpng-manual.txt)
-      libpng-manual.txt  =>  Description of libpng and its functions
-      libpngpf.3    =>  manual page for libpng's private functions
-      png.5         =>  manual page for the PNG format
-      png.c         =>  Basic interface functions common to library
-      png.h         =>  Library function and interface declarations (public)
-      pngpriv.h     =>  Library function and interface declarations (private)
-      pngconf.h     =>  System specific library configuration (public)
-      pngstruct.h   =>  png_struct declaration (private)
-      pnginfo.h     =>  png_info struct declaration (private)
-      pngdebug.h    =>  debugging macros (private)
-      pngerror.c    =>  Error/warning message I/O functions
-      pngget.c      =>  Functions for retrieving info from struct
-      pngmem.c      =>  Memory handling functions
-      pngbar.png    =>  PNG logo, 88x31
-      pngnow.png    =>  PNG logo, 98x31
-      pngpread.c    =>  Progressive reading functions
-      pngread.c     =>  Read data/helper high-level functions
-      pngrio.c      =>  Lowest-level data read I/O functions
-      pngrtran.c    =>  Read data transformation functions
-      pngrutil.c    =>  Read data utility functions
-      pngset.c      =>  Functions for storing data into the info_struct
-      pngtest.c     =>  Library test program
-      pngtest.png   =>  Library test sample image
-      pngtrans.c    =>  Common data transformation functions
-      pngwio.c      =>  Lowest-level write I/O functions
-      pngwrite.c    =>  High-level write functions
-      pngwtran.c    =>  Write data transformations
-      pngwutil.c    =>  Write utility functions
-      contrib       =>  Contributions
-       gregbook         =>  source code for PNG reading and writing, from
-                            Greg Roelofs' "PNG: The Definitive Guide",
-                            O'Reilly, 1999
-       msvctest     =>  Builds and runs pngtest using a MSVC workspace
-       pngminus     =>  Simple pnm2png and png2pnm programs
-       pngsuite     =>  Test images
-       visupng      =>  Contains a MSVC workspace for VisualPng
-      projects      =>  Contains project files and workspaces for
-                        building a DLL
-       cbuilder5        =>  Contains a Borland workspace for building
-                            libpng and zlib
-       visualc6         =>  Contains a Microsoft Visual C++ (MSVC)
-                            workspace for building libpng and zlib
-       visualc71        =>  Contains a Microsoft Visual C++ (MSVC)
-                            workspace for building libpng and zlib
-       xcode            =>  Contains an Apple xcode
-                            workspace for building libpng and zlib
-      scripts       =>  Directory containing scripts for building libpng:
-                            (see scripts/README.txt for the list of scripts)
-
-Good luck, and happy coding.
-
--Glenn Randers-Pehrson (current maintainer, since 1998)
- Internet: glennrp at users.sourceforge.net
-
--Andreas Eric Dilger (former maintainer, 1996-1997)
- Internet: adilger at enel.ucalgary.ca
- Web: http://www-mddsp.enel.ucalgary.ca/People/adilger/
-
--Guy Eric Schalnat (original author and former maintainer, 1995-1996)
- (formerly of Group 42, Inc)
- Internet: gschal at infinet.com
diff --git a/plugingui/png/README.drumgizmo b/plugingui/png/README.drumgizmo
deleted file mode 100644
index e22e033..0000000
--- a/plugingui/png/README.drumgizmo
+++ /dev/null
@@ -1,6 +0,0 @@
-This folder contains a selection of files from the libpng project.
-They are included directly in the source tree in order to avoid version
-conflicts at loadtime when the plugin host is using a bundled version of
-libpng with a different version than the one shipped with the OS.
-
-See README and LICENSE files for more details on the libpng project.
\ No newline at end of file
diff --git a/plugingui/png/png.c b/plugingui/png/png.c
deleted file mode 100644
index 02c3044..0000000
--- a/plugingui/png/png.c
+++ /dev/null
@@ -1,2874 +0,0 @@
-
-/* png.c - location for general purpose libpng functions
- *
- * Last changed in libpng 1.5.11 [June 14, 2012]
- * Copyright (c) 1998-2012 Glenn Randers-Pehrson
- * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
- * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)
- *
- * This code is released under the libpng license.
- * For conditions of distribution and use, see the disclaimer
- * and license in png.h
- */
-
-#include "pngpriv.h"
-
-/* Generate a compiler error if there is an old png.h in the search path. */
-typedef png_libpng_version_1_5_13 Your_png_h_is_not_version_1_5_13;
-
-/* Tells libpng that we have already handled the first "num_bytes" bytes
- * of the PNG file signature.  If the PNG data is embedded into another
- * stream we can set num_bytes = 8 so that libpng will not attempt to read
- * or write any of the magic bytes before it starts on the IHDR.
- */
-
-#ifdef PNG_READ_SUPPORTED
-void PNGAPI
-dg_png_set_sig_bytes(png_structp png_ptr, int num_bytes)
-{
-   png_debug(1, "in png_set_sig_bytes");
-
-   if (png_ptr == NULL)
-      return;
-
-   if (num_bytes > 8)
-      dg_png_error(png_ptr, "Too many bytes for PNG signature");
-
-   png_ptr->sig_bytes = (png_byte)(num_bytes < 0 ? 0 : num_bytes);
-}
-
-/* Checks whether the supplied bytes match the PNG signature.  We allow
- * checking less than the full 8-byte signature so that those apps that
- * already read the first few bytes of a file to determine the file type
- * can simply check the remaining bytes for extra assurance.  Returns
- * an integer less than, equal to, or greater than zero if sig is found,
- * respectively, to be less than, to match, or be greater than the correct
- * PNG signature (this is the same behavior as strcmp, memcmp, etc).
- */
-int PNGAPI
-dg_png_sig_cmp(png_const_bytep sig, png_size_t start, png_size_t num_to_check)
-{
-   png_byte png_signature[8] = {137, 80, 78, 71, 13, 10, 26, 10};
-
-   if (num_to_check > 8)
-      num_to_check = 8;
-
-   else if (num_to_check < 1)
-      return (-1);
-
-   if (start > 7)
-      return (-1);
-
-   if (start + num_to_check > 8)
-      num_to_check = 8 - start;
-
-   return ((int)(png_memcmp(&sig[start], &png_signature[start], num_to_check)));
-}
-
-#endif /* PNG_READ_SUPPORTED */
-
-#if defined(PNG_READ_SUPPORTED) || defined(PNG_WRITE_SUPPORTED)
-/* Function to allocate memory for zlib */
-PNG_FUNCTION(voidpf /* PRIVATE */,
-png_zalloc,(voidpf png_ptr, uInt items, uInt size),PNG_ALLOCATED)
-{
-   png_voidp ptr;
-   png_structp p=(png_structp)png_ptr;
-   png_uint_32 save_flags=p->flags;
-   png_alloc_size_t num_bytes;
-
-   if (png_ptr == NULL)
-      return (NULL);
-
-   if (items > PNG_UINT_32_MAX/size)
-   {
-     png_warning (p, "Potential overflow in png_zalloc()");
-     return (NULL);
-   }
-   num_bytes = (png_alloc_size_t)items * size;
-
-   p->flags|=PNG_FLAG_MALLOC_NULL_MEM_OK;
-   ptr = (png_voidp)png_malloc((png_structp)png_ptr, num_bytes);
-   p->flags=save_flags;
-
-   return ((voidpf)ptr);
-}
-
-/* Function to free memory for zlib */
-void /* PRIVATE */
-png_zfree(voidpf png_ptr, voidpf ptr)
-{
-   png_free((png_structp)png_ptr, (png_voidp)ptr);
-}
-
-/* Reset the CRC variable to 32 bits of 1's.  Care must be taken
- * in case CRC is > 32 bits to leave the top bits 0.
- */
-void /* PRIVATE */
-png_reset_crc(png_structp png_ptr)
-{
-   /* The cast is safe because the crc is a 32 bit value. */
-   png_ptr->crc = (png_uint_32)crc32(0, Z_NULL, 0);
-}
-
-/* Calculate the CRC over a section of data.  We can only pass as
- * much data to this routine as the largest single buffer size.  We
- * also check that this data will actually be used before going to the
- * trouble of calculating it.
- */
-void /* PRIVATE */
-png_calculate_crc(png_structp png_ptr, png_const_bytep ptr, png_size_t length)
-{
-   int need_crc = 1;
-
-   if (PNG_CHUNK_ANCILLIARY(png_ptr->chunk_name))
-   {
-      if ((png_ptr->flags & PNG_FLAG_CRC_ANCILLARY_MASK) ==
-          (PNG_FLAG_CRC_ANCILLARY_USE | PNG_FLAG_CRC_ANCILLARY_NOWARN))
-         need_crc = 0;
-   }
-
-   else /* critical */
-   {
-      if (png_ptr->flags & PNG_FLAG_CRC_CRITICAL_IGNORE)
-         need_crc = 0;
-   }
-
-   /* 'uLong' is defined as unsigned long, this means that on some systems it is
-    * a 64 bit value.  crc32, however, returns 32 bits so the following cast is
-    * safe.  'uInt' may be no more than 16 bits, so it is necessary to perform a
-    * loop here.
-    */
-   if (need_crc && length > 0)
-   {
-      uLong crc = png_ptr->crc; /* Should never issue a warning */
-
-      do
-      {
-         uInt safeLength = (uInt)length;
-         if (safeLength == 0)
-            safeLength = (uInt)-1; /* evil, but safe */
-
-         crc = crc32(crc, ptr, safeLength);
-
-         /* The following should never issue compiler warnings, if they do the
-          * target system has characteristics that will probably violate other
-          * assumptions within the libpng code.
-          */
-         ptr += safeLength;
-         length -= safeLength;
-      }
-      while (length > 0);
-
-      /* And the following is always safe because the crc is only 32 bits. */
-      png_ptr->crc = (png_uint_32)crc;
-   }
-}
-
-/* Check a user supplied version number, called from both read and write
- * functions that create a png_struct
- */
-int
-png_user_version_check(png_structp png_ptr, png_const_charp user_png_ver)
-{
-   if (user_png_ver)
-   {
-      int i = 0;
-
-      do
-      {
-         if (user_png_ver[i] != png_libpng_ver[i])
-            png_ptr->flags |= PNG_FLAG_LIBRARY_MISMATCH;
-      } while (png_libpng_ver[i++]);
-   }
-
-   else
-      png_ptr->flags |= PNG_FLAG_LIBRARY_MISMATCH;
-
-   if (png_ptr->flags & PNG_FLAG_LIBRARY_MISMATCH)
-   {
-     /* Libpng 0.90 and later are binary incompatible with libpng 0.89, so
-      * we must recompile any applications that use any older library version.
-      * For versions after libpng 1.0, we will be compatible, so we need
-      * only check the first digit.
-      */
-      if (user_png_ver == NULL || user_png_ver[0] != png_libpng_ver[0] ||
-          (user_png_ver[0] == '1' && user_png_ver[2] != png_libpng_ver[2]) ||
-          (user_png_ver[0] == '0' && user_png_ver[2] < '9'))
-      {
-#ifdef PNG_WARNINGS_SUPPORTED
-         size_t pos = 0;
-         char m[128];
-
-         pos = png_safecat(m, sizeof m, pos, "Application built with libpng-");
-         pos = png_safecat(m, sizeof m, pos, user_png_ver);
-         pos = png_safecat(m, sizeof m, pos, " but running with ");
-         pos = png_safecat(m, sizeof m, pos, png_libpng_ver);
-
-         png_warning(png_ptr, m);
-#endif
-
-#ifdef PNG_ERROR_NUMBERS_SUPPORTED
-         png_ptr->flags = 0;
-#endif
-
-         return 0;
-      }
-   }
-
-   /* Success return. */
-   return 1;
-}
-
-/* Allocate the memory for an info_struct for the application.  We don't
- * really need the png_ptr, but it could potentially be useful in the
- * future.  This should be used in favour of malloc(png_sizeof(png_info))
- * and png_info_init() so that applications that want to use a shared
- * libpng don't have to be recompiled if png_info changes size.
- */
-PNG_FUNCTION(png_infop,PNGAPI
-dg_png_create_info_struct,(png_structp png_ptr),PNG_ALLOCATED)
-{
-   png_infop info_ptr;
-
-   png_debug(1, "in png_create_info_struct");
-
-   if (png_ptr == NULL)
-      return (NULL);
-
-#ifdef PNG_USER_MEM_SUPPORTED
-   info_ptr = (png_infop)png_create_struct_2(PNG_STRUCT_INFO,
-      png_ptr->malloc_fn, png_ptr->mem_ptr);
-#else
-   info_ptr = (png_infop)png_create_struct(PNG_STRUCT_INFO);
-#endif
-   if (info_ptr != NULL)
-      png_info_init_3(&info_ptr, png_sizeof(png_info));
-
-   return (info_ptr);
-}
-
-/* This function frees the memory associated with a single info struct.
- * Normally, one would use either png_destroy_read_struct() or
- * png_destroy_write_struct() to free an info struct, but this may be
- * useful for some applications.
- */
-void PNGAPI
-png_destroy_info_struct(png_structp png_ptr, png_infopp info_ptr_ptr)
-{
-   png_infop info_ptr = NULL;
-
-   png_debug(1, "in png_destroy_info_struct");
-
-   if (png_ptr == NULL)
-      return;
-
-   if (info_ptr_ptr != NULL)
-      info_ptr = *info_ptr_ptr;
-
-   if (info_ptr != NULL)
-   {
-      png_info_destroy(png_ptr, info_ptr);
-
-#ifdef PNG_USER_MEM_SUPPORTED
-      png_destroy_struct_2((png_voidp)info_ptr, png_ptr->free_fn,
-          png_ptr->mem_ptr);
-#else
-      png_destroy_struct((png_voidp)info_ptr);
-#endif
-      *info_ptr_ptr = NULL;
-   }
-}
-
-/* Initialize the info structure.  This is now an internal function (0.89)
- * and applications using it are urged to use png_create_info_struct()
- * instead.
- */
-
-void PNGAPI
-png_info_init_3(png_infopp ptr_ptr, png_size_t png_info_struct_size)
-{
-   png_infop info_ptr = *ptr_ptr;
-
-   png_debug(1, "in png_info_init_3");
-
-   if (info_ptr == NULL)
-      return;
-
-   if (png_sizeof(png_info) > png_info_struct_size)
-   {
-      png_destroy_struct(info_ptr);
-      info_ptr = (png_infop)png_create_struct(PNG_STRUCT_INFO);
-      *ptr_ptr = info_ptr;
-   }
-
-   /* Set everything to 0 */
-   png_memset(info_ptr, 0, png_sizeof(png_info));
-}
-
-void PNGAPI
-png_data_freer(png_structp png_ptr, png_infop info_ptr,
-   int freer, png_uint_32 mask)
-{
-   png_debug(1, "in png_data_freer");
-
-   if (png_ptr == NULL || info_ptr == NULL)
-      return;
-
-   if (freer == PNG_DESTROY_WILL_FREE_DATA)
-      info_ptr->free_me |= mask;
-
-   else if (freer == PNG_USER_WILL_FREE_DATA)
-      info_ptr->free_me &= ~mask;
-
-   else
-      png_warning(png_ptr,
-         "Unknown freer parameter in png_data_freer");
-}
-
-void PNGAPI
-png_free_data(png_structp png_ptr, png_infop info_ptr, png_uint_32 mask,
-   int num)
-{
-   png_debug(1, "in png_free_data");
-
-   if (png_ptr == NULL || info_ptr == NULL)
-      return;
-
-#ifdef PNG_TEXT_SUPPORTED
-   /* Free text item num or (if num == -1) all text items */
-   if ((mask & PNG_FREE_TEXT) & info_ptr->free_me)
-   {
-      if (num != -1)
-      {
-         if (info_ptr->text && info_ptr->text[num].key)
-         {
-            png_free(png_ptr, info_ptr->text[num].key);
-            info_ptr->text[num].key = NULL;
-         }
-      }
-
-      else
-      {
-         int i;
-         for (i = 0; i < info_ptr->num_text; i++)
-             png_free_data(png_ptr, info_ptr, PNG_FREE_TEXT, i);
-         png_free(png_ptr, info_ptr->text);
-         info_ptr->text = NULL;
-         info_ptr->num_text=0;
-      }
-   }
-#endif
-
-#ifdef PNG_tRNS_SUPPORTED
-   /* Free any tRNS entry */
-   if ((mask & PNG_FREE_TRNS) & info_ptr->free_me)
-   {
-      png_free(png_ptr, info_ptr->trans_alpha);
-      info_ptr->trans_alpha = NULL;
-      info_ptr->valid &= ~PNG_INFO_tRNS;
-   }
-#endif
-
-#ifdef PNG_sCAL_SUPPORTED
-   /* Free any sCAL entry */
-   if ((mask & PNG_FREE_SCAL) & info_ptr->free_me)
-   {
-      png_free(png_ptr, info_ptr->scal_s_width);
-      png_free(png_ptr, info_ptr->scal_s_height);
-      info_ptr->scal_s_width = NULL;
-      info_ptr->scal_s_height = NULL;
-      info_ptr->valid &= ~PNG_INFO_sCAL;
-   }
-#endif
-
-#ifdef PNG_pCAL_SUPPORTED
-   /* Free any pCAL entry */
-   if ((mask & PNG_FREE_PCAL) & info_ptr->free_me)
-   {
-      png_free(png_ptr, info_ptr->pcal_purpose);
-      png_free(png_ptr, info_ptr->pcal_units);
-      info_ptr->pcal_purpose = NULL;
-      info_ptr->pcal_units = NULL;
-      if (info_ptr->pcal_params != NULL)
-         {
-            int i;
-            for (i = 0; i < (int)info_ptr->pcal_nparams; i++)
-            {
-               png_free(png_ptr, info_ptr->pcal_params[i]);
-               info_ptr->pcal_params[i] = NULL;
-            }
-            png_free(png_ptr, info_ptr->pcal_params);
-            info_ptr->pcal_params = NULL;
-         }
-      info_ptr->valid &= ~PNG_INFO_pCAL;
-   }
-#endif
-
-#ifdef PNG_iCCP_SUPPORTED
-   /* Free any iCCP entry */
-   if ((mask & PNG_FREE_ICCP) & info_ptr->free_me)
-   {
-      png_free(png_ptr, info_ptr->iccp_name);
-      png_free(png_ptr, info_ptr->iccp_profile);
-      info_ptr->iccp_name = NULL;
-      info_ptr->iccp_profile = NULL;
-      info_ptr->valid &= ~PNG_INFO_iCCP;
-   }
-#endif
-
-#ifdef PNG_sPLT_SUPPORTED
-   /* Free a given sPLT entry, or (if num == -1) all sPLT entries */
-   if ((mask & PNG_FREE_SPLT) & info_ptr->free_me)
-   {
-      if (num != -1)
-      {
-         if (info_ptr->splt_palettes)
-         {
-            png_free(png_ptr, info_ptr->splt_palettes[num].name);
-            png_free(png_ptr, info_ptr->splt_palettes[num].entries);
-            info_ptr->splt_palettes[num].name = NULL;
-            info_ptr->splt_palettes[num].entries = NULL;
-         }
-      }
-
-      else
-      {
-         if (info_ptr->splt_palettes_num)
-         {
-            int i;
-            for (i = 0; i < (int)info_ptr->splt_palettes_num; i++)
-               png_free_data(png_ptr, info_ptr, PNG_FREE_SPLT, i);
-
-            png_free(png_ptr, info_ptr->splt_palettes);
-            info_ptr->splt_palettes = NULL;
-            info_ptr->splt_palettes_num = 0;
-         }
-         info_ptr->valid &= ~PNG_INFO_sPLT;
-      }
-   }
-#endif
-
-#ifdef PNG_UNKNOWN_CHUNKS_SUPPORTED
-   if (png_ptr->unknown_chunk.data)
-   {
-      png_free(png_ptr, png_ptr->unknown_chunk.data);
-      png_ptr->unknown_chunk.data = NULL;
-   }
-
-   if ((mask & PNG_FREE_UNKN) & info_ptr->free_me)
-   {
-      if (num != -1)
-      {
-          if (info_ptr->unknown_chunks)
-          {
-             png_free(png_ptr, info_ptr->unknown_chunks[num].data);
-             info_ptr->unknown_chunks[num].data = NULL;
-          }
-      }
-
-      else
-      {
-         int i;
-
-         if (info_ptr->unknown_chunks_num)
-         {
-            for (i = 0; i < info_ptr->unknown_chunks_num; i++)
-               png_free_data(png_ptr, info_ptr, PNG_FREE_UNKN, i);
-
-            png_free(png_ptr, info_ptr->unknown_chunks);
-            info_ptr->unknown_chunks = NULL;
-            info_ptr->unknown_chunks_num = 0;
-         }
-      }
-   }
-#endif
-
-#ifdef PNG_hIST_SUPPORTED
-   /* Free any hIST entry */
-   if ((mask & PNG_FREE_HIST)  & info_ptr->free_me)
-   {
-      png_free(png_ptr, info_ptr->hist);
-      info_ptr->hist = NULL;
-      info_ptr->valid &= ~PNG_INFO_hIST;
-   }
-#endif
-
-   /* Free any PLTE entry that was internally allocated */
-   if ((mask & PNG_FREE_PLTE) & info_ptr->free_me)
-   {
-      png_zfree(png_ptr, info_ptr->palette);
-      info_ptr->palette = NULL;
-      info_ptr->valid &= ~PNG_INFO_PLTE;
-      info_ptr->num_palette = 0;
-   }
-
-#ifdef PNG_INFO_IMAGE_SUPPORTED
-   /* Free any image bits attached to the info structure */
-   if ((mask & PNG_FREE_ROWS) & info_ptr->free_me)
-   {
-      if (info_ptr->row_pointers)
-      {
-         int row;
-         for (row = 0; row < (int)info_ptr->height; row++)
-         {
-            png_free(png_ptr, info_ptr->row_pointers[row]);
-            info_ptr->row_pointers[row] = NULL;
-         }
-         png_free(png_ptr, info_ptr->row_pointers);
-         info_ptr->row_pointers = NULL;
-      }
-      info_ptr->valid &= ~PNG_INFO_IDAT;
-   }
-#endif
-
-   if (num != -1)
-      mask &= ~PNG_FREE_MUL;
-
-   info_ptr->free_me &= ~mask;
-}
-
-/* This is an internal routine to free any memory that the info struct is
- * pointing to before re-using it or freeing the struct itself.  Recall
- * that png_free() checks for NULL pointers for us.
- */
-void /* PRIVATE */
-png_info_destroy(png_structp png_ptr, png_infop info_ptr)
-{
-   png_debug(1, "in png_info_destroy");
-
-   png_free_data(png_ptr, info_ptr, PNG_FREE_ALL, -1);
-
-#ifdef PNG_HANDLE_AS_UNKNOWN_SUPPORTED
-   if (png_ptr->num_chunk_list)
-   {
-      png_free(png_ptr, png_ptr->chunk_list);
-      png_ptr->chunk_list = NULL;
-      png_ptr->num_chunk_list = 0;
-   }
-#endif
-
-   png_info_init_3(&info_ptr, png_sizeof(png_info));
-}
-#endif /* defined(PNG_READ_SUPPORTED) || defined(PNG_WRITE_SUPPORTED) */
-
-/* This function returns a pointer to the io_ptr associated with the user
- * functions.  The application should free any memory associated with this
- * pointer before png_write_destroy() or png_read_destroy() are called.
- */
-png_voidp PNGAPI
-dg_png_get_io_ptr(png_structp png_ptr)
-{
-   if (png_ptr == NULL)
-      return (NULL);
-
-   return (png_ptr->io_ptr);
-}
-
-#if defined(PNG_READ_SUPPORTED) || defined(PNG_WRITE_SUPPORTED)
-#  ifdef PNG_STDIO_SUPPORTED
-/* Initialize the default input/output functions for the PNG file.  If you
- * use your own read or write routines, you can call either png_set_read_fn()
- * or png_set_write_fn() instead of png_init_io().  If you have defined
- * PNG_NO_STDIO or otherwise disabled PNG_STDIO_SUPPORTED, you must use a
- * function of your own because "FILE *" isn't necessarily available.
- */
-void PNGAPI
-png_init_io(png_structp png_ptr, png_FILE_p fp)
-{
-   png_debug(1, "in png_init_io");
-
-   if (png_ptr == NULL)
-      return;
-
-   png_ptr->io_ptr = (png_voidp)fp;
-}
-#  endif
-
-#  ifdef PNG_TIME_RFC1123_SUPPORTED
-/* Convert the supplied time into an RFC 1123 string suitable for use in
- * a "Creation Time" or other text-based time string.
- */
-png_const_charp PNGAPI
-png_convert_to_rfc1123(png_structp png_ptr, png_const_timep ptime)
-{
-   static PNG_CONST char short_months[12][4] =
-        {"Jan", "Feb", "Mar", "Apr", "May", "Jun",
-         "Jul", "Aug", "Sep", "Oct", "Nov", "Dec"};
-
-   if (png_ptr == NULL)
-      return (NULL);
-
-   if (ptime->year > 9999 /* RFC1123 limitation */ ||
-       ptime->month == 0    ||  ptime->month > 12  ||
-       ptime->day   == 0    ||  ptime->day   > 31  ||
-       ptime->hour  > 23    ||  ptime->minute > 59 ||
-       ptime->second > 60)
-   {
-      png_warning(png_ptr, "Ignoring invalid time value");
-      return (NULL);
-   }
-
-   {
-      size_t pos = 0;
-      char number_buf[5]; /* enough for a four-digit year */
-
-#     define APPEND_STRING(string)\
-         pos = png_safecat(png_ptr->time_buffer, sizeof png_ptr->time_buffer,\
-            pos, (string))
-#     define APPEND_NUMBER(format, value)\
-         APPEND_STRING(PNG_FORMAT_NUMBER(number_buf, format, (value)))
-#     define APPEND(ch)\
-         if (pos < (sizeof png_ptr->time_buffer)-1)\
-            png_ptr->time_buffer[pos++] = (ch)
-
-      APPEND_NUMBER(PNG_NUMBER_FORMAT_u, (unsigned)ptime->day);
-      APPEND(' ');
-      APPEND_STRING(short_months[(ptime->month - 1)]);
-      APPEND(' ');
-      APPEND_NUMBER(PNG_NUMBER_FORMAT_u, ptime->year);
-      APPEND(' ');
-      APPEND_NUMBER(PNG_NUMBER_FORMAT_02u, (unsigned)ptime->hour);
-      APPEND(':');
-      APPEND_NUMBER(PNG_NUMBER_FORMAT_02u, (unsigned)ptime->minute);
-      APPEND(':');
-      APPEND_NUMBER(PNG_NUMBER_FORMAT_02u, (unsigned)ptime->second);
-      APPEND_STRING(" +0000"); /* This reliably terminates the buffer */
-
-#     undef APPEND
-#     undef APPEND_NUMBER
-#     undef APPEND_STRING
-   }
-
-   return png_ptr->time_buffer;
-}
-#  endif /* PNG_TIME_RFC1123_SUPPORTED */
-
-#endif /* defined(PNG_READ_SUPPORTED) || defined(PNG_WRITE_SUPPORTED) */
-
-png_const_charp PNGAPI
-png_get_copyright(png_const_structp png_ptr)
-{
-   PNG_UNUSED(png_ptr)  /* Silence compiler warning about unused png_ptr */
-#ifdef PNG_STRING_COPYRIGHT
-   return PNG_STRING_COPYRIGHT
-#else
-#  ifdef __STDC__
-   return PNG_STRING_NEWLINE \
-     "libpng version 1.5.13 - September 27, 2012" PNG_STRING_NEWLINE \
-     "Copyright (c) 1998-2012 Glenn Randers-Pehrson" PNG_STRING_NEWLINE \
-     "Copyright (c) 1996-1997 Andreas Dilger" PNG_STRING_NEWLINE \
-     "Copyright (c) 1995-1996 Guy Eric Schalnat, Group 42, Inc." \
-     PNG_STRING_NEWLINE;
-#  else
-      return "libpng version 1.5.13 - September 27, 2012\
-      Copyright (c) 1998-2012 Glenn Randers-Pehrson\
-      Copyright (c) 1996-1997 Andreas Dilger\
-      Copyright (c) 1995-1996 Guy Eric Schalnat, Group 42, Inc.";
-#  endif
-#endif
-}
-
-/* The following return the library version as a short string in the
- * format 1.0.0 through 99.99.99zz.  To get the version of *.h files
- * used with your application, print out PNG_LIBPNG_VER_STRING, which
- * is defined in png.h.
- * Note: now there is no difference between png_get_libpng_ver() and
- * png_get_header_ver().  Due to the version_nn_nn_nn typedef guard,
- * it is guaranteed that png.c uses the correct version of png.h.
- */
-png_const_charp PNGAPI
-png_get_libpng_ver(png_const_structp png_ptr)
-{
-   /* Version of *.c files used when building libpng */
-   return png_get_header_ver(png_ptr);
-}
-
-png_const_charp PNGAPI
-png_get_header_ver(png_const_structp png_ptr)
-{
-   /* Version of *.h files used when building libpng */
-   PNG_UNUSED(png_ptr)  /* Silence compiler warning about unused png_ptr */
-   return PNG_LIBPNG_VER_STRING;
-}
-
-png_const_charp PNGAPI
-png_get_header_version(png_const_structp png_ptr)
-{
-   /* Returns longer string containing both version and date */
-   PNG_UNUSED(png_ptr)  /* Silence compiler warning about unused png_ptr */
-#ifdef __STDC__
-   return PNG_HEADER_VERSION_STRING
-#  ifndef PNG_READ_SUPPORTED
-   "     (NO READ SUPPORT)"
-#  endif
-   PNG_STRING_NEWLINE;
-#else
-   return PNG_HEADER_VERSION_STRING;
-#endif
-}
-
-#ifdef PNG_HANDLE_AS_UNKNOWN_SUPPORTED
-int PNGAPI
-png_handle_as_unknown(png_structp png_ptr, png_const_bytep chunk_name)
-{
-   /* Check chunk_name and return "keep" value if it's on the list, else 0 */
-   png_const_bytep p, p_end;
-
-   if (png_ptr == NULL || chunk_name == NULL || png_ptr->num_chunk_list <= 0)
-      return PNG_HANDLE_CHUNK_AS_DEFAULT;
-
-   p_end = png_ptr->chunk_list;
-   p = p_end + png_ptr->num_chunk_list*5; /* beyond end */
-
-   /* The code is the fifth byte after each four byte string.  Historically this
-    * code was always searched from the end of the list, so it should continue
-    * to do so in case there are duplicated entries.
-    */
-   do /* num_chunk_list > 0, so at least one */
-   {
-      p -= 5;
-      if (!png_memcmp(chunk_name, p, 4))
-         return p[4];
-   }
-   while (p > p_end);
-
-   return PNG_HANDLE_CHUNK_AS_DEFAULT;
-}
-
-int /* PRIVATE */
-png_chunk_unknown_handling(png_structp png_ptr, png_uint_32 chunk_name)
-{
-   png_byte chunk_string[5];
-
-   PNG_CSTRING_FROM_CHUNK(chunk_string, chunk_name);
-   return png_handle_as_unknown(png_ptr, chunk_string);
-}
-#endif
-
-#ifdef PNG_READ_SUPPORTED
-/* This function, added to libpng-1.0.6g, is untested. */
-int PNGAPI
-png_reset_zstream(png_structp png_ptr)
-{
-   if (png_ptr == NULL)
-      return Z_STREAM_ERROR;
-
-   return (inflateReset(&png_ptr->zstream));
-}
-#endif /* PNG_READ_SUPPORTED */
-
-/* This function was added to libpng-1.0.7 */
-png_uint_32 PNGAPI
-png_access_version_number(void)
-{
-   /* Version of *.c files used when building libpng */
-   return((png_uint_32)PNG_LIBPNG_VER);
-}
-
-
-
-#if defined(PNG_READ_SUPPORTED) || defined(PNG_WRITE_SUPPORTED)
-/* png_convert_size: a PNGAPI but no longer in png.h, so deleted
- * at libpng 1.5.5!
- */
-
-/* Added at libpng version 1.2.34 and 1.4.0 (moved from pngset.c) */
-#  ifdef PNG_CHECK_cHRM_SUPPORTED
-
-int /* PRIVATE */
-png_check_cHRM_fixed(png_structp png_ptr,
-   png_fixed_point white_x, png_fixed_point white_y, png_fixed_point red_x,
-   png_fixed_point red_y, png_fixed_point green_x, png_fixed_point green_y,
-   png_fixed_point blue_x, png_fixed_point blue_y)
-{
-   int ret = 1;
-   unsigned long xy_hi,xy_lo,yx_hi,yx_lo;
-
-   png_debug(1, "in function png_check_cHRM_fixed");
-
-   if (png_ptr == NULL)
-      return 0;
-
-   /* (x,y,z) values are first limited to 0..100000 (PNG_FP_1), the white
-    * y must also be greater than 0.  To test for the upper limit calculate
-    * (PNG_FP_1-y) - x must be <= to this for z to be >= 0 (and the expression
-    * cannot overflow.)  At this point we know x and y are >= 0 and (x+y) is
-    * <= PNG_FP_1.  The previous test on PNG_MAX_UINT_31 is removed because it
-    * pointless (and it produces compiler warnings!)
-    */
-   if (white_x < 0 || white_y <= 0 ||
-         red_x < 0 ||   red_y <  0 ||
-       green_x < 0 || green_y <  0 ||
-        blue_x < 0 ||  blue_y <  0)
-   {
-      png_warning(png_ptr,
-        "Ignoring attempt to set negative chromaticity value");
-      ret = 0;
-   }
-   /* And (x+y) must be <= PNG_FP_1 (so z is >= 0) */
-   if (white_x > PNG_FP_1 - white_y)
-   {
-      png_warning(png_ptr, "Invalid cHRM white point");
-      ret = 0;
-   }
-
-   if (red_x > PNG_FP_1 - red_y)
-   {
-      png_warning(png_ptr, "Invalid cHRM red point");
-      ret = 0;
-   }
-
-   if (green_x > PNG_FP_1 - green_y)
-   {
-      png_warning(png_ptr, "Invalid cHRM green point");
-      ret = 0;
-   }
-
-   if (blue_x > PNG_FP_1 - blue_y)
-   {
-      png_warning(png_ptr, "Invalid cHRM blue point");
-      ret = 0;
-   }
-
-   png_64bit_product(green_x - red_x, blue_y - red_y, &xy_hi, &xy_lo);
-   png_64bit_product(green_y - red_y, blue_x - red_x, &yx_hi, &yx_lo);
-
-   if (xy_hi == yx_hi && xy_lo == yx_lo)
-   {
-      png_warning(png_ptr,
-         "Ignoring attempt to set cHRM RGB triangle with zero area");
-      ret = 0;
-   }
-
-   return ret;
-}
-#  endif /* PNG_CHECK_cHRM_SUPPORTED */
-
-#ifdef PNG_cHRM_SUPPORTED
-/* Added at libpng-1.5.5 to support read and write of true CIEXYZ values for
- * cHRM, as opposed to using chromaticities.  These internal APIs return
- * non-zero on a parameter error.  The X, Y and Z values are required to be
- * positive and less than 1.0.
- */
-int png_xy_from_XYZ(png_xy *xy, png_XYZ XYZ)
-{
-   png_int_32 d, dwhite, whiteX, whiteY;
-
-   d = XYZ.redX + XYZ.redY + XYZ.redZ;
-   if (!png_muldiv(&xy->redx, XYZ.redX, PNG_FP_1, d)) return 1;
-   if (!png_muldiv(&xy->redy, XYZ.redY, PNG_FP_1, d)) return 1;
-   dwhite = d;
-   whiteX = XYZ.redX;
-   whiteY = XYZ.redY;
-
-   d = XYZ.greenX + XYZ.greenY + XYZ.greenZ;
-   if (!png_muldiv(&xy->greenx, XYZ.greenX, PNG_FP_1, d)) return 1;
-   if (!png_muldiv(&xy->greeny, XYZ.greenY, PNG_FP_1, d)) return 1;
-   dwhite += d;
-   whiteX += XYZ.greenX;
-   whiteY += XYZ.greenY;
-
-   d = XYZ.blueX + XYZ.blueY + XYZ.blueZ;
-   if (!png_muldiv(&xy->bluex, XYZ.blueX, PNG_FP_1, d)) return 1;
-   if (!png_muldiv(&xy->bluey, XYZ.blueY, PNG_FP_1, d)) return 1;
-   dwhite += d;
-   whiteX += XYZ.blueX;
-   whiteY += XYZ.blueY;
-
-   /* The reference white is simply the same of the end-point (X,Y,Z) vectors,
-    * thus:
-    */
-   if (!png_muldiv(&xy->whitex, whiteX, PNG_FP_1, dwhite)) return 1;
-   if (!png_muldiv(&xy->whitey, whiteY, PNG_FP_1, dwhite)) return 1;
-
-   return 0;
-}
-
-int png_XYZ_from_xy(png_XYZ *XYZ, png_xy xy)
-{
-   png_fixed_point red_inverse, green_inverse, blue_scale;
-   png_fixed_point left, right, denominator;
-
-   /* Check xy and, implicitly, z.  Note that wide gamut color spaces typically
-    * have end points with 0 tristimulus values (these are impossible end
-    * points, but they are used to cover the possible colors.)
-    */
-   if (xy.redx < 0 || xy.redx > PNG_FP_1) return 1;
-   if (xy.redy < 0 || xy.redy > PNG_FP_1-xy.redx) return 1;
-   if (xy.greenx < 0 || xy.greenx > PNG_FP_1) return 1;
-   if (xy.greeny < 0 || xy.greeny > PNG_FP_1-xy.greenx) return 1;
-   if (xy.bluex < 0 || xy.bluex > PNG_FP_1) return 1;
-   if (xy.bluey < 0 || xy.bluey > PNG_FP_1-xy.bluex) return 1;
-   if (xy.whitex < 0 || xy.whitex > PNG_FP_1) return 1;
-   if (xy.whitey < 0 || xy.whitey > PNG_FP_1-xy.whitex) return 1;
-
-   /* The reverse calculation is more difficult because the original tristimulus
-    * value had 9 independent values (red,green,blue)x(X,Y,Z) however only 8
-    * derived values were recorded in the cHRM chunk;
-    * (red,green,blue,white)x(x,y).  This loses one degree of freedom and
-    * therefore an arbitrary ninth value has to be introduced to undo the
-    * original transformations.
-    *
-    * Think of the original end-points as points in (X,Y,Z) space.  The
-    * chromaticity values (c) have the property:
-    *
-    *           C
-    *   c = ---------
-    *       X + Y + Z
-    *
-    * For each c (x,y,z) from the corresponding original C (X,Y,Z).  Thus the
-    * three chromaticity values (x,y,z) for each end-point obey the
-    * relationship:
-    *
-    *   x + y + z = 1
-    *
-    * This describes the plane in (X,Y,Z) space that intersects each axis at the
-    * value 1.0; call this the chromaticity plane.  Thus the chromaticity
-    * calculation has scaled each end-point so that it is on the x+y+z=1 plane
-    * and chromaticity is the intersection of the vector from the origin to the
-    * (X,Y,Z) value with the chromaticity plane.
-    *
-    * To fully invert the chromaticity calculation we would need the three
-    * end-point scale factors, (red-scale, green-scale, blue-scale), but these
-    * were not recorded.  Instead we calculated the reference white (X,Y,Z) and
-    * recorded the chromaticity of this.  The reference white (X,Y,Z) would have
-    * given all three of the scale factors since:
-    *
-    *    color-C = color-c * color-scale
-    *    white-C = red-C + green-C + blue-C
-    *            = red-c*red-scale + green-c*green-scale + blue-c*blue-scale
-    *
-    * But cHRM records only white-x and white-y, so we have lost the white scale
-    * factor:
-    *
-    *    white-C = white-c*white-scale
-    *
-    * To handle this the inverse transformation makes an arbitrary assumption
-    * about white-scale:
-    *
-    *    Assume: white-Y = 1.0
-    *    Hence:  white-scale = 1/white-y
-    *    Or:     red-Y + green-Y + blue-Y = 1.0
-    *
-    * Notice the last statement of the assumption gives an equation in three of
-    * the nine values we want to calculate.  8 more equations come from the
-    * above routine as summarised at the top above (the chromaticity
-    * calculation):
-    *
-    *    Given: color-x = color-X / (color-X + color-Y + color-Z)
-    *    Hence: (color-x - 1)*color-X + color.x*color-Y + color.x*color-Z = 0
-    *
-    * This is 9 simultaneous equations in the 9 variables "color-C" and can be
-    * solved by Cramer's rule.  Cramer's rule requires calculating 10 9x9 matrix
-    * determinants, however this is not as bad as it seems because only 28 of
-    * the total of 90 terms in the various matrices are non-zero.  Nevertheless
-    * Cramer's rule is notoriously numerically unstable because the determinant
-    * calculation involves the difference of large, but similar, numbers.  It is
-    * difficult to be sure that the calculation is stable for real world values
-    * and it is certain that it becomes unstable where the end points are close
-    * together.
-    *
-    * So this code uses the perhaps slightly less optimal but more
-    * understandable and totally obvious approach of calculating color-scale.
-    *
-    * This algorithm depends on the precision in white-scale and that is
-    * (1/white-y), so we can immediately see that as white-y approaches 0 the
-    * accuracy inherent in the cHRM chunk drops off substantially.
-    *
-    * libpng arithmetic: a simple invertion of the above equations
-    * ------------------------------------------------------------
-    *
-    *    white_scale = 1/white-y
-    *    white-X = white-x * white-scale
-    *    white-Y = 1.0
-    *    white-Z = (1 - white-x - white-y) * white_scale
-    *
-    *    white-C = red-C + green-C + blue-C
-    *            = red-c*red-scale + green-c*green-scale + blue-c*blue-scale
-    *
-    * This gives us three equations in (red-scale,green-scale,blue-scale) where
-    * all the coefficients are now known:
-    *
-    *    red-x*red-scale + green-x*green-scale + blue-x*blue-scale
-    *       = white-x/white-y
-    *    red-y*red-scale + green-y*green-scale + blue-y*blue-scale = 1
-    *    red-z*red-scale + green-z*green-scale + blue-z*blue-scale
-    *       = (1 - white-x - white-y)/white-y
-    *
-    * In the last equation color-z is (1 - color-x - color-y) so we can add all
-    * three equations together to get an alternative third:
-    *
-    *    red-scale + green-scale + blue-scale = 1/white-y = white-scale
-    *
-    * So now we have a Cramer's rule solution where the determinants are just
-    * 3x3 - far more tractible.  Unfortunately 3x3 determinants still involve
-    * multiplication of three coefficients so we can't guarantee to avoid
-    * overflow in the libpng fixed point representation.  Using Cramer's rule in
-    * floating point is probably a good choice here, but it's not an option for
-    * fixed point.  Instead proceed to simplify the first two equations by
-    * eliminating what is likely to be the largest value, blue-scale:
-    *
-    *    blue-scale = white-scale - red-scale - green-scale
-    *
-    * Hence:
-    *
-    *    (red-x - blue-x)*red-scale + (green-x - blue-x)*green-scale =
-    *                (white-x - blue-x)*white-scale
-    *
-    *    (red-y - blue-y)*red-scale + (green-y - blue-y)*green-scale =
-    *                1 - blue-y*white-scale
-    *
-    * And now we can trivially solve for (red-scale,green-scale):
-    *
-    *    green-scale =
-    *                (white-x - blue-x)*white-scale - (red-x - blue-x)*red-scale
-    *                -----------------------------------------------------------
-    *                                  green-x - blue-x
-    *
-    *    red-scale =
-    *                1 - blue-y*white-scale - (green-y - blue-y) * green-scale
-    *                ---------------------------------------------------------
-    *                                  red-y - blue-y
-    *
-    * Hence:
-    *
-    *    red-scale =
-    *          ( (green-x - blue-x) * (white-y - blue-y) -
-    *            (green-y - blue-y) * (white-x - blue-x) ) / white-y
-    * -------------------------------------------------------------------------
-    *  (green-x - blue-x)*(red-y - blue-y)-(green-y - blue-y)*(red-x - blue-x)
-    *
-    *    green-scale =
-    *          ( (red-y - blue-y) * (white-x - blue-x) -
-    *            (red-x - blue-x) * (white-y - blue-y) ) / white-y
-    * -------------------------------------------------------------------------
-    *  (green-x - blue-x)*(red-y - blue-y)-(green-y - blue-y)*(red-x - blue-x)
-    *
-    * Accuracy:
-    * The input values have 5 decimal digits of accuracy.  The values are all in
-    * the range 0 < value < 1, so simple products are in the same range but may
-    * need up to 10 decimal digits to preserve the original precision and avoid
-    * underflow.  Because we are using a 32-bit signed representation we cannot
-    * match this; the best is a little over 9 decimal digits, less than 10.
-    *
-    * The approach used here is to preserve the maximum precision within the
-    * signed representation.  Because the red-scale calculation above uses the
-    * difference between two products of values that must be in the range -1..+1
-    * it is sufficient to divide the product by 7; ceil(100,000/32767*2).  The
-    * factor is irrelevant in the calculation because it is applied to both
-    * numerator and denominator.
-    *
-    * Note that the values of the differences of the products of the
-    * chromaticities in the above equations tend to be small, for example for
-    * the sRGB chromaticities they are:
-    *
-    * red numerator:    -0.04751
-    * green numerator:  -0.08788
-    * denominator:      -0.2241 (without white-y multiplication)
-    *
-    *  The resultant Y coefficients from the chromaticities of some widely used
-    *  color space definitions are (to 15 decimal places):
-    *
-    *  sRGB
-    *    0.212639005871510 0.715168678767756 0.072192315360734
-    *  Kodak ProPhoto
-    *    0.288071128229293 0.711843217810102 0.000085653960605
-    *  Adobe RGB
-    *    0.297344975250536 0.627363566255466 0.075291458493998
-    *  Adobe Wide Gamut RGB
-    *    0.258728243040113 0.724682314948566 0.016589442011321
-    */
-   /* By the argument, above overflow should be impossible here. The return
-    * value of 2 indicates an internal error to the caller.
-    */
-   if (!png_muldiv(&left, xy.greenx-xy.bluex, xy.redy - xy.bluey, 7)) return 2;
-   if (!png_muldiv(&right, xy.greeny-xy.bluey, xy.redx - xy.bluex, 7)) return 2;
-   denominator = left - right;
-
-   /* Now find the red numerator. */
-   if (!png_muldiv(&left, xy.greenx-xy.bluex, xy.whitey-xy.bluey, 7)) return 2;
-   if (!png_muldiv(&right, xy.greeny-xy.bluey, xy.whitex-xy.bluex, 7)) return 2;
-
-   /* Overflow is possible here and it indicates an extreme set of PNG cHRM
-    * chunk values.  This calculation actually returns the reciprocal of the
-    * scale value because this allows us to delay the multiplication of white-y
-    * into the denominator, which tends to produce a small number.
-    */
-   if (!png_muldiv(&red_inverse, xy.whitey, denominator, left-right) ||
-       red_inverse <= xy.whitey /* r+g+b scales = white scale */)
-      return 1;
-
-   /* Similarly for green_inverse: */
-   if (!png_muldiv(&left, xy.redy-xy.bluey, xy.whitex-xy.bluex, 7)) return 2;
-   if (!png_muldiv(&right, xy.redx-xy.bluex, xy.whitey-xy.bluey, 7)) return 2;
-   if (!png_muldiv(&green_inverse, xy.whitey, denominator, left-right) ||
-       green_inverse <= xy.whitey)
-      return 1;
-
-   /* And the blue scale, the checks above guarantee this can't overflow but it
-    * can still produce 0 for extreme cHRM values.
-    */
-   blue_scale = png_reciprocal(xy.whitey) - png_reciprocal(red_inverse) -
-      png_reciprocal(green_inverse);
-   if (blue_scale <= 0) return 1;
-
-
-   /* And fill in the png_XYZ: */
-   if (!png_muldiv(&XYZ->redX, xy.redx, PNG_FP_1, red_inverse)) return 1;
-   if (!png_muldiv(&XYZ->redY, xy.redy, PNG_FP_1, red_inverse)) return 1;
-   if (!png_muldiv(&XYZ->redZ, PNG_FP_1 - xy.redx - xy.redy, PNG_FP_1,
-      red_inverse))
-      return 1;
-
-   if (!png_muldiv(&XYZ->greenX, xy.greenx, PNG_FP_1, green_inverse)) return 1;
-   if (!png_muldiv(&XYZ->greenY, xy.greeny, PNG_FP_1, green_inverse)) return 1;
-   if (!png_muldiv(&XYZ->greenZ, PNG_FP_1 - xy.greenx - xy.greeny, PNG_FP_1,
-      green_inverse))
-      return 1;
-
-   if (!png_muldiv(&XYZ->blueX, xy.bluex, blue_scale, PNG_FP_1)) return 1;
-   if (!png_muldiv(&XYZ->blueY, xy.bluey, blue_scale, PNG_FP_1)) return 1;
-   if (!png_muldiv(&XYZ->blueZ, PNG_FP_1 - xy.bluex - xy.bluey, blue_scale,
-      PNG_FP_1))
-      return 1;
-
-   return 0; /*success*/
-}
-
-int png_XYZ_from_xy_checked(png_structp png_ptr, png_XYZ *XYZ, png_xy xy)
-{
-   switch (png_XYZ_from_xy(XYZ, xy))
-   {
-      case 0: /* success */
-         return 1;
-
-      case 1:
-         /* The chunk may be technically valid, but we got png_fixed_point
-          * overflow while trying to get XYZ values out of it.  This is
-          * entirely benign - the cHRM chunk is pretty extreme.
-          */
-         png_warning(png_ptr,
-            "extreme cHRM chunk cannot be converted to tristimulus values");
-         break;
-
-      default:
-         /* libpng is broken; this should be a warning but if it happens we
-          * want error reports so for the moment it is an error.
-          */
-         dg_png_error(png_ptr, "internal error in png_XYZ_from_xy");
-         break;
-   }
-
-   /* ERROR RETURN */
-   return 0;
-}
-#endif
-
-void /* PRIVATE */
-png_check_IHDR(png_structp png_ptr,
-   png_uint_32 width, png_uint_32 height, int bit_depth,
-   int color_type, int interlace_type, int compression_type,
-   int filter_type)
-{
-   int error = 0;
-
-   /* Check for width and height valid values */
-   if (width == 0)
-   {
-      png_warning(png_ptr, "Image width is zero in IHDR");
-      error = 1;
-   }
-
-   if (height == 0)
-   {
-      png_warning(png_ptr, "Image height is zero in IHDR");
-      error = 1;
-   }
-
-#  ifdef PNG_SET_USER_LIMITS_SUPPORTED
-   if (width > png_ptr->user_width_max)
-
-#  else
-   if (width > PNG_USER_WIDTH_MAX)
-#  endif
-   {
-      png_warning(png_ptr, "Image width exceeds user limit in IHDR");
-      error = 1;
-   }
-
-#  ifdef PNG_SET_USER_LIMITS_SUPPORTED
-   if (height > png_ptr->user_height_max)
-#  else
-   if (height > PNG_USER_HEIGHT_MAX)
-#  endif
-   {
-      png_warning(png_ptr, "Image height exceeds user limit in IHDR");
-      error = 1;
-   }
-
-   if (width > PNG_UINT_31_MAX)
-   {
-      png_warning(png_ptr, "Invalid image width in IHDR");
-      error = 1;
-   }
-
-   if (height > PNG_UINT_31_MAX)
-   {
-      png_warning(png_ptr, "Invalid image height in IHDR");
-      error = 1;
-   }
-
-   if (width > (PNG_UINT_32_MAX
-                 >> 3)      /* 8-byte RGBA pixels */
-                 - 48       /* bigrowbuf hack */
-                 - 1        /* filter byte */
-                 - 7*8      /* rounding of width to multiple of 8 pixels */
-                 - 8)       /* extra max_pixel_depth pad */
-      png_warning(png_ptr, "Width is too large for libpng to process pixels");
-
-   /* Check other values */
-   if (bit_depth != 1 && bit_depth != 2 && bit_depth != 4 &&
-       bit_depth != 8 && bit_depth != 16)
-   {
-      png_warning(png_ptr, "Invalid bit depth in IHDR");
-      error = 1;
-   }
-
-   if (color_type < 0 || color_type == 1 ||
-       color_type == 5 || color_type > 6)
-   {
-      png_warning(png_ptr, "Invalid color type in IHDR");
-      error = 1;
-   }
-
-   if (((color_type == PNG_COLOR_TYPE_PALETTE) && bit_depth > 8) ||
-       ((color_type == PNG_COLOR_TYPE_RGB ||
-         color_type == PNG_COLOR_TYPE_GRAY_ALPHA ||
-         color_type == PNG_COLOR_TYPE_RGB_ALPHA) && bit_depth < 8))
-   {
-      png_warning(png_ptr, "Invalid color type/bit depth combination in IHDR");
-      error = 1;
-   }
-
-   if (interlace_type >= PNG_INTERLACE_LAST)
-   {
-      png_warning(png_ptr, "Unknown interlace method in IHDR");
-      error = 1;
-   }
-
-   if (compression_type != PNG_COMPRESSION_TYPE_BASE)
-   {
-      png_warning(png_ptr, "Unknown compression method in IHDR");
-      error = 1;
-   }
-
-#  ifdef PNG_MNG_FEATURES_SUPPORTED
-   /* Accept filter_method 64 (intrapixel differencing) only if
-    * 1. Libpng was compiled with PNG_MNG_FEATURES_SUPPORTED and
-    * 2. Libpng did not read a PNG signature (this filter_method is only
-    *    used in PNG datastreams that are embedded in MNG datastreams) and
-    * 3. The application called png_permit_mng_features with a mask that
-    *    included PNG_FLAG_MNG_FILTER_64 and
-    * 4. The filter_method is 64 and
-    * 5. The color_type is RGB or RGBA
-    */
-   if ((png_ptr->mode & PNG_HAVE_PNG_SIGNATURE) &&
-       png_ptr->mng_features_permitted)
-      png_warning(png_ptr, "MNG features are not allowed in a PNG datastream");
-
-   if (filter_type != PNG_FILTER_TYPE_BASE)
-   {
-      if (!((png_ptr->mng_features_permitted & PNG_FLAG_MNG_FILTER_64) &&
-          (filter_type == PNG_INTRAPIXEL_DIFFERENCING) &&
-          ((png_ptr->mode & PNG_HAVE_PNG_SIGNATURE) == 0) &&
-          (color_type == PNG_COLOR_TYPE_RGB ||
-          color_type == PNG_COLOR_TYPE_RGB_ALPHA)))
-      {
-         png_warning(png_ptr, "Unknown filter method in IHDR");
-         error = 1;
-      }
-
-      if (png_ptr->mode & PNG_HAVE_PNG_SIGNATURE)
-      {
-         png_warning(png_ptr, "Invalid filter method in IHDR");
-         error = 1;
-      }
-   }
-
-#  else
-   if (filter_type != PNG_FILTER_TYPE_BASE)
-   {
-      png_warning(png_ptr, "Unknown filter method in IHDR");
-      error = 1;
-   }
-#  endif
-
-   if (error == 1)
-      dg_png_error(png_ptr, "Invalid IHDR data");
-}
-
-#if defined(PNG_sCAL_SUPPORTED) || defined(PNG_pCAL_SUPPORTED)
-/* ASCII to fp functions */
-/* Check an ASCII formated floating point value, see the more detailed
- * comments in pngpriv.h
- */
-/* The following is used internally to preserve the sticky flags */
-#define png_fp_add(state, flags) ((state) |= (flags))
-#define png_fp_set(state, value) ((state) = (value) | ((state) & PNG_FP_STICKY))
-
-int /* PRIVATE */
-png_check_fp_number(png_const_charp string, png_size_t size, int *statep,
-   png_size_tp whereami)
-{
-   int state = *statep;
-   png_size_t i = *whereami;
-
-   while (i < size)
-   {
-      int type;
-      /* First find the type of the next character */
-      switch (string[i])
-      {
-      case 43:  type = PNG_FP_SAW_SIGN;                   break;
-      case 45:  type = PNG_FP_SAW_SIGN + PNG_FP_NEGATIVE; break;
-      case 46:  type = PNG_FP_SAW_DOT;                    break;
-      case 48:  type = PNG_FP_SAW_DIGIT;                  break;
-      case 49: case 50: case 51: case 52:
-      case 53: case 54: case 55: case 56:
-      case 57:  type = PNG_FP_SAW_DIGIT + PNG_FP_NONZERO; break;
-      case 69:
-      case 101: type = PNG_FP_SAW_E;                      break;
-      default:  goto PNG_FP_End;
-      }
-
-      /* Now deal with this type according to the current
-       * state, the type is arranged to not overlap the
-       * bits of the PNG_FP_STATE.
-       */
-      switch ((state & PNG_FP_STATE) + (type & PNG_FP_SAW_ANY))
-      {
-      case PNG_FP_INTEGER + PNG_FP_SAW_SIGN:
-         if (state & PNG_FP_SAW_ANY)
-            goto PNG_FP_End; /* not a part of the number */
-
-         png_fp_add(state, type);
-         break;
-
-      case PNG_FP_INTEGER + PNG_FP_SAW_DOT:
-         /* Ok as trailer, ok as lead of fraction. */
-         if (state & PNG_FP_SAW_DOT) /* two dots */
-            goto PNG_FP_End;
-
-         else if (state & PNG_FP_SAW_DIGIT) /* trailing dot? */
-            png_fp_add(state, type);
-
-         else
-            png_fp_set(state, PNG_FP_FRACTION | type);
-
-         break;
-
-      case PNG_FP_INTEGER + PNG_FP_SAW_DIGIT:
-         if (state & PNG_FP_SAW_DOT) /* delayed fraction */
-            png_fp_set(state, PNG_FP_FRACTION | PNG_FP_SAW_DOT);
-
-         png_fp_add(state, type | PNG_FP_WAS_VALID);
-
-         break;
-
-      case PNG_FP_INTEGER + PNG_FP_SAW_E:
-         if ((state & PNG_FP_SAW_DIGIT) == 0)
-            goto PNG_FP_End;
-
-         png_fp_set(state, PNG_FP_EXPONENT);
-
-         break;
-
-   /* case PNG_FP_FRACTION + PNG_FP_SAW_SIGN:
-         goto PNG_FP_End; ** no sign in fraction */
-
-   /* case PNG_FP_FRACTION + PNG_FP_SAW_DOT:
-         goto PNG_FP_End; ** Because SAW_DOT is always set */
-
-      case PNG_FP_FRACTION + PNG_FP_SAW_DIGIT:
-         png_fp_add(state, type | PNG_FP_WAS_VALID);
-         break;
-
-      case PNG_FP_FRACTION + PNG_FP_SAW_E:
-         /* This is correct because the trailing '.' on an
-          * integer is handled above - so we can only get here
-          * with the sequence ".E" (with no preceding digits).
-          */
-         if ((state & PNG_FP_SAW_DIGIT) == 0)
-            goto PNG_FP_End;
-
-         png_fp_set(state, PNG_FP_EXPONENT);
-
-         break;
-
-      case PNG_FP_EXPONENT + PNG_FP_SAW_SIGN:
-         if (state & PNG_FP_SAW_ANY)
-            goto PNG_FP_End; /* not a part of the number */
-
-         png_fp_add(state, PNG_FP_SAW_SIGN);
-
-         break;
-
-   /* case PNG_FP_EXPONENT + PNG_FP_SAW_DOT:
-         goto PNG_FP_End; */
-
-      case PNG_FP_EXPONENT + PNG_FP_SAW_DIGIT:
-         png_fp_add(state, PNG_FP_SAW_DIGIT | PNG_FP_WAS_VALID);
-
-         break;
-
-   /* case PNG_FP_EXPONEXT + PNG_FP_SAW_E:
-         goto PNG_FP_End; */
-
-      default: goto PNG_FP_End; /* I.e. break 2 */
-      }
-
-      /* The character seems ok, continue. */
-      ++i;
-   }
-
-PNG_FP_End:
-   /* Here at the end, update the state and return the correct
-    * return code.
-    */
-   *statep = state;
-   *whereami = i;
-
-   return (state & PNG_FP_SAW_DIGIT) != 0;
-}
-
-
-/* The same but for a complete string. */
-int
-png_check_fp_string(png_const_charp string, png_size_t size)
-{
-   int        state=0;
-   png_size_t char_index=0;
-
-   if (png_check_fp_number(string, size, &state, &char_index) &&
-      (char_index == size || string[char_index] == 0))
-      return state /* must be non-zero - see above */;
-
-   return 0; /* i.e. fail */
-}
-#endif /* pCAL or sCAL */
-
-#ifdef PNG_READ_sCAL_SUPPORTED
-#  ifdef PNG_FLOATING_POINT_SUPPORTED
-/* Utility used below - a simple accurate power of ten from an integral
- * exponent.
- */
-static double
-png_pow10(int power)
-{
-   int recip = 0;
-   double d = 1.0;
-
-   /* Handle negative exponent with a reciprocal at the end because
-    * 10 is exact whereas .1 is inexact in base 2
-    */
-   if (power < 0)
-   {
-      if (power < DBL_MIN_10_EXP) return 0;
-      recip = 1, power = -power;
-   }
-
-   if (power > 0)
-   {
-      /* Decompose power bitwise. */
-      double mult = 10.0;
-      do
-      {
-         if (power & 1) d *= mult;
-         mult *= mult;
-         power >>= 1;
-      }
-      while (power > 0);
-
-      if (recip) d = 1/d;
-   }
-   /* else power is 0 and d is 1 */
-
-   return d;
-}
-
-/* Function to format a floating point value in ASCII with a given
- * precision.
- */
-void /* PRIVATE */
-png_ascii_from_fp(png_structp png_ptr, png_charp ascii, png_size_t size,
-    double fp, unsigned int precision)
-{
-   /* We use standard functions from math.h, but not printf because
-    * that would require stdio.  The caller must supply a buffer of
-    * sufficient size or we will png_error.  The tests on size and
-    * the space in ascii[] consumed are indicated below.
-    */
-   if (precision < 1)
-      precision = DBL_DIG;
-
-   /* Enforce the limit of the implementation precision too. */
-   if (precision > DBL_DIG+1)
-      precision = DBL_DIG+1;
-
-   /* Basic sanity checks */
-   if (size >= precision+5) /* See the requirements below. */
-   {
-      if (fp < 0)
-      {
-         fp = -fp;
-         *ascii++ = 45; /* '-'  PLUS 1 TOTAL 1 */
-         --size;
-      }
-
-      if (fp >= DBL_MIN && fp <= DBL_MAX)
-      {
-         int exp_b10;       /* A base 10 exponent */
-         double base;   /* 10^exp_b10 */
-
-         /* First extract a base 10 exponent of the number,
-          * the calculation below rounds down when converting
-          * from base 2 to base 10 (multiply by log10(2) -
-          * 0.3010, but 77/256 is 0.3008, so exp_b10 needs to
-          * be increased.  Note that the arithmetic shift
-          * performs a floor() unlike C arithmetic - using a
-          * C multiply would break the following for negative
-          * exponents.
-          */
-         (void)frexp(fp, &exp_b10); /* exponent to base 2 */
-
-         exp_b10 = (exp_b10 * 77) >> 8; /* <= exponent to base 10 */
-
-         /* Avoid underflow here. */
-         base = png_pow10(exp_b10); /* May underflow */
-
-         while (base < DBL_MIN || base < fp)
-         {
-            /* And this may overflow. */
-            double test = png_pow10(exp_b10+1);
-
-            if (test <= DBL_MAX)
-               ++exp_b10, base = test;
-
-            else
-               break;
-         }
-
-         /* Normalize fp and correct exp_b10, after this fp is in the
-          * range [.1,1) and exp_b10 is both the exponent and the digit
-          * *before* which the decimal point should be inserted
-          * (starting with 0 for the first digit).  Note that this
-          * works even if 10^exp_b10 is out of range because of the
-          * test on DBL_MAX above.
-          */
-         fp /= base;
-         while (fp >= 1) fp /= 10, ++exp_b10;
-
-         /* Because of the code above fp may, at this point, be
-          * less than .1, this is ok because the code below can
-          * handle the leading zeros this generates, so no attempt
-          * is made to correct that here.
-          */
-
-         {
-            int czero, clead, cdigits;
-            char exponent[10];
-
-            /* Allow up to two leading zeros - this will not lengthen
-             * the number compared to using E-n.
-             */
-            if (exp_b10 < 0 && exp_b10 > -3) /* PLUS 3 TOTAL 4 */
-            {
-               czero = -exp_b10; /* PLUS 2 digits: TOTAL 3 */
-               exp_b10 = 0;      /* Dot added below before first output. */
-            }
-            else
-               czero = 0;    /* No zeros to add */
-
-            /* Generate the digit list, stripping trailing zeros and
-             * inserting a '.' before a digit if the exponent is 0.
-             */
-            clead = czero; /* Count of leading zeros */
-            cdigits = 0;   /* Count of digits in list. */
-
-            do
-            {
-               double d;
-
-               fp *= 10.0;
-
-               /* Use modf here, not floor and subtract, so that
-                * the separation is done in one step.  At the end
-                * of the loop don't break the number into parts so
-                * that the final digit is rounded.
-                */
-               if (cdigits+czero-clead+1 < (int)precision)
-                  fp = modf(fp, &d);
-
-               else
-               {
-                  d = floor(fp + .5);
-
-                  if (d > 9.0)
-                  {
-                     /* Rounding up to 10, handle that here. */
-                     if (czero > 0)
-                     {
-                        --czero, d = 1;
-                        if (cdigits == 0) --clead;
-                     }
-
-                     else
-                     {
-                        while (cdigits > 0 && d > 9.0)
-                        {
-                           int ch = *--ascii;
-
-                           if (exp_b10 != (-1))
-                              ++exp_b10;
-
-                           else if (ch == 46)
-                           {
-                              ch = *--ascii, ++size;
-                              /* Advance exp_b10 to '1', so that the
-                               * decimal point happens after the
-                               * previous digit.
-                               */
-                              exp_b10 = 1;
-                           }
-
-                           --cdigits;
-                           d = ch - 47;  /* I.e. 1+(ch-48) */
-                        }
-
-                        /* Did we reach the beginning? If so adjust the
-                         * exponent but take into account the leading
-                         * decimal point.
-                         */
-                        if (d > 9.0)  /* cdigits == 0 */
-                        {
-                           if (exp_b10 == (-1))
-                           {
-                              /* Leading decimal point (plus zeros?), if
-                               * we lose the decimal point here it must
-                               * be reentered below.
-                               */
-                              int ch = *--ascii;
-
-                              if (ch == 46)
-                                 ++size, exp_b10 = 1;
-
-                              /* Else lost a leading zero, so 'exp_b10' is
-                               * still ok at (-1)
-                               */
-                           }
-                           else
-                              ++exp_b10;
-
-                           /* In all cases we output a '1' */
-                           d = 1.0;
-                        }
-                     }
-                  }
-                  fp = 0; /* Guarantees termination below. */
-               }
-
-               if (d == 0.0)
-               {
-                  ++czero;
-                  if (cdigits == 0) ++clead;
-               }
-
-               else
-               {
-                  /* Included embedded zeros in the digit count. */
-                  cdigits += czero - clead;
-                  clead = 0;
-
-                  while (czero > 0)
-                  {
-                     /* exp_b10 == (-1) means we just output the decimal
-                      * place - after the DP don't adjust 'exp_b10' any
-                      * more!
-                      */
-                     if (exp_b10 != (-1))
-                     {
-                        if (exp_b10 == 0) *ascii++ = 46, --size;
-                        /* PLUS 1: TOTAL 4 */
-                        --exp_b10;
-                     }
-                     *ascii++ = 48, --czero;
-                  }
-
-                  if (exp_b10 != (-1))
-                  {
-                     if (exp_b10 == 0) *ascii++ = 46, --size; /* counted
-                                                                 above */
-                     --exp_b10;
-                  }
-
-                  *ascii++ = (char)(48 + (int)d), ++cdigits;
-               }
-            }
-            while (cdigits+czero-clead < (int)precision && fp > DBL_MIN);
-
-            /* The total output count (max) is now 4+precision */
-
-            /* Check for an exponent, if we don't need one we are
-             * done and just need to terminate the string.  At
-             * this point exp_b10==(-1) is effectively if flag - it got
-             * to '-1' because of the decrement after outputing
-             * the decimal point above (the exponent required is
-             * *not* -1!)
-             */
-            if (exp_b10 >= (-1) && exp_b10 <= 2)
-            {
-               /* The following only happens if we didn't output the
-                * leading zeros above for negative exponent, so this
-                * doest add to the digit requirement.  Note that the
-                * two zeros here can only be output if the two leading
-                * zeros were *not* output, so this doesn't increase
-                * the output count.
-                */
-               while (--exp_b10 >= 0) *ascii++ = 48;
-
-               *ascii = 0;
-
-               /* Total buffer requirement (including the '\0') is
-                * 5+precision - see check at the start.
-                */
-               return;
-            }
-
-            /* Here if an exponent is required, adjust size for
-             * the digits we output but did not count.  The total
-             * digit output here so far is at most 1+precision - no
-             * decimal point and no leading or trailing zeros have
-             * been output.
-             */
-            size -= cdigits;
-
-            *ascii++ = 69, --size;    /* 'E': PLUS 1 TOTAL 2+precision */
-
-            /* The following use of an unsigned temporary avoids ambiguities in
-             * the signed arithmetic on exp_b10 and permits GCC at least to do
-             * better optimization.
-             */
-            {
-               unsigned int uexp_b10;
-
-               if (exp_b10 < 0)
-               {
-                  *ascii++ = 45, --size; /* '-': PLUS 1 TOTAL 3+precision */
-                  uexp_b10 = -exp_b10;
-               }
-
-               else
-                  uexp_b10 = exp_b10;
-
-               cdigits = 0;
-
-               while (uexp_b10 > 0)
-               {
-                  exponent[cdigits++] = (char)(48 + uexp_b10 % 10);
-                  uexp_b10 /= 10;
-               }
-            }
-
-            /* Need another size check here for the exponent digits, so
-             * this need not be considered above.
-             */
-            if ((int)size > cdigits)
-            {
-               while (cdigits > 0) *ascii++ = exponent[--cdigits];
-
-               *ascii = 0;
-
-               return;
-            }
-         }
-      }
-      else if (!(fp >= DBL_MIN))
-      {
-         *ascii++ = 48; /* '0' */
-         *ascii = 0;
-         return;
-      }
-      else
-      {
-         *ascii++ = 105; /* 'i' */
-         *ascii++ = 110; /* 'n' */
-         *ascii++ = 102; /* 'f' */
-         *ascii = 0;
-         return;
-      }
-   }
-
-   /* Here on buffer too small. */
-   dg_png_error(png_ptr, "ASCII conversion buffer too small");
-}
-
-#  endif /* FLOATING_POINT */
-
-#  ifdef PNG_FIXED_POINT_SUPPORTED
-/* Function to format a fixed point value in ASCII.
- */
-void /* PRIVATE */
-png_ascii_from_fixed(png_structp png_ptr, png_charp ascii, png_size_t size,
-    png_fixed_point fp)
-{
-   /* Require space for 10 decimal digits, a decimal point, a minus sign and a
-    * trailing \0, 13 characters:
-    */
-   if (size > 12)
-   {
-      png_uint_32 num;
-
-      /* Avoid overflow here on the minimum integer. */
-      if (fp < 0)
-         *ascii++ = 45, --size, num = -fp;
-      else
-         num = fp;
-
-      if (num <= 0x80000000) /* else overflowed */
-      {
-         unsigned int ndigits = 0, first = 16 /* flag value */;
-         char digits[10];
-
-         while (num)
-         {
-            /* Split the low digit off num: */
-            unsigned int tmp = num/10;
-            num -= tmp*10;
-            digits[ndigits++] = (char)(48 + num);
-            /* Record the first non-zero digit, note that this is a number
-             * starting at 1, it's not actually the array index.
-             */
-            if (first == 16 && num > 0)
-               first = ndigits;
-            num = tmp;
-         }
-
-         if (ndigits > 0)
-         {
-            while (ndigits > 5) *ascii++ = digits[--ndigits];
-            /* The remaining digits are fractional digits, ndigits is '5' or
-             * smaller at this point.  It is certainly not zero.  Check for a
-             * non-zero fractional digit:
-             */
-            if (first <= 5)
-            {
-               unsigned int i;
-               *ascii++ = 46; /* decimal point */
-               /* ndigits may be <5 for small numbers, output leading zeros
-                * then ndigits digits to first:
-                */
-               i = 5;
-               while (ndigits < i) *ascii++ = 48, --i;
-               while (ndigits >= first) *ascii++ = digits[--ndigits];
-               /* Don't output the trailing zeros! */
-            }
-         }
-         else
-            *ascii++ = 48;
-
-         /* And null terminate the string: */
-         *ascii = 0;
-         return;
-      }
-   }
-
-   /* Here on buffer too small. */
-   dg_png_error(png_ptr, "ASCII conversion buffer too small");
-}
-#   endif /* FIXED_POINT */
-#endif /* READ_SCAL */
-
-#if defined(PNG_FLOATING_POINT_SUPPORTED) && \
-   !defined(PNG_FIXED_POINT_MACRO_SUPPORTED)
-png_fixed_point
-png_fixed(png_structp png_ptr, double fp, png_const_charp text)
-{
-   double r = floor(100000 * fp + .5);
-
-   if (r > 2147483647. || r < -2147483648.)
-      png_fixed_error(png_ptr, text);
-
-   return (png_fixed_point)r;
-}
-#endif
-
-#if defined(PNG_READ_GAMMA_SUPPORTED) || \
-    defined(PNG_INCH_CONVERSIONS_SUPPORTED) || defined(PNG__READ_pHYs_SUPPORTED)
-/* muldiv functions */
-/* This API takes signed arguments and rounds the result to the nearest
- * integer (or, for a fixed point number - the standard argument - to
- * the nearest .00001).  Overflow and divide by zero are signalled in
- * the result, a boolean - true on success, false on overflow.
- */
-int
-png_muldiv(png_fixed_point_p res, png_fixed_point a, png_int_32 times,
-    png_int_32 divisor)
-{
-   /* Return a * times / divisor, rounded. */
-   if (divisor != 0)
-   {
-      if (a == 0 || times == 0)
-      {
-         *res = 0;
-         return 1;
-      }
-      else
-      {
-#ifdef PNG_FLOATING_ARITHMETIC_SUPPORTED
-         double r = a;
-         r *= times;
-         r /= divisor;
-         r = floor(r+.5);
-
-         /* A png_fixed_point is a 32-bit integer. */
-         if (r <= 2147483647. && r >= -2147483648.)
-         {
-            *res = (png_fixed_point)r;
-            return 1;
-         }
-#else
-         int negative = 0;
-         png_uint_32 A, T, D;
-         png_uint_32 s16, s32, s00;
-
-         if (a < 0)
-            negative = 1, A = -a;
-         else
-            A = a;
-
-         if (times < 0)
-            negative = !negative, T = -times;
-         else
-            T = times;
-
-         if (divisor < 0)
-            negative = !negative, D = -divisor;
-         else
-            D = divisor;
-
-         /* Following can't overflow because the arguments only
-          * have 31 bits each, however the result may be 32 bits.
-          */
-         s16 = (A >> 16) * (T & 0xffff) +
-                           (A & 0xffff) * (T >> 16);
-         /* Can't overflow because the a*times bit is only 30
-          * bits at most.
-          */
-         s32 = (A >> 16) * (T >> 16) + (s16 >> 16);
-         s00 = (A & 0xffff) * (T & 0xffff);
-
-         s16 = (s16 & 0xffff) << 16;
-         s00 += s16;
-
-         if (s00 < s16)
-            ++s32; /* carry */
-
-         if (s32 < D) /* else overflow */
-         {
-            /* s32.s00 is now the 64-bit product, do a standard
-             * division, we know that s32 < D, so the maximum
-             * required shift is 31.
-             */
-            int bitshift = 32;
-            png_fixed_point result = 0; /* NOTE: signed */
-
-            while (--bitshift >= 0)
-            {
-               png_uint_32 d32, d00;
-
-               if (bitshift > 0)
-                  d32 = D >> (32-bitshift), d00 = D << bitshift;
-
-               else
-                  d32 = 0, d00 = D;
-
-               if (s32 > d32)
-               {
-                  if (s00 < d00) --s32; /* carry */
-                  s32 -= d32, s00 -= d00, result += 1<<bitshift;
-               }
-
-               else
-                  if (s32 == d32 && s00 >= d00)
-                     s32 = 0, s00 -= d00, result += 1<<bitshift;
-            }
-
-            /* Handle the rounding. */
-            if (s00 >= (D >> 1))
-               ++result;
-
-            if (negative)
-               result = -result;
-
-            /* Check for overflow. */
-            if ((negative && result <= 0) || (!negative && result >= 0))
-            {
-               *res = result;
-               return 1;
-            }
-         }
-#endif
-      }
-   }
-
-   return 0;
-}
-#endif /* READ_GAMMA || INCH_CONVERSIONS */
-
-#if defined(PNG_READ_GAMMA_SUPPORTED) || defined(PNG_INCH_CONVERSIONS_SUPPORTED)
-/* The following is for when the caller doesn't much care about the
- * result.
- */
-png_fixed_point
-png_muldiv_warn(png_structp png_ptr, png_fixed_point a, png_int_32 times,
-    png_int_32 divisor)
-{
-   png_fixed_point result;
-
-   if (png_muldiv(&result, a, times, divisor))
-      return result;
-
-   png_warning(png_ptr, "fixed point overflow ignored");
-   return 0;
-}
-#endif
-
-#ifdef PNG_READ_GAMMA_SUPPORTED /* more fixed point functions for gamma */
-/* Calculate a reciprocal, return 0 on div-by-zero or overflow. */
-png_fixed_point
-png_reciprocal(png_fixed_point a)
-{
-#ifdef PNG_FLOATING_ARITHMETIC_SUPPORTED
-   double r = floor(1E10/a+.5);
-
-   if (r <= 2147483647. && r >= -2147483648.)
-      return (png_fixed_point)r;
-#else
-   png_fixed_point res;
-
-   if (png_muldiv(&res, 100000, 100000, a))
-      return res;
-#endif
-
-   return 0; /* error/overflow */
-}
-
-/* A local convenience routine. */
-static png_fixed_point
-png_product2(png_fixed_point a, png_fixed_point b)
-{
-   /* The required result is 1/a * 1/b; the following preserves accuracy. */
-#ifdef PNG_FLOATING_ARITHMETIC_SUPPORTED
-   double r = a * 1E-5;
-   r *= b;
-   r = floor(r+.5);
-
-   if (r <= 2147483647. && r >= -2147483648.)
-      return (png_fixed_point)r;
-#else
-   png_fixed_point res;
-
-   if (png_muldiv(&res, a, b, 100000))
-      return res;
-#endif
-
-   return 0; /* overflow */
-}
-
-/* The inverse of the above. */
-png_fixed_point
-png_reciprocal2(png_fixed_point a, png_fixed_point b)
-{
-   /* The required result is 1/a * 1/b; the following preserves accuracy. */
-#ifdef PNG_FLOATING_ARITHMETIC_SUPPORTED
-   double r = 1E15/a;
-   r /= b;
-   r = floor(r+.5);
-
-   if (r <= 2147483647. && r >= -2147483648.)
-      return (png_fixed_point)r;
-#else
-   /* This may overflow because the range of png_fixed_point isn't symmetric,
-    * but this API is only used for the product of file and screen gamma so it
-    * doesn't matter that the smallest number it can produce is 1/21474, not
-    * 1/100000
-    */
-   png_fixed_point res = png_product2(a, b);
-
-   if (res != 0)
-      return png_reciprocal(res);
-#endif
-
-   return 0; /* overflow */
-}
-#endif /* READ_GAMMA */
-
-#ifdef PNG_CHECK_cHRM_SUPPORTED
-/* Added at libpng version 1.2.34 (Dec 8, 2008) and 1.4.0 (Jan 2,
- * 2010: moved from pngset.c) */
-/*
- *    Multiply two 32-bit numbers, V1 and V2, using 32-bit
- *    arithmetic, to produce a 64-bit result in the HI/LO words.
- *
- *                  A B
- *                x C D
- *               ------
- *              AD || BD
- *        AC || CB || 0
- *
- *    where A and B are the high and low 16-bit words of V1,
- *    C and D are the 16-bit words of V2, AD is the product of
- *    A and D, and X || Y is (X << 16) + Y.
-*/
-
-void /* PRIVATE */
-png_64bit_product (long v1, long v2, unsigned long *hi_product,
-    unsigned long *lo_product)
-{
-   int a, b, c, d;
-   long lo, hi, x, y;
-
-   a = (v1 >> 16) & 0xffff;
-   b = v1 & 0xffff;
-   c = (v2 >> 16) & 0xffff;
-   d = v2 & 0xffff;
-
-   lo = b * d;                   /* BD */
-   x = a * d + c * b;            /* AD + CB */
-   y = ((lo >> 16) & 0xffff) + x;
-
-   lo = (lo & 0xffff) | ((y & 0xffff) << 16);
-   hi = (y >> 16) & 0xffff;
-
-   hi += a * c;                  /* AC */
-
-   *hi_product = (unsigned long)hi;
-   *lo_product = (unsigned long)lo;
-}
-#endif /* CHECK_cHRM */
-
-#ifdef PNG_READ_GAMMA_SUPPORTED /* gamma table code */
-#ifndef PNG_FLOATING_ARITHMETIC_SUPPORTED
-/* Fixed point gamma.
- *
- * To calculate gamma this code implements fast log() and exp() calls using only
- * fixed point arithmetic.  This code has sufficient precision for either 8-bit
- * or 16-bit sample values.
- *
- * The tables used here were calculated using simple 'bc' programs, but C double
- * precision floating point arithmetic would work fine.  The programs are given
- * at the head of each table.
- *
- * 8-bit log table
- *   This is a table of -log(value/255)/log(2) for 'value' in the range 128 to
- *   255, so it's the base 2 logarithm of a normalized 8-bit floating point
- *   mantissa.  The numbers are 32-bit fractions.
- */
-static png_uint_32
-png_8bit_l2[128] =
-{
-#  ifdef PNG_DO_BC
-      for (i=128;i<256;++i) { .5 - l(i/255)/l(2)*65536*65536; }
-#  else
-   4270715492U, 4222494797U, 4174646467U, 4127164793U, 4080044201U, 4033279239U,
-   3986864580U, 3940795015U, 3895065449U, 3849670902U, 3804606499U, 3759867474U,
-   3715449162U, 3671346997U, 3627556511U, 3584073329U, 3540893168U, 3498011834U,
-   3455425220U, 3413129301U, 3371120137U, 3329393864U, 3287946700U, 3246774933U,
-   3205874930U, 3165243125U, 3124876025U, 3084770202U, 3044922296U, 3005329011U,
-   2965987113U, 2926893432U, 2888044853U, 2849438323U, 2811070844U, 2772939474U,
-   2735041326U, 2697373562U, 2659933400U, 2622718104U, 2585724991U, 2548951424U,
-   2512394810U, 2476052606U, 2439922311U, 2404001468U, 2368287663U, 2332778523U,
-   2297471715U, 2262364947U, 2227455964U, 2192742551U, 2158222529U, 2123893754U,
-   2089754119U, 2055801552U, 2022034013U, 1988449497U, 1955046031U, 1921821672U,
-   1888774511U, 1855902668U, 1823204291U, 1790677560U, 1758320682U, 1726131893U,
-   1694109454U, 1662251657U, 1630556815U, 1599023271U, 1567649391U, 1536433567U,
-   1505374214U, 1474469770U, 1443718700U, 1413119487U, 1382670639U, 1352370686U,
-   1322218179U, 1292211689U, 1262349810U, 1232631153U, 1203054352U, 1173618059U,
-   1144320946U, 1115161701U, 1086139034U, 1057251672U, 1028498358U, 999877854U,
-   971388940U, 943030410U, 914801076U, 886699767U, 858725327U, 830876614U,
-   803152505U, 775551890U, 748073672U, 720716771U, 693480120U, 666362667U,
-   639363374U, 612481215U, 585715177U, 559064263U, 532527486U, 506103872U,
-   479792461U, 453592303U, 427502463U, 401522014U, 375650043U, 349885648U,
-   324227938U, 298676034U, 273229066U, 247886176U, 222646516U, 197509248U,
-   172473545U, 147538590U, 122703574U, 97967701U, 73330182U, 48790236U,
-   24347096U, 0U
-#  endif
-
-#if 0
-   /* The following are the values for 16-bit tables - these work fine for the
-    * 8-bit conversions but produce very slightly larger errors in the 16-bit
-    * log (about 1.2 as opposed to 0.7 absolute error in the final value).  To
-    * use these all the shifts below must be adjusted appropriately.
-    */
-   65166, 64430, 63700, 62976, 62257, 61543, 60835, 60132, 59434, 58741, 58054,
-   57371, 56693, 56020, 55352, 54689, 54030, 53375, 52726, 52080, 51439, 50803,
-   50170, 49542, 48918, 48298, 47682, 47070, 46462, 45858, 45257, 44661, 44068,
-   43479, 42894, 42312, 41733, 41159, 40587, 40020, 39455, 38894, 38336, 37782,
-   37230, 36682, 36137, 35595, 35057, 34521, 33988, 33459, 32932, 32408, 31887,
-   31369, 30854, 30341, 29832, 29325, 28820, 28319, 27820, 27324, 26830, 26339,
-   25850, 25364, 24880, 24399, 23920, 23444, 22970, 22499, 22029, 21562, 21098,
-   20636, 20175, 19718, 19262, 18808, 18357, 17908, 17461, 17016, 16573, 16132,
-   15694, 15257, 14822, 14390, 13959, 13530, 13103, 12678, 12255, 11834, 11415,
-   10997, 10582, 10168, 9756, 9346, 8937, 8531, 8126, 7723, 7321, 6921, 6523,
-   6127, 5732, 5339, 4947, 4557, 4169, 3782, 3397, 3014, 2632, 2251, 1872, 1495,
-   1119, 744, 372
-#endif
-};
-
-PNG_STATIC png_int_32
-png_log8bit(unsigned int x)
-{
-   unsigned int lg2 = 0;
-   /* Each time 'x' is multiplied by 2, 1 must be subtracted off the final log,
-    * because the log is actually negate that means adding 1.  The final
-    * returned value thus has the range 0 (for 255 input) to 7.994 (for 1
-    * input), return 7.99998 for the overflow (log 0) case - so the result is
-    * always at most 19 bits.
-    */
-   if ((x &= 0xff) == 0)
-      return 0xffffffff;
-
-   if ((x & 0xf0) == 0)
-      lg2  = 4, x <<= 4;
-
-   if ((x & 0xc0) == 0)
-      lg2 += 2, x <<= 2;
-
-   if ((x & 0x80) == 0)
-      lg2 += 1, x <<= 1;
-
-   /* result is at most 19 bits, so this cast is safe: */
-   return (png_int_32)((lg2 << 16) + ((png_8bit_l2[x-128]+32768)>>16));
-}
-
-/* The above gives exact (to 16 binary places) log2 values for 8-bit images,
- * for 16-bit images we use the most significant 8 bits of the 16-bit value to
- * get an approximation then multiply the approximation by a correction factor
- * determined by the remaining up to 8 bits.  This requires an additional step
- * in the 16-bit case.
- *
- * We want log2(value/65535), we have log2(v'/255), where:
- *
- *    value = v' * 256 + v''
- *          = v' * f
- *
- * So f is value/v', which is equal to (256+v''/v') since v' is in the range 128
- * to 255 and v'' is in the range 0 to 255 f will be in the range 256 to less
- * than 258.  The final factor also needs to correct for the fact that our 8-bit
- * value is scaled by 255, whereas the 16-bit values must be scaled by 65535.
- *
- * This gives a final formula using a calculated value 'x' which is value/v' and
- * scaling by 65536 to match the above table:
- *
- *   log2(x/257) * 65536
- *
- * Since these numbers are so close to '1' we can use simple linear
- * interpolation between the two end values 256/257 (result -368.61) and 258/257
- * (result 367.179).  The values used below are scaled by a further 64 to give
- * 16-bit precision in the interpolation:
- *
- * Start (256): -23591
- * Zero  (257):      0
- * End   (258):  23499
- */
-PNG_STATIC png_int_32
-png_log16bit(png_uint_32 x)
-{
-   unsigned int lg2 = 0;
-
-   /* As above, but now the input has 16 bits. */
-   if ((x &= 0xffff) == 0)
-      return 0xffffffff;
-
-   if ((x & 0xff00) == 0)
-      lg2  = 8, x <<= 8;
-
-   if ((x & 0xf000) == 0)
-      lg2 += 4, x <<= 4;
-
-   if ((x & 0xc000) == 0)
-      lg2 += 2, x <<= 2;
-
-   if ((x & 0x8000) == 0)
-      lg2 += 1, x <<= 1;
-
-   /* Calculate the base logarithm from the top 8 bits as a 28-bit fractional
-    * value.
-    */
-   lg2 <<= 28;
-   lg2 += (png_8bit_l2[(x>>8)-128]+8) >> 4;
-
-   /* Now we need to interpolate the factor, this requires a division by the top
-    * 8 bits.  Do this with maximum precision.
-    */
-   x = ((x << 16) + (x >> 9)) / (x >> 8);
-
-   /* Since we divided by the top 8 bits of 'x' there will be a '1' at 1<<24,
-    * the value at 1<<16 (ignoring this) will be 0 or 1; this gives us exactly
-    * 16 bits to interpolate to get the low bits of the result.  Round the
-    * answer.  Note that the end point values are scaled by 64 to retain overall
-    * precision and that 'lg2' is current scaled by an extra 12 bits, so adjust
-    * the overall scaling by 6-12.  Round at every step.
-    */
-   x -= 1U << 24;
-
-   if (x <= 65536U) /* <= '257' */
-      lg2 += ((23591U * (65536U-x)) + (1U << (16+6-12-1))) >> (16+6-12);
-
-   else
-      lg2 -= ((23499U * (x-65536U)) + (1U << (16+6-12-1))) >> (16+6-12);
-
-   /* Safe, because the result can't have more than 20 bits: */
-   return (png_int_32)((lg2 + 2048) >> 12);
-}
-
-/* The 'exp()' case must invert the above, taking a 20-bit fixed point
- * logarithmic value and returning a 16 or 8-bit number as appropriate.  In
- * each case only the low 16 bits are relevant - the fraction - since the
- * integer bits (the top 4) simply determine a shift.
- *
- * The worst case is the 16-bit distinction between 65535 and 65534, this
- * requires perhaps spurious accuracy in the decoding of the logarithm to
- * distinguish log2(65535/65534.5) - 10^-5 or 17 bits.  There is little chance
- * of getting this accuracy in practice.
- *
- * To deal with this the following exp() function works out the exponent of the
- * frational part of the logarithm by using an accurate 32-bit value from the
- * top four fractional bits then multiplying in the remaining bits.
- */
-static png_uint_32
-png_32bit_exp[16] =
-{
-#  ifdef PNG_DO_BC
-      for (i=0;i<16;++i) { .5 + e(-i/16*l(2))*2^32; }
-#  else
-   /* NOTE: the first entry is deliberately set to the maximum 32-bit value. */
-   4294967295U, 4112874773U, 3938502376U, 3771522796U, 3611622603U, 3458501653U,
-   3311872529U, 3171459999U, 3037000500U, 2908241642U, 2784941738U, 2666869345U,
-   2553802834U, 2445529972U, 2341847524U, 2242560872U
-#  endif
-};
-
-/* Adjustment table; provided to explain the numbers in the code below. */
-#ifdef PNG_DO_BC
-for (i=11;i>=0;--i){ print i, " ", (1 - e(-(2^i)/65536*l(2))) * 2^(32-i), "\n"}
-   11 44937.64284865548751208448
-   10 45180.98734845585101160448
-    9 45303.31936980687359311872
-    8 45364.65110595323018870784
-    7 45395.35850361789624614912
-    6 45410.72259715102037508096
-    5 45418.40724413220722311168
-    4 45422.25021786898173001728
-    3 45424.17186732298419044352
-    2 45425.13273269940811464704
-    1 45425.61317555035558641664
-    0 45425.85339951654943850496
-#endif
-
-PNG_STATIC png_uint_32
-png_exp(png_fixed_point x)
-{
-   if (x > 0 && x <= 0xfffff) /* Else overflow or zero (underflow) */
-   {
-      /* Obtain a 4-bit approximation */
-      png_uint_32 e = png_32bit_exp[(x >> 12) & 0xf];
-
-      /* Incorporate the low 12 bits - these decrease the returned value by
-       * multiplying by a number less than 1 if the bit is set.  The multiplier
-       * is determined by the above table and the shift. Notice that the values
-       * converge on 45426 and this is used to allow linear interpolation of the
-       * low bits.
-       */
-      if (x & 0x800)
-         e -= (((e >> 16) * 44938U) +  16U) >> 5;
-
-      if (x & 0x400)
-         e -= (((e >> 16) * 45181U) +  32U) >> 6;
-
-      if (x & 0x200)
-         e -= (((e >> 16) * 45303U) +  64U) >> 7;
-
-      if (x & 0x100)
-         e -= (((e >> 16) * 45365U) + 128U) >> 8;
-
-      if (x & 0x080)
-         e -= (((e >> 16) * 45395U) + 256U) >> 9;
-
-      if (x & 0x040)
-         e -= (((e >> 16) * 45410U) + 512U) >> 10;
-
-      /* And handle the low 6 bits in a single block. */
-      e -= (((e >> 16) * 355U * (x & 0x3fU)) + 256U) >> 9;
-
-      /* Handle the upper bits of x. */
-      e >>= x >> 16;
-      return e;
-   }
-
-   /* Check for overflow */
-   if (x <= 0)
-      return png_32bit_exp[0];
-
-   /* Else underflow */
-   return 0;
-}
-
-PNG_STATIC png_byte
-png_exp8bit(png_fixed_point lg2)
-{
-   /* Get a 32-bit value: */
-   png_uint_32 x = png_exp(lg2);
-
-   /* Convert the 32-bit value to 0..255 by multiplying by 256-1, note that the
-    * second, rounding, step can't overflow because of the first, subtraction,
-    * step.
-    */
-   x -= x >> 8;
-   return (png_byte)((x + 0x7fffffU) >> 24);
-}
-
-PNG_STATIC png_uint_16
-png_exp16bit(png_fixed_point lg2)
-{
-   /* Get a 32-bit value: */
-   png_uint_32 x = png_exp(lg2);
-
-   /* Convert the 32-bit value to 0..65535 by multiplying by 65536-1: */
-   x -= x >> 16;
-   return (png_uint_16)((x + 32767U) >> 16);
-}
-#endif /* FLOATING_ARITHMETIC */
-
-png_byte
-png_gamma_8bit_correct(unsigned int value, png_fixed_point gamma_val)
-{
-   if (value > 0 && value < 255)
-   {
-#     ifdef PNG_FLOATING_ARITHMETIC_SUPPORTED
-         double r = floor(255*pow(value/255.,gamma_val*.00001)+.5);
-         return (png_byte)r;
-#     else
-         png_int_32 lg2 = png_log8bit(value);
-         png_fixed_point res;
-
-         if (png_muldiv(&res, gamma_val, lg2, PNG_FP_1))
-            return png_exp8bit(res);
-
-         /* Overflow. */
-         value = 0;
-#     endif
-   }
-
-   return (png_byte)value;
-}
-
-png_uint_16
-png_gamma_16bit_correct(unsigned int value, png_fixed_point gamma_val)
-{
-   if (value > 0 && value < 65535)
-   {
-#     ifdef PNG_FLOATING_ARITHMETIC_SUPPORTED
-         double r = floor(65535*pow(value/65535.,gamma_val*.00001)+.5);
-         return (png_uint_16)r;
-#     else
-         png_int_32 lg2 = png_log16bit(value);
-         png_fixed_point res;
-
-         if (png_muldiv(&res, gamma_val, lg2, PNG_FP_1))
-            return png_exp16bit(res);
-
-         /* Overflow. */
-         value = 0;
-#     endif
-   }
-
-   return (png_uint_16)value;
-}
-
-/* This does the right thing based on the bit_depth field of the
- * png_struct, interpreting values as 8-bit or 16-bit.  While the result
- * is nominally a 16-bit value if bit depth is 8 then the result is
- * 8-bit (as are the arguments.)
- */
-png_uint_16 /* PRIVATE */
-png_gamma_correct(png_structp png_ptr, unsigned int value,
-    png_fixed_point gamma_val)
-{
-   if (png_ptr->bit_depth == 8)
-      return png_gamma_8bit_correct(value, gamma_val);
-
-   else
-      return png_gamma_16bit_correct(value, gamma_val);
-}
-
-/* This is the shared test on whether a gamma value is 'significant' - whether
- * it is worth doing gamma correction.
- */
-int /* PRIVATE */
-png_gamma_significant(png_fixed_point gamma_val)
-{
-   return gamma_val < PNG_FP_1 - PNG_GAMMA_THRESHOLD_FIXED ||
-       gamma_val > PNG_FP_1 + PNG_GAMMA_THRESHOLD_FIXED;
-}
-
-/* Internal function to build a single 16-bit table - the table consists of
- * 'num' 256-entry subtables, where 'num' is determined by 'shift' - the amount
- * to shift the input values right (or 16-number_of_signifiant_bits).
- *
- * The caller is responsible for ensuring that the table gets cleaned up on
- * png_error (i.e. if one of the mallocs below fails) - i.e. the *table argument
- * should be somewhere that will be cleaned.
- */
-static void
-png_build_16bit_table(png_structp png_ptr, png_uint_16pp *ptable,
-   PNG_CONST unsigned int shift, PNG_CONST png_fixed_point gamma_val)
-{
-   /* Various values derived from 'shift': */
-   PNG_CONST unsigned int num = 1U << (8U - shift);
-   PNG_CONST unsigned int max = (1U << (16U - shift))-1U;
-   PNG_CONST unsigned int max_by_2 = 1U << (15U-shift);
-   unsigned int i;
-
-   png_uint_16pp table = *ptable =
-       (png_uint_16pp)png_calloc(png_ptr, num * png_sizeof(png_uint_16p));
-
-   for (i = 0; i < num; i++)
-   {
-      png_uint_16p sub_table = table[i] =
-          (png_uint_16p)png_malloc(png_ptr, 256 * png_sizeof(png_uint_16));
-
-      /* The 'threshold' test is repeated here because it can arise for one of
-       * the 16-bit tables even if the others don't hit it.
-       */
-      if (png_gamma_significant(gamma_val))
-      {
-         /* The old code would overflow at the end and this would cause the
-          * 'pow' function to return a result >1, resulting in an
-          * arithmetic error.  This code follows the spec exactly; ig is
-          * the recovered input sample, it always has 8-16 bits.
-          *
-          * We want input * 65535/max, rounded, the arithmetic fits in 32
-          * bits (unsigned) so long as max <= 32767.
-          */
-         unsigned int j;
-         for (j = 0; j < 256; j++)
-         {
-            png_uint_32 ig = (j << (8-shift)) + i;
-#           ifdef PNG_FLOATING_ARITHMETIC_SUPPORTED
-               /* Inline the 'max' scaling operation: */
-               double d = floor(65535*pow(ig/(double)max, gamma_val*.00001)+.5);
-               sub_table[j] = (png_uint_16)d;
-#           else
-               if (shift)
-                  ig = (ig * 65535U + max_by_2)/max;
-
-               sub_table[j] = png_gamma_16bit_correct(ig, gamma_val);
-#           endif
-         }
-      }
-      else
-      {
-         /* We must still build a table, but do it the fast way. */
-         unsigned int j;
-
-         for (j = 0; j < 256; j++)
-         {
-            png_uint_32 ig = (j << (8-shift)) + i;
-
-            if (shift)
-               ig = (ig * 65535U + max_by_2)/max;
-
-            sub_table[j] = (png_uint_16)ig;
-         }
-      }
-   }
-}
-
-/* NOTE: this function expects the *inverse* of the overall gamma transformation
- * required.
- */
-static void
-png_build_16to8_table(png_structp png_ptr, png_uint_16pp *ptable,
-   PNG_CONST unsigned int shift, PNG_CONST png_fixed_point gamma_val)
-{
-   PNG_CONST unsigned int num = 1U << (8U - shift);
-   PNG_CONST unsigned int max = (1U << (16U - shift))-1U;
-   unsigned int i;
-   png_uint_32 last;
-
-   png_uint_16pp table = *ptable =
-       (png_uint_16pp)png_calloc(png_ptr, num * png_sizeof(png_uint_16p));
-
-   /* 'num' is the number of tables and also the number of low bits of the
-    * input 16-bit value used to select a table.  Each table is itself indexed
-    * by the high 8 bits of the value.
-    */
-   for (i = 0; i < num; i++)
-      table[i] = (png_uint_16p)png_malloc(png_ptr,
-          256 * png_sizeof(png_uint_16));
-
-   /* 'gamma_val' is set to the reciprocal of the value calculated above, so
-    * pow(out,g) is an *input* value.  'last' is the last input value set.
-    *
-    * In the loop 'i' is used to find output values.  Since the output is
-    * 8-bit there are only 256 possible values.  The tables are set up to
-    * select the closest possible output value for each input by finding
-    * the input value at the boundary between each pair of output values
-    * and filling the table up to that boundary with the lower output
-    * value.
-    *
-    * The boundary values are 0.5,1.5..253.5,254.5.  Since these are 9-bit
-    * values the code below uses a 16-bit value in i; the values start at
-    * 128.5 (for 0.5) and step by 257, for a total of 254 values (the last
-    * entries are filled with 255).  Start i at 128 and fill all 'last'
-    * table entries <= 'max'
-    */
-   last = 0;
-   for (i = 0; i < 255; ++i) /* 8-bit output value */
-   {
-      /* Find the corresponding maximum input value */
-      png_uint_16 out = (png_uint_16)(i * 257U); /* 16-bit output value */
-
-      /* Find the boundary value in 16 bits: */
-      png_uint_32 bound = png_gamma_16bit_correct(out+128U, gamma_val);
-
-      /* Adjust (round) to (16-shift) bits: */
-      bound = (bound * max + 32768U)/65535U + 1U;
-
-      while (last < bound)
-      {
-         table[last & (0xffU >> shift)][last >> (8U - shift)] = out;
-         last++;
-      }
-   }
-
-   /* And fill in the final entries. */
-   while (last < (num << 8))
-   {
-      table[last & (0xff >> shift)][last >> (8U - shift)] = 65535U;
-      last++;
-   }
-}
-
-/* Build a single 8-bit table: same as the 16-bit case but much simpler (and
- * typically much faster).  Note that libpng currently does no sBIT processing
- * (apparently contrary to the spec) so a 256-entry table is always generated.
- */
-static void
-png_build_8bit_table(png_structp png_ptr, png_bytepp ptable,
-   PNG_CONST png_fixed_point gamma_val)
-{
-   unsigned int i;
-   png_bytep table = *ptable = (png_bytep)png_malloc(png_ptr, 256);
-
-   if (png_gamma_significant(gamma_val)) for (i=0; i<256; i++)
-      table[i] = png_gamma_8bit_correct(i, gamma_val);
-
-   else for (i=0; i<256; ++i)
-      table[i] = (png_byte)i;
-}
-
-/* Used from png_read_destroy and below to release the memory used by the gamma
- * tables.
- */
-void /* PRIVATE */
-png_destroy_gamma_table(png_structp png_ptr)
-{
-   png_free(png_ptr, png_ptr->gamma_table);
-   png_ptr->gamma_table = NULL;
-
-   if (png_ptr->gamma_16_table != NULL)
-   {
-      int i;
-      int istop = (1 << (8 - png_ptr->gamma_shift));
-      for (i = 0; i < istop; i++)
-      {
-         png_free(png_ptr, png_ptr->gamma_16_table[i]);
-      }
-   png_free(png_ptr, png_ptr->gamma_16_table);
-   png_ptr->gamma_16_table = NULL;
-   }
-
-#if defined(PNG_READ_BACKGROUND_SUPPORTED) || \
-   defined(PNG_READ_ALPHA_MODE_SUPPORTED) || \
-   defined(PNG_READ_RGB_TO_GRAY_SUPPORTED)
-   png_free(png_ptr, png_ptr->gamma_from_1);
-   png_ptr->gamma_from_1 = NULL;
-   png_free(png_ptr, png_ptr->gamma_to_1);
-   png_ptr->gamma_to_1 = NULL;
-
-   if (png_ptr->gamma_16_from_1 != NULL)
-   {
-      int i;
-      int istop = (1 << (8 - png_ptr->gamma_shift));
-      for (i = 0; i < istop; i++)
-      {
-         png_free(png_ptr, png_ptr->gamma_16_from_1[i]);
-      }
-   png_free(png_ptr, png_ptr->gamma_16_from_1);
-   png_ptr->gamma_16_from_1 = NULL;
-   }
-   if (png_ptr->gamma_16_to_1 != NULL)
-   {
-      int i;
-      int istop = (1 << (8 - png_ptr->gamma_shift));
-      for (i = 0; i < istop; i++)
-      {
-         png_free(png_ptr, png_ptr->gamma_16_to_1[i]);
-      }
-   png_free(png_ptr, png_ptr->gamma_16_to_1);
-   png_ptr->gamma_16_to_1 = NULL;
-   }
-#endif /* READ_BACKGROUND || READ_ALPHA_MODE || RGB_TO_GRAY */
-}
-
-/* We build the 8- or 16-bit gamma tables here.  Note that for 16-bit
- * tables, we don't make a full table if we are reducing to 8-bit in
- * the future.  Note also how the gamma_16 tables are segmented so that
- * we don't need to allocate > 64K chunks for a full 16-bit table.
- */
-void /* PRIVATE */
-png_build_gamma_table(png_structp png_ptr, int bit_depth)
-{
-  png_debug(1, "in png_build_gamma_table");
-
-  /* Remove any existing table; this copes with multiple calls to
-   * png_read_update_info.  The warning is because building the gamma tables
-   * multiple times is a performance hit - it's harmless but the ability to call
-   * png_read_update_info() multiple times is new in 1.5.6 so it seems sensible
-   * to warn if the app introduces such a hit.
-   */
-  if (png_ptr->gamma_table != NULL || png_ptr->gamma_16_table != NULL)
-  {
-    png_warning(png_ptr, "gamma table being rebuilt");
-    png_destroy_gamma_table(png_ptr);
-  }
-
-  if (bit_depth <= 8)
-  {
-     png_build_8bit_table(png_ptr, &png_ptr->gamma_table,
-         png_ptr->screen_gamma > 0 ?  png_reciprocal2(png_ptr->gamma,
-         png_ptr->screen_gamma) : PNG_FP_1);
-
-#if defined(PNG_READ_BACKGROUND_SUPPORTED) || \
-   defined(PNG_READ_ALPHA_MODE_SUPPORTED) || \
-   defined(PNG_READ_RGB_TO_GRAY_SUPPORTED)
-     if (png_ptr->transformations & (PNG_COMPOSE | PNG_RGB_TO_GRAY))
-     {
-        png_build_8bit_table(png_ptr, &png_ptr->gamma_to_1,
-            png_reciprocal(png_ptr->gamma));
-
-        png_build_8bit_table(png_ptr, &png_ptr->gamma_from_1,
-            png_ptr->screen_gamma > 0 ?  png_reciprocal(png_ptr->screen_gamma) :
-            png_ptr->gamma/* Probably doing rgb_to_gray */);
-     }
-#endif /* READ_BACKGROUND || READ_ALPHA_MODE || RGB_TO_GRAY */
-  }
-  else
-  {
-     png_byte shift, sig_bit;
-
-     if (png_ptr->color_type & PNG_COLOR_MASK_COLOR)
-     {
-        sig_bit = png_ptr->sig_bit.red;
-
-        if (png_ptr->sig_bit.green > sig_bit)
-           sig_bit = png_ptr->sig_bit.green;
-
-        if (png_ptr->sig_bit.blue > sig_bit)
-           sig_bit = png_ptr->sig_bit.blue;
-     }
-     else
-        sig_bit = png_ptr->sig_bit.gray;
-
-     /* 16-bit gamma code uses this equation:
-      *
-      *   ov = table[(iv & 0xff) >> gamma_shift][iv >> 8]
-      *
-      * Where 'iv' is the input color value and 'ov' is the output value -
-      * pow(iv, gamma).
-      *
-      * Thus the gamma table consists of up to 256 256-entry tables.  The table
-      * is selected by the (8-gamma_shift) most significant of the low 8 bits of
-      * the color value then indexed by the upper 8 bits:
-      *
-      *   table[low bits][high 8 bits]
-      *
-      * So the table 'n' corresponds to all those 'iv' of:
-      *
-      *   <all high 8-bit values><n << gamma_shift>..<(n+1 << gamma_shift)-1>
-      *
-      */
-     if (sig_bit > 0 && sig_bit < 16U)
-        shift = (png_byte)(16U - sig_bit); /* shift == insignificant bits */
-
-     else
-        shift = 0; /* keep all 16 bits */
-
-     if (png_ptr->transformations & (PNG_16_TO_8 | PNG_SCALE_16_TO_8))
-     {
-        /* PNG_MAX_GAMMA_8 is the number of bits to keep - effectively
-         * the significant bits in the *input* when the output will
-         * eventually be 8 bits.  By default it is 11.
-         */
-        if (shift < (16U - PNG_MAX_GAMMA_8))
-           shift = (16U - PNG_MAX_GAMMA_8);
-     }
-
-     if (shift > 8U)
-        shift = 8U; /* Guarantees at least one table! */
-
-     png_ptr->gamma_shift = shift;
-
-#ifdef PNG_16BIT_SUPPORTED
-     /* NOTE: prior to 1.5.4 this test used to include PNG_BACKGROUND (now
-      * PNG_COMPOSE).  This effectively smashed the background calculation for
-      * 16-bit output because the 8-bit table assumes the result will be reduced
-      * to 8 bits.
-      */
-     if (png_ptr->transformations & (PNG_16_TO_8 | PNG_SCALE_16_TO_8))
-#endif
-         png_build_16to8_table(png_ptr, &png_ptr->gamma_16_table, shift,
-         png_ptr->screen_gamma > 0 ? png_product2(png_ptr->gamma,
-         png_ptr->screen_gamma) : PNG_FP_1);
-
-#ifdef PNG_16BIT_SUPPORTED
-     else
-         png_build_16bit_table(png_ptr, &png_ptr->gamma_16_table, shift,
-         png_ptr->screen_gamma > 0 ? png_reciprocal2(png_ptr->gamma,
-         png_ptr->screen_gamma) : PNG_FP_1);
-#endif
-
-#if defined(PNG_READ_BACKGROUND_SUPPORTED) || \
-   defined(PNG_READ_ALPHA_MODE_SUPPORTED) || \
-   defined(PNG_READ_RGB_TO_GRAY_SUPPORTED)
-     if (png_ptr->transformations & (PNG_COMPOSE | PNG_RGB_TO_GRAY))
-     {
-        png_build_16bit_table(png_ptr, &png_ptr->gamma_16_to_1, shift,
-            png_reciprocal(png_ptr->gamma));
-
-        /* Notice that the '16 from 1' table should be full precision, however
-         * the lookup on this table still uses gamma_shift, so it can't be.
-         * TODO: fix this.
-         */
-        png_build_16bit_table(png_ptr, &png_ptr->gamma_16_from_1, shift,
-            png_ptr->screen_gamma > 0 ? png_reciprocal(png_ptr->screen_gamma) :
-            png_ptr->gamma/* Probably doing rgb_to_gray */);
-     }
-#endif /* READ_BACKGROUND || READ_ALPHA_MODE || RGB_TO_GRAY */
-  }
-}
-#endif /* READ_GAMMA */
-#endif /* defined(PNG_READ_SUPPORTED) || defined(PNG_WRITE_SUPPORTED) */
diff --git a/plugingui/png/png.h b/plugingui/png/png.h
deleted file mode 100644
index 5b95fe8..0000000
--- a/plugingui/png/png.h
+++ /dev/null
@@ -1,2674 +0,0 @@
-
-/* png.h - header file for PNG reference library
- *
- * libpng version 1.5.13 - September 27, 2012
- * Copyright (c) 1998-2012 Glenn Randers-Pehrson
- * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
- * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)
- *
- * This code is released under the libpng license (See LICENSE, below)
- *
- * Authors and maintainers:
- *   libpng versions 0.71, May 1995, through 0.88, January 1996: Guy Schalnat
- *   libpng versions 0.89c, June 1996, through 0.96, May 1997: Andreas Dilger
- *   libpng versions 0.97, January 1998, through 1.5.13 - September 27, 2012: Glenn
- *   See also "Contributing Authors", below.
- *
- * Note about libpng version numbers:
- *
- *   Due to various miscommunications, unforeseen code incompatibilities
- *   and occasional factors outside the authors' control, version numbering
- *   on the library has not always been consistent and straightforward.
- *   The following table summarizes matters since version 0.89c, which was
- *   the first widely used release:
- *
- *    source                 png.h  png.h  shared-lib
- *    version                string   int  version
- *    -------                ------ -----  ----------
- *    0.89c "1.0 beta 3"     0.89      89  1.0.89
- *    0.90  "1.0 beta 4"     0.90      90  0.90  [should have been 2.0.90]
- *    0.95  "1.0 beta 5"     0.95      95  0.95  [should have been 2.0.95]
- *    0.96  "1.0 beta 6"     0.96      96  0.96  [should have been 2.0.96]
- *    0.97b "1.00.97 beta 7" 1.00.97   97  1.0.1 [should have been 2.0.97]
- *    0.97c                  0.97      97  2.0.97
- *    0.98                   0.98      98  2.0.98
- *    0.99                   0.99      98  2.0.99
- *    0.99a-m                0.99      99  2.0.99
- *    1.00                   1.00     100  2.1.0 [100 should be 10000]
- *    1.0.0      (from here on, the   100  2.1.0 [100 should be 10000]
- *    1.0.1       png.h string is   10001  2.1.0
- *    1.0.1a-e    identical to the  10002  from here on, the shared library
- *    1.0.2       source version)   10002  is 2.V where V is the source code
- *    1.0.2a-b                      10003  version, except as noted.
- *    1.0.3                         10003
- *    1.0.3a-d                      10004
- *    1.0.4                         10004
- *    1.0.4a-f                      10005
- *    1.0.5 (+ 2 patches)           10005
- *    1.0.5a-d                      10006
- *    1.0.5e-r                      10100 (not source compatible)
- *    1.0.5s-v                      10006 (not binary compatible)
- *    1.0.6 (+ 3 patches)           10006 (still binary incompatible)
- *    1.0.6d-f                      10007 (still binary incompatible)
- *    1.0.6g                        10007
- *    1.0.6h                        10007  10.6h (testing xy.z so-numbering)
- *    1.0.6i                        10007  10.6i
- *    1.0.6j                        10007  2.1.0.6j (incompatible with 1.0.0)
- *    1.0.7beta11-14        DLLNUM  10007  2.1.0.7beta11-14 (binary compatible)
- *    1.0.7beta15-18           1    10007  2.1.0.7beta15-18 (binary compatible)
- *    1.0.7rc1-2               1    10007  2.1.0.7rc1-2 (binary compatible)
- *    1.0.7                    1    10007  (still compatible)
- *    1.0.8beta1-4             1    10008  2.1.0.8beta1-4
- *    1.0.8rc1                 1    10008  2.1.0.8rc1
- *    1.0.8                    1    10008  2.1.0.8
- *    1.0.9beta1-6             1    10009  2.1.0.9beta1-6
- *    1.0.9rc1                 1    10009  2.1.0.9rc1
- *    1.0.9beta7-10            1    10009  2.1.0.9beta7-10
- *    1.0.9rc2                 1    10009  2.1.0.9rc2
- *    1.0.9                    1    10009  2.1.0.9
- *    1.0.10beta1              1    10010  2.1.0.10beta1
- *    1.0.10rc1                1    10010  2.1.0.10rc1
- *    1.0.10                   1    10010  2.1.0.10
- *    1.0.11beta1-3            1    10011  2.1.0.11beta1-3
- *    1.0.11rc1                1    10011  2.1.0.11rc1
- *    1.0.11                   1    10011  2.1.0.11
- *    1.0.12beta1-2            2    10012  2.1.0.12beta1-2
- *    1.0.12rc1                2    10012  2.1.0.12rc1
- *    1.0.12                   2    10012  2.1.0.12
- *    1.1.0a-f                 -    10100  2.1.1.0a-f (branch abandoned)
- *    1.2.0beta1-2             2    10200  2.1.2.0beta1-2
- *    1.2.0beta3-5             3    10200  3.1.2.0beta3-5
- *    1.2.0rc1                 3    10200  3.1.2.0rc1
- *    1.2.0                    3    10200  3.1.2.0
- *    1.2.1beta1-4             3    10201  3.1.2.1beta1-4
- *    1.2.1rc1-2               3    10201  3.1.2.1rc1-2
- *    1.2.1                    3    10201  3.1.2.1
- *    1.2.2beta1-6            12    10202  12.so.0.1.2.2beta1-6
- *    1.0.13beta1             10    10013  10.so.0.1.0.13beta1
- *    1.0.13rc1               10    10013  10.so.0.1.0.13rc1
- *    1.2.2rc1                12    10202  12.so.0.1.2.2rc1
- *    1.0.13                  10    10013  10.so.0.1.0.13
- *    1.2.2                   12    10202  12.so.0.1.2.2
- *    1.2.3rc1-6              12    10203  12.so.0.1.2.3rc1-6
- *    1.2.3                   12    10203  12.so.0.1.2.3
- *    1.2.4beta1-3            13    10204  12.so.0.1.2.4beta1-3
- *    1.0.14rc1               13    10014  10.so.0.1.0.14rc1
- *    1.2.4rc1                13    10204  12.so.0.1.2.4rc1
- *    1.0.14                  10    10014  10.so.0.1.0.14
- *    1.2.4                   13    10204  12.so.0.1.2.4
- *    1.2.5beta1-2            13    10205  12.so.0.1.2.5beta1-2
- *    1.0.15rc1-3             10    10015  10.so.0.1.0.15rc1-3
- *    1.2.5rc1-3              13    10205  12.so.0.1.2.5rc1-3
- *    1.0.15                  10    10015  10.so.0.1.0.15
- *    1.2.5                   13    10205  12.so.0.1.2.5
- *    1.2.6beta1-4            13    10206  12.so.0.1.2.6beta1-4
- *    1.0.16                  10    10016  10.so.0.1.0.16
- *    1.2.6                   13    10206  12.so.0.1.2.6
- *    1.2.7beta1-2            13    10207  12.so.0.1.2.7beta1-2
- *    1.0.17rc1               10    10017  12.so.0.1.0.17rc1
- *    1.2.7rc1                13    10207  12.so.0.1.2.7rc1
- *    1.0.17                  10    10017  12.so.0.1.0.17
- *    1.2.7                   13    10207  12.so.0.1.2.7
- *    1.2.8beta1-5            13    10208  12.so.0.1.2.8beta1-5
- *    1.0.18rc1-5             10    10018  12.so.0.1.0.18rc1-5
- *    1.2.8rc1-5              13    10208  12.so.0.1.2.8rc1-5
- *    1.0.18                  10    10018  12.so.0.1.0.18
- *    1.2.8                   13    10208  12.so.0.1.2.8
- *    1.2.9beta1-3            13    10209  12.so.0.1.2.9beta1-3
- *    1.2.9beta4-11           13    10209  12.so.0.9[.0]
- *    1.2.9rc1                13    10209  12.so.0.9[.0]
- *    1.2.9                   13    10209  12.so.0.9[.0]
- *    1.2.10beta1-7           13    10210  12.so.0.10[.0]
- *    1.2.10rc1-2             13    10210  12.so.0.10[.0]
- *    1.2.10                  13    10210  12.so.0.10[.0]
- *    1.4.0beta1-5            14    10400  14.so.0.0[.0]
- *    1.2.11beta1-4           13    10211  12.so.0.11[.0]
- *    1.4.0beta7-8            14    10400  14.so.0.0[.0]
- *    1.2.11                  13    10211  12.so.0.11[.0]
- *    1.2.12                  13    10212  12.so.0.12[.0]
- *    1.4.0beta9-14           14    10400  14.so.0.0[.0]
- *    1.2.13                  13    10213  12.so.0.13[.0]
- *    1.4.0beta15-36          14    10400  14.so.0.0[.0]
- *    1.4.0beta37-87          14    10400  14.so.14.0[.0]
- *    1.4.0rc01               14    10400  14.so.14.0[.0]
- *    1.4.0beta88-109         14    10400  14.so.14.0[.0]
- *    1.4.0rc02-08            14    10400  14.so.14.0[.0]
- *    1.4.0                   14    10400  14.so.14.0[.0]
- *    1.4.1beta01-03          14    10401  14.so.14.1[.0]
- *    1.4.1rc01               14    10401  14.so.14.1[.0]
- *    1.4.1beta04-12          14    10401  14.so.14.1[.0]
- *    1.4.1                   14    10401  14.so.14.1[.0]
- *    1.4.2                   14    10402  14.so.14.2[.0]
- *    1.4.3                   14    10403  14.so.14.3[.0]
- *    1.4.4                   14    10404  14.so.14.4[.0]
- *    1.5.0beta01-58          15    10500  15.so.15.0[.0]
- *    1.5.0rc01-07            15    10500  15.so.15.0[.0]
- *    1.5.0                   15    10500  15.so.15.0[.0]
- *    1.5.1beta01-11          15    10501  15.so.15.1[.0]
- *    1.5.1rc01-02            15    10501  15.so.15.1[.0]
- *    1.5.1                   15    10501  15.so.15.1[.0]
- *    1.5.2beta01-03          15    10502  15.so.15.2[.0]
- *    1.5.2rc01-03            15    10502  15.so.15.2[.0]
- *    1.5.2                   15    10502  15.so.15.2[.0]
- *    1.5.3beta01-10          15    10503  15.so.15.3[.0]
- *    1.5.3rc01-02            15    10503  15.so.15.3[.0]
- *    1.5.3beta11             15    10503  15.so.15.3[.0]
- *    1.5.3 [omitted]
- *    1.5.4beta01-08          15    10504  15.so.15.4[.0]
- *    1.5.4rc01               15    10504  15.so.15.4[.0]
- *    1.5.4                   15    10504  15.so.15.4[.0]
- *    1.5.5beta01-08          15    10505  15.so.15.5[.0]
- *    1.5.5rc01               15    10505  15.so.15.5[.0]
- *    1.5.5                   15    10505  15.so.15.5[.0]
- *    1.5.6beta01-07          15    10506  15.so.15.6[.0]
- *    1.5.6rc01-03            15    10506  15.so.15.6[.0]
- *    1.5.6                   15    10506  15.so.15.6[.0]
- *    1.5.7beta01-05          15    10507  15.so.15.7[.0]
- *    1.5.7rc01-03            15    10507  15.so.15.7[.0]
- *    1.5.7                   15    10507  15.so.15.7[.0]
- *    1.5.8beta01             15    10508  15.so.15.8[.0]
- *    1.5.8rc01               15    10508  15.so.15.8[.0]
- *    1.5.8                   15    10508  15.so.15.8[.0]
- *    1.5.9beta01-02          15    10509  15.so.15.9[.0]
- *    1.5.9rc01               15    10509  15.so.15.9[.0]
- *    1.5.9                   15    10509  15.so.15.9[.0]
- *    1.5.10beta01-05         15    10510  15.so.15.10[.0]
- *    1.5.10                  15    10510  15.so.15.10[.0]
- *    1.5.11beta01            15    10511  15.so.15.11[.0]
- *    1.5.11rc01-05           15    10511  15.so.15.11[.0]
- *    1.5.11                  15    10511  15.so.15.11[.0]
- *    1.5.12                  15    10512  15.so.15.12[.0]
- *    1.5.13beta01-02         15    10513  15.so.15.13[.0]
- *    1.5.13rc01              15    10513  15.so.15.13[.0]
- *    1.5.13                  15    10513  15.so.15.13[.0]
- *
- *   Henceforth the source version will match the shared-library major
- *   and minor numbers; the shared-library major version number will be
- *   used for changes in backward compatibility, as it is intended.  The
- *   PNG_LIBPNG_VER macro, which is not used within libpng but is available
- *   for applications, is an unsigned integer of the form xyyzz corresponding
- *   to the source version x.y.z (leading zeros in y and z).  Beta versions
- *   were given the previous public release number plus a letter, until
- *   version 1.0.6j; from then on they were given the upcoming public
- *   release number plus "betaNN" or "rcNN".
- *
- *   Binary incompatibility exists only when applications make direct access
- *   to the info_ptr or png_ptr members through png.h, and the compiled
- *   application is loaded with a different version of the library.
- *
- *   DLLNUM will change each time there are forward or backward changes
- *   in binary compatibility (e.g., when a new feature is added).
- *
- * See libpng-manual.txt or libpng.3 for more information.  The PNG
- * specification is available as a W3C Recommendation and as an ISO
- * Specification, <http://www.w3.org/TR/2003/REC-PNG-20031110/
- */
-
-/*
- * COPYRIGHT NOTICE, DISCLAIMER, and LICENSE:
- *
- * If you modify libpng you may insert additional notices immediately following
- * this sentence.
- *
- * This code is released under the libpng license.
- *
- * libpng versions 1.2.6, August 15, 2004, through 1.5.13, September 27, 2012, are
- * Copyright (c) 2004, 2006-2012 Glenn Randers-Pehrson, and are
- * distributed according to the same disclaimer and license as libpng-1.2.5
- * with the following individual added to the list of Contributing Authors:
- *
- *    Cosmin Truta
- *
- * libpng versions 1.0.7, July 1, 2000, through 1.2.5, October 3, 2002, are
- * Copyright (c) 2000-2002 Glenn Randers-Pehrson, and are
- * distributed according to the same disclaimer and license as libpng-1.0.6
- * with the following individuals added to the list of Contributing Authors:
- *
- *    Simon-Pierre Cadieux
- *    Eric S. Raymond
- *    Gilles Vollant
- *
- * and with the following additions to the disclaimer:
- *
- *    There is no warranty against interference with your enjoyment of the
- *    library or against infringement.  There is no warranty that our
- *    efforts or the library will fulfill any of your particular purposes
- *    or needs.  This library is provided with all faults, and the entire
- *    risk of satisfactory quality, performance, accuracy, and effort is with
- *    the user.
- *
- * libpng versions 0.97, January 1998, through 1.0.6, March 20, 2000, are
- * Copyright (c) 1998, 1999, 2000 Glenn Randers-Pehrson, and are
- * distributed according to the same disclaimer and license as libpng-0.96,
- * with the following individuals added to the list of Contributing Authors:
- *
- *    Tom Lane
- *    Glenn Randers-Pehrson
- *    Willem van Schaik
- *
- * libpng versions 0.89, June 1996, through 0.96, May 1997, are
- * Copyright (c) 1996, 1997 Andreas Dilger
- * Distributed according to the same disclaimer and license as libpng-0.88,
- * with the following individuals added to the list of Contributing Authors:
- *
- *    John Bowler
- *    Kevin Bracey
- *    Sam Bushell
- *    Magnus Holmgren
- *    Greg Roelofs
- *    Tom Tanner
- *
- * libpng versions 0.5, May 1995, through 0.88, January 1996, are
- * Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.
- *
- * For the purposes of this copyright and license, "Contributing Authors"
- * is defined as the following set of individuals:
- *
- *    Andreas Dilger
- *    Dave Martindale
- *    Guy Eric Schalnat
- *    Paul Schmidt
- *    Tim Wegner
- *
- * The PNG Reference Library is supplied "AS IS".  The Contributing Authors
- * and Group 42, Inc. disclaim all warranties, expressed or implied,
- * including, without limitation, the warranties of merchantability and of
- * fitness for any purpose.  The Contributing Authors and Group 42, Inc.
- * assume no liability for direct, indirect, incidental, special, exemplary,
- * or consequential damages, which may result from the use of the PNG
- * Reference Library, even if advised of the possibility of such damage.
- *
- * Permission is hereby granted to use, copy, modify, and distribute this
- * source code, or portions hereof, for any purpose, without fee, subject
- * to the following restrictions:
- *
- *   1. The origin of this source code must not be misrepresented.
- *
- *   2. Altered versions must be plainly marked as such and must not
- *      be misrepresented as being the original source.
- *
- *   3. This Copyright notice may not be removed or altered from
- *      any source or altered source distribution.
- *
- * The Contributing Authors and Group 42, Inc. specifically permit, without
- * fee, and encourage the use of this source code as a component to
- * supporting the PNG file format in commercial products.  If you use this
- * source code in a product, acknowledgment is not required but would be
- * appreciated.
- */
-
-/*
- * A "png_get_copyright" function is available, for convenient use in "about"
- * boxes and the like:
- *
- *     printf("%s", png_get_copyright(NULL));
- *
- * Also, the PNG logo (in PNG format, of course) is supplied in the
- * files "pngbar.png" and "pngbar.jpg (88x31) and "pngnow.png" (98x31).
- */
-
-/*
- * Libpng is OSI Certified Open Source Software.  OSI Certified is a
- * certification mark of the Open Source Initiative.
- */
-
-/*
- * The contributing authors would like to thank all those who helped
- * with testing, bug fixes, and patience.  This wouldn't have been
- * possible without all of you.
- *
- * Thanks to Frank J. T. Wojcik for helping with the documentation.
- */
-
-/*
- * Y2K compliance in libpng:
- * =========================
- *
- *    September 27, 2012
- *
- *    Since the PNG Development group is an ad-hoc body, we can't make
- *    an official declaration.
- *
- *    This is your unofficial assurance that libpng from version 0.71 and
- *    upward through 1.5.13 are Y2K compliant.  It is my belief that
- *    earlier versions were also Y2K compliant.
- *
- *    Libpng only has two year fields.  One is a 2-byte unsigned integer
- *    that will hold years up to 65535.  The other holds the date in text
- *    format, and will hold years up to 9999.
- *
- *    The integer is
- *        "png_uint_16 year" in png_time_struct.
- *
- *    The string is
- *        "char time_buffer[29]" in png_struct.  This will be no
- *    longer used in libpng-1.6.0 and will be removed from libpng-1.7.0.
- *
- *    There are seven time-related functions:
- *        png.c: png_convert_to_rfc_1123() in png.c
- *          (formerly png_convert_to_rfc_1152() in error)
- *        png_convert_from_struct_tm() in pngwrite.c, called in pngwrite.c
- *        png_convert_from_time_t() in pngwrite.c
- *        png_get_tIME() in pngget.c
- *        png_handle_tIME() in pngrutil.c, called in pngread.c
- *        png_set_tIME() in pngset.c
- *        png_write_tIME() in pngwutil.c, called in pngwrite.c
- *
- *    All handle dates properly in a Y2K environment.  The
- *    png_convert_from_time_t() function calls gmtime() to convert from system
- *    clock time, which returns (year - 1900), which we properly convert to
- *    the full 4-digit year.  There is a possibility that applications using
- *    libpng are not passing 4-digit years into the png_convert_to_rfc_1123()
- *    function, or that they are incorrectly passing only a 2-digit year
- *    instead of "year - 1900" into the png_convert_from_struct_tm() function,
- *    but this is not under our control.  The libpng documentation has always
- *    stated that it works with 4-digit years, and the APIs have been
- *    documented as such.
- *
- *    The tIME chunk itself is also Y2K compliant.  It uses a 2-byte unsigned
- *    integer to hold the year, and can hold years as large as 65535.
- *
- *    zlib, upon which libpng depends, is also Y2K compliant.  It contains
- *    no date-related code.
- *
- *       Glenn Randers-Pehrson
- *       libpng maintainer
- *       PNG Development Group
- */
-
-#ifndef PNG_H
-#define PNG_H
-
-/* This is not the place to learn how to use libpng. The file libpng-manual.txt
- * describes how to use libpng, and the file example.c summarizes it
- * with some code on which to build.  This file is useful for looking
- * at the actual function definitions and structure components.
- *
- * If you just need to read a PNG file and don't want to read the documentation
- * skip to the end of this file and read the section entitled 'simplified API'.
- */
-
-/* Version information for png.h - this should match the version in png.c */
-#define PNG_LIBPNG_VER_STRING "1.5.13"
-#define PNG_HEADER_VERSION_STRING \
-     " libpng version 1.5.13 - September 27, 2012\n"
-
-#define PNG_LIBPNG_VER_SONUM   15
-#define PNG_LIBPNG_VER_DLLNUM  15
-
-/* These should match the first 3 components of PNG_LIBPNG_VER_STRING: */
-#define PNG_LIBPNG_VER_MAJOR   1
-#define PNG_LIBPNG_VER_MINOR   5
-#define PNG_LIBPNG_VER_RELEASE 13
-
-/* This should match the numeric part of the final component of
- * PNG_LIBPNG_VER_STRING, omitting any leading zero:
- */
-
-#define PNG_LIBPNG_VER_BUILD  0
-
-/* Release Status */
-#define PNG_LIBPNG_BUILD_ALPHA    1
-#define PNG_LIBPNG_BUILD_BETA     2
-#define PNG_LIBPNG_BUILD_RC       3
-#define PNG_LIBPNG_BUILD_STABLE   4
-#define PNG_LIBPNG_BUILD_RELEASE_STATUS_MASK 7
-
-/* Release-Specific Flags */
-#define PNG_LIBPNG_BUILD_PATCH    8 /* Can be OR'ed with
-                                       PNG_LIBPNG_BUILD_STABLE only */
-#define PNG_LIBPNG_BUILD_PRIVATE 16 /* Cannot be OR'ed with
-                                       PNG_LIBPNG_BUILD_SPECIAL */
-#define PNG_LIBPNG_BUILD_SPECIAL 32 /* Cannot be OR'ed with
-                                       PNG_LIBPNG_BUILD_PRIVATE */
-
-#define PNG_LIBPNG_BUILD_BASE_TYPE PNG_LIBPNG_BUILD_STABLE
-
-/* Careful here.  At one time, Guy wanted to use 082, but that would be octal.
- * We must not include leading zeros.
- * Versions 0.7 through 1.0.0 were in the range 0 to 100 here (only
- * version 1.0.0 was mis-numbered 100 instead of 10000).  From
- * version 1.0.1 it's    xxyyzz, where x=major, y=minor, z=release
- */
-#define PNG_LIBPNG_VER 10513 /* 1.5.13 */
-
-/* Library configuration: these options cannot be changed after
- * the library has been built.
- */
-#ifndef PNGLCONF_H
-    /* If pnglibconf.h is missing, you can
-     * copy scripts/pnglibconf.h.prebuilt to pnglibconf.h
-     */
-#   include "pnglibconf.h"
-#endif
-
-#ifndef PNG_VERSION_INFO_ONLY
-#  ifndef PNG_BUILDING_SYMBOL_TABLE
-  /*
-   *   Standard header files (not needed for the version info or while
-   *   building symbol table -- see scripts/pnglibconf.dfa)
-   */
-#    ifdef PNG_SETJMP_SUPPORTED
-#      include <setjmp.h>
-#    endif
-
-    /* Need the time information for converting tIME chunks, it
-     * defines struct tm:
-     */
-#    ifdef PNG_CONVERT_tIME_SUPPORTED
-       /* "time.h" functions are not supported on all operating systems */
-#      include <time.h>
-#    endif
-#  endif
-
-/* Machine specific configuration. */
-#  include "pngconf.h"
-#endif
-
-/*
- * Added at libpng-1.2.8
- *
- * Ref MSDN: Private as priority over Special
- * VS_FF_PRIVATEBUILD File *was not* built using standard release
- * procedures. If this value is given, the StringFileInfo block must
- * contain a PrivateBuild string.
- *
- * VS_FF_SPECIALBUILD File *was* built by the original company using
- * standard release procedures but is a variation of the standard
- * file of the same version number. If this value is given, the
- * StringFileInfo block must contain a SpecialBuild string.
- */
-
-#ifdef PNG_USER_PRIVATEBUILD /* From pnglibconf.h */
-#  define PNG_LIBPNG_BUILD_TYPE \
-       (PNG_LIBPNG_BUILD_BASE_TYPE | PNG_LIBPNG_BUILD_PRIVATE)
-#else
-#  ifdef PNG_LIBPNG_SPECIALBUILD
-#    define PNG_LIBPNG_BUILD_TYPE \
-         (PNG_LIBPNG_BUILD_BASE_TYPE | PNG_LIBPNG_BUILD_SPECIAL)
-#  else
-#    define PNG_LIBPNG_BUILD_TYPE (PNG_LIBPNG_BUILD_BASE_TYPE)
-#  endif
-#endif
-
-#ifndef PNG_VERSION_INFO_ONLY
-
-/* Inhibit C++ name-mangling for libpng functions but not for system calls. */
-#ifdef __cplusplus
-extern "C" {
-#endif /* __cplusplus */
-
-/* Version information for C files, stored in png.c.  This had better match
- * the version above.
- */
-#define png_libpng_ver png_get_header_ver(NULL)
-
-/* This file is arranged in several sections:
- *
- * 1. Any configuration options that can be specified by for the application
- *    code when it is built.  (Build time configuration is in pnglibconf.h)
- * 2. Type definitions (base types are defined in pngconf.h), structure
- *    definitions.
- * 3. Exported library functions.
- *
- * The library source code has additional files (principally pngpriv.h) that
- * allow configuration of the library.
- */
-/* Section 1: run time configuration
- * See pnglibconf.h for build time configuration
- *
- * Run time configuration allows the application to choose between
- * implementations of certain arithmetic APIs.  The default is set
- * at build time and recorded in pnglibconf.h, but it is safe to
- * override these (and only these) settings.  Note that this won't
- * change what the library does, only application code, and the
- * settings can (and probably should) be made on a per-file basis
- * by setting the #defines before including png.h
- *
- * Use macros to read integers from PNG data or use the exported
- * functions?
- *   PNG_USE_READ_MACROS: use the macros (see below)  Note that
- *     the macros evaluate their argument multiple times.
- *   PNG_NO_USE_READ_MACROS: call the relevant library function.
- *
- * Use the alternative algorithm for compositing alpha samples that
- * does not use division?
- *   PNG_READ_COMPOSITE_NODIV_SUPPORTED: use the 'no division'
- *      algorithm.
- *   PNG_NO_READ_COMPOSITE_NODIV: use the 'division' algorithm.
- *
- * How to handle benign errors if PNG_ALLOW_BENIGN_ERRORS is
- * false?
- *   PNG_ALLOW_BENIGN_ERRORS: map calls to the benign error
- *      APIs to png_warning.
- * Otherwise the calls are mapped to png_error.
- */
-
-/* Section 2: type definitions, including structures and compile time
- * constants.
- * See pngconf.h for base types that vary by machine/system
- */
-
-/* This triggers a compiler error in png.c, if png.c and png.h
- * do not agree upon the version number.
- */
-typedef char* png_libpng_version_1_5_13;
-
-/* Three color definitions.  The order of the red, green, and blue, (and the
- * exact size) is not important, although the size of the fields need to
- * be png_byte or png_uint_16 (as defined below).
- */
-typedef struct png_color_struct
-{
-   png_byte red;
-   png_byte green;
-   png_byte blue;
-} png_color;
-typedef png_color FAR * png_colorp;
-typedef PNG_CONST png_color FAR * png_const_colorp;
-typedef png_color FAR * FAR * png_colorpp;
-
-typedef struct png_color_16_struct
-{
-   png_byte index;    /* used for palette files */
-   png_uint_16 red;   /* for use in red green blue files */
-   png_uint_16 green;
-   png_uint_16 blue;
-   png_uint_16 gray;  /* for use in grayscale files */
-} png_color_16;
-typedef png_color_16 FAR * png_color_16p;
-typedef PNG_CONST png_color_16 FAR * png_const_color_16p;
-typedef png_color_16 FAR * FAR * png_color_16pp;
-
-typedef struct png_color_8_struct
-{
-   png_byte red;   /* for use in red green blue files */
-   png_byte green;
-   png_byte blue;
-   png_byte gray;  /* for use in grayscale files */
-   png_byte alpha; /* for alpha channel files */
-} png_color_8;
-typedef png_color_8 FAR * png_color_8p;
-typedef PNG_CONST png_color_8 FAR * png_const_color_8p;
-typedef png_color_8 FAR * FAR * png_color_8pp;
-
-/*
- * The following two structures are used for the in-core representation
- * of sPLT chunks.
- */
-typedef struct png_sPLT_entry_struct
-{
-   png_uint_16 red;
-   png_uint_16 green;
-   png_uint_16 blue;
-   png_uint_16 alpha;
-   png_uint_16 frequency;
-} png_sPLT_entry;
-typedef png_sPLT_entry FAR * png_sPLT_entryp;
-typedef PNG_CONST png_sPLT_entry FAR * png_const_sPLT_entryp;
-typedef png_sPLT_entry FAR * FAR * png_sPLT_entrypp;
-
-/*  When the depth of the sPLT palette is 8 bits, the color and alpha samples
- *  occupy the LSB of their respective members, and the MSB of each member
- *  is zero-filled.  The frequency member always occupies the full 16 bits.
- */
-
-typedef struct png_sPLT_struct
-{
-   png_charp name;           /* palette name */
-   png_byte depth;           /* depth of palette samples */
-   png_sPLT_entryp entries;  /* palette entries */
-   png_int_32 nentries;      /* number of palette entries */
-} png_sPLT_t;
-typedef png_sPLT_t FAR * png_sPLT_tp;
-typedef PNG_CONST png_sPLT_t FAR * png_const_sPLT_tp;
-typedef png_sPLT_t FAR * FAR * png_sPLT_tpp;
-
-#ifdef PNG_TEXT_SUPPORTED
-/* png_text holds the contents of a text/ztxt/itxt chunk in a PNG file,
- * and whether that contents is compressed or not.  The "key" field
- * points to a regular zero-terminated C string.  The "text" fields can be a
- * regular C string, an empty string, or a NULL pointer.
- * However, the structure returned by png_get_text() will always contain
- * the "text" field as a regular zero-terminated C string (possibly
- * empty), never a NULL pointer, so it can be safely used in printf() and
- * other string-handling functions.  Note that the "itxt_length", "lang", and
- * "lang_key" members of the structure only exist when the library is built
- * with iTXt chunk support.  Prior to libpng-1.4.0 the library was built by
- * default without iTXt support. Also note that when iTXt *is* supported,
- * the "lang" and "lang_key" fields contain NULL pointers when the
- * "compression" field contains * PNG_TEXT_COMPRESSION_NONE or
- * PNG_TEXT_COMPRESSION_zTXt. Note that the "compression value" is not the
- * same as what appears in the PNG tEXt/zTXt/iTXt chunk's "compression flag"
- * which is always 0 or 1, or its "compression method" which is always 0.
- */
-typedef struct png_text_struct
-{
-   int  compression;       /* compression value:
-                             -1: tEXt, none
-                              0: zTXt, deflate
-                              1: iTXt, none
-                              2: iTXt, deflate  */
-   png_charp key;          /* keyword, 1-79 character description of "text" */
-   png_charp text;         /* comment, may be an empty string (ie "")
-                              or a NULL pointer */
-   png_size_t text_length; /* length of the text string */
-   png_size_t itxt_length; /* length of the itxt string */
-   png_charp lang;         /* language code, 0-79 characters
-                              or a NULL pointer */
-   png_charp lang_key;     /* keyword translated UTF-8 string, 0 or more
-                              chars or a NULL pointer */
-} png_text;
-typedef png_text FAR * png_textp;
-typedef PNG_CONST png_text FAR * png_const_textp;
-typedef png_text FAR * FAR * png_textpp;
-#endif
-
-/* Supported compression types for text in PNG files (tEXt, and zTXt).
- * The values of the PNG_TEXT_COMPRESSION_ defines should NOT be changed. */
-#define PNG_TEXT_COMPRESSION_NONE_WR -3
-#define PNG_TEXT_COMPRESSION_zTXt_WR -2
-#define PNG_TEXT_COMPRESSION_NONE    -1
-#define PNG_TEXT_COMPRESSION_zTXt     0
-#define PNG_ITXT_COMPRESSION_NONE     1
-#define PNG_ITXT_COMPRESSION_zTXt     2
-#define PNG_TEXT_COMPRESSION_LAST     3  /* Not a valid value */
-
-/* png_time is a way to hold the time in an machine independent way.
- * Two conversions are provided, both from time_t and struct tm.  There
- * is no portable way to convert to either of these structures, as far
- * as I know.  If you know of a portable way, send it to me.  As a side
- * note - PNG has always been Year 2000 compliant!
- */
-typedef struct png_time_struct
-{
-   png_uint_16 year; /* full year, as in, 1995 */
-   png_byte month;   /* month of year, 1 - 12 */
-   png_byte day;     /* day of month, 1 - 31 */
-   png_byte hour;    /* hour of day, 0 - 23 */
-   png_byte minute;  /* minute of hour, 0 - 59 */
-   png_byte second;  /* second of minute, 0 - 60 (for leap seconds) */
-} png_time;
-typedef png_time FAR * png_timep;
-typedef PNG_CONST png_time FAR * png_const_timep;
-typedef png_time FAR * FAR * png_timepp;
-
-#if defined(PNG_UNKNOWN_CHUNKS_SUPPORTED) || \
-    defined(PNG_HANDLE_AS_UNKNOWN_SUPPORTED)
-/* png_unknown_chunk is a structure to hold queued chunks for which there is
- * no specific support.  The idea is that we can use this to queue
- * up private chunks for output even though the library doesn't actually
- * know about their semantics.
- */
-typedef struct png_unknown_chunk_t
-{
-    png_byte name[5];
-    png_byte *data;
-    png_size_t size;
-
-    /* libpng-using applications should NOT directly modify this byte. */
-    png_byte location; /* mode of operation at read time */
-}
-
-
-png_unknown_chunk;
-typedef png_unknown_chunk FAR * png_unknown_chunkp;
-typedef PNG_CONST png_unknown_chunk FAR * png_const_unknown_chunkp;
-typedef png_unknown_chunk FAR * FAR * png_unknown_chunkpp;
-#endif
-
-/* Values for the unknown chunk location byte */
-
-#define PNG_HAVE_IHDR  0x01
-#define PNG_HAVE_PLTE  0x02
-#define PNG_AFTER_IDAT 0x08
-
-/* The complete definition of png_info has, as of libpng-1.5.0,
- * been moved into a separate header file that is not accessible to
- * applications.  Read libpng-manual.txt or libpng.3 for more info.
- */
-typedef struct png_info_def png_info;
-typedef png_info FAR * png_infop;
-typedef PNG_CONST png_info FAR * png_const_infop;
-typedef png_info FAR * FAR * png_infopp;
-
-/* Maximum positive integer used in PNG is (2^31)-1 */
-#define PNG_UINT_31_MAX ((png_uint_32)0x7fffffffL)
-#define PNG_UINT_32_MAX ((png_uint_32)(-1))
-#define PNG_SIZE_MAX ((png_size_t)(-1))
-
-/* These are constants for fixed point values encoded in the
- * PNG specification manner (x100000)
- */
-#define PNG_FP_1    100000
-#define PNG_FP_HALF  50000
-#define PNG_FP_MAX  ((png_fixed_point)0x7fffffffL)
-#define PNG_FP_MIN  (-PNG_FP_MAX)
-
-/* These describe the color_type field in png_info. */
-/* color type masks */
-#define PNG_COLOR_MASK_PALETTE    1
-#define PNG_COLOR_MASK_COLOR      2
-#define PNG_COLOR_MASK_ALPHA      4
-
-/* color types.  Note that not all combinations are legal */
-#define PNG_COLOR_TYPE_GRAY 0
-#define PNG_COLOR_TYPE_PALETTE  (PNG_COLOR_MASK_COLOR | PNG_COLOR_MASK_PALETTE)
-#define PNG_COLOR_TYPE_RGB        (PNG_COLOR_MASK_COLOR)
-#define PNG_COLOR_TYPE_RGB_ALPHA  (PNG_COLOR_MASK_COLOR | PNG_COLOR_MASK_ALPHA)
-#define PNG_COLOR_TYPE_GRAY_ALPHA (PNG_COLOR_MASK_ALPHA)
-/* aliases */
-#define PNG_COLOR_TYPE_RGBA  PNG_COLOR_TYPE_RGB_ALPHA
-#define PNG_COLOR_TYPE_GA  PNG_COLOR_TYPE_GRAY_ALPHA
-
-/* This is for compression type. PNG 1.0-1.2 only define the single type. */
-#define PNG_COMPRESSION_TYPE_BASE 0 /* Deflate method 8, 32K window */
-#define PNG_COMPRESSION_TYPE_DEFAULT PNG_COMPRESSION_TYPE_BASE
-
-/* This is for filter type. PNG 1.0-1.2 only define the single type. */
-#define PNG_FILTER_TYPE_BASE      0 /* Single row per-byte filtering */
-#define PNG_INTRAPIXEL_DIFFERENCING 64 /* Used only in MNG datastreams */
-#define PNG_FILTER_TYPE_DEFAULT   PNG_FILTER_TYPE_BASE
-
-/* These are for the interlacing type.  These values should NOT be changed. */
-#define PNG_INTERLACE_NONE        0 /* Non-interlaced image */
-#define PNG_INTERLACE_ADAM7       1 /* Adam7 interlacing */
-#define PNG_INTERLACE_LAST        2 /* Not a valid value */
-
-/* These are for the oFFs chunk.  These values should NOT be changed. */
-#define PNG_OFFSET_PIXEL          0 /* Offset in pixels */
-#define PNG_OFFSET_MICROMETER     1 /* Offset in micrometers (1/10^6 meter) */
-#define PNG_OFFSET_LAST           2 /* Not a valid value */
-
-/* These are for the pCAL chunk.  These values should NOT be changed. */
-#define PNG_EQUATION_LINEAR       0 /* Linear transformation */
-#define PNG_EQUATION_BASE_E       1 /* Exponential base e transform */
-#define PNG_EQUATION_ARBITRARY    2 /* Arbitrary base exponential transform */
-#define PNG_EQUATION_HYPERBOLIC   3 /* Hyperbolic sine transformation */
-#define PNG_EQUATION_LAST         4 /* Not a valid value */
-
-/* These are for the sCAL chunk.  These values should NOT be changed. */
-#define PNG_SCALE_UNKNOWN         0 /* unknown unit (image scale) */
-#define PNG_SCALE_METER           1 /* meters per pixel */
-#define PNG_SCALE_RADIAN          2 /* radians per pixel */
-#define PNG_SCALE_LAST            3 /* Not a valid value */
-
-/* These are for the pHYs chunk.  These values should NOT be changed. */
-#define PNG_RESOLUTION_UNKNOWN    0 /* pixels/unknown unit (aspect ratio) */
-#define PNG_RESOLUTION_METER      1 /* pixels/meter */
-#define PNG_RESOLUTION_LAST       2 /* Not a valid value */
-
-/* These are for the sRGB chunk.  These values should NOT be changed. */
-#define PNG_sRGB_INTENT_PERCEPTUAL 0
-#define PNG_sRGB_INTENT_RELATIVE   1
-#define PNG_sRGB_INTENT_SATURATION 2
-#define PNG_sRGB_INTENT_ABSOLUTE   3
-#define PNG_sRGB_INTENT_LAST       4 /* Not a valid value */
-
-/* This is for text chunks */
-#define PNG_KEYWORD_MAX_LENGTH     79
-
-/* Maximum number of entries in PLTE/sPLT/tRNS arrays */
-#define PNG_MAX_PALETTE_LENGTH    256
-
-/* These determine if an ancillary chunk's data has been successfully read
- * from the PNG header, or if the application has filled in the corresponding
- * data in the info_struct to be written into the output file.  The values
- * of the PNG_INFO_<chunk> defines should NOT be changed.
- */
-#define PNG_INFO_gAMA 0x0001
-#define PNG_INFO_sBIT 0x0002
-#define PNG_INFO_cHRM 0x0004
-#define PNG_INFO_PLTE 0x0008
-#define PNG_INFO_tRNS 0x0010
-#define PNG_INFO_bKGD 0x0020
-#define PNG_INFO_hIST 0x0040
-#define PNG_INFO_pHYs 0x0080
-#define PNG_INFO_oFFs 0x0100
-#define PNG_INFO_tIME 0x0200
-#define PNG_INFO_pCAL 0x0400
-#define PNG_INFO_sRGB 0x0800   /* GR-P, 0.96a */
-#define PNG_INFO_iCCP 0x1000   /* ESR, 1.0.6 */
-#define PNG_INFO_sPLT 0x2000   /* ESR, 1.0.6 */
-#define PNG_INFO_sCAL 0x4000   /* ESR, 1.0.6 */
-#define PNG_INFO_IDAT 0x8000   /* ESR, 1.0.6 */
-
-/* This is used for the transformation routines, as some of them
- * change these values for the row.  It also should enable using
- * the routines for other purposes.
- */
-typedef struct png_row_info_struct
-{
-   png_uint_32 width;    /* width of row */
-   png_size_t rowbytes;  /* number of bytes in row */
-   png_byte color_type;  /* color type of row */
-   png_byte bit_depth;   /* bit depth of row */
-   png_byte channels;    /* number of channels (1, 2, 3, or 4) */
-   png_byte pixel_depth; /* bits per pixel (depth * channels) */
-} png_row_info;
-
-typedef png_row_info FAR * png_row_infop;
-typedef png_row_info FAR * FAR * png_row_infopp;
-
-/* The complete definition of png_struct has, as of libpng-1.5.0,
- * been moved into a separate header file that is not accessible to
- * applications.  Read libpng-manual.txt or libpng.3 for more info.
- */
-typedef struct png_struct_def png_struct;
-typedef PNG_CONST png_struct FAR * png_const_structp;
-typedef png_struct FAR * png_structp;
-
-/* These are the function types for the I/O functions and for the functions
- * that allow the user to override the default I/O functions with his or her
- * own.  The png_error_ptr type should match that of user-supplied warning
- * and error functions, while the png_rw_ptr type should match that of the
- * user read/write data functions.  Note that the 'write' function must not
- * modify the buffer it is passed. The 'read' function, on the other hand, is
- * expected to return the read data in the buffer.
- */
-typedef PNG_CALLBACK(void, *png_error_ptr, (png_structp, png_const_charp));
-typedef PNG_CALLBACK(void, *png_rw_ptr, (png_structp, png_bytep, png_size_t));
-typedef PNG_CALLBACK(void, *png_flush_ptr, (png_structp));
-typedef PNG_CALLBACK(void, *png_read_status_ptr, (png_structp, png_uint_32,
-    int));
-typedef PNG_CALLBACK(void, *png_write_status_ptr, (png_structp, png_uint_32,
-    int));
-
-#ifdef PNG_PROGRESSIVE_READ_SUPPORTED
-typedef PNG_CALLBACK(void, *png_progressive_info_ptr, (png_structp, png_infop));
-typedef PNG_CALLBACK(void, *png_progressive_end_ptr, (png_structp, png_infop));
-
-/* The following callback receives png_uint_32 row_number, int pass for the
- * png_bytep data of the row.  When transforming an interlaced image the
- * row number is the row number within the sub-image of the interlace pass, so
- * the value will increase to the height of the sub-image (not the full image)
- * then reset to 0 for the next pass.
- *
- * Use PNG_ROW_FROM_PASS_ROW(row, pass) and PNG_COL_FROM_PASS_COL(col, pass) to
- * find the output pixel (x,y) given an interlaced sub-image pixel
- * (row,col,pass).  (See below for these macros.)
- */
-typedef PNG_CALLBACK(void, *png_progressive_row_ptr, (png_structp, png_bytep,
-    png_uint_32, int));
-#endif
-
-#if defined(PNG_READ_USER_TRANSFORM_SUPPORTED) || \
-    defined(PNG_WRITE_USER_TRANSFORM_SUPPORTED)
-typedef PNG_CALLBACK(void, *png_user_transform_ptr, (png_structp, png_row_infop,
-    png_bytep));
-#endif
-
-#ifdef PNG_USER_CHUNKS_SUPPORTED
-typedef PNG_CALLBACK(int, *png_user_chunk_ptr, (png_structp,
-    png_unknown_chunkp));
-#endif
-#ifdef PNG_UNKNOWN_CHUNKS_SUPPORTED
-typedef PNG_CALLBACK(void, *png_unknown_chunk_ptr, (png_structp));
-#endif
-
-#ifdef PNG_SETJMP_SUPPORTED
-/* This must match the function definition in <setjmp.h>, and the application
- * must include this before png.h to obtain the definition of jmp_buf.  The
- * function is required to be PNG_NORETURN, but this is not checked.  If the
- * function does return the application will crash via an abort() or similar
- * system level call.
- *
- * If you get a warning here while building the library you may need to make
- * changes to ensure that pnglibconf.h records the calling convention used by
- * your compiler.  This may be very difficult - try using a different compiler
- * to build the library!
- */
-PNG_FUNCTION(void, (PNGCAPI *png_longjmp_ptr), PNGARG((jmp_buf, int)), typedef);
-#endif
-
-/* Transform masks for the high-level interface */
-#define PNG_TRANSFORM_IDENTITY       0x0000    /* read and write */
-#define PNG_TRANSFORM_STRIP_16       0x0001    /* read only */
-#define PNG_TRANSFORM_STRIP_ALPHA    0x0002    /* read only */
-#define PNG_TRANSFORM_PACKING        0x0004    /* read and write */
-#define PNG_TRANSFORM_PACKSWAP       0x0008    /* read and write */
-#define PNG_TRANSFORM_EXPAND         0x0010    /* read only */
-#define PNG_TRANSFORM_INVERT_MONO    0x0020    /* read and write */
-#define PNG_TRANSFORM_SHIFT          0x0040    /* read and write */
-#define PNG_TRANSFORM_BGR            0x0080    /* read and write */
-#define PNG_TRANSFORM_SWAP_ALPHA     0x0100    /* read and write */
-#define PNG_TRANSFORM_SWAP_ENDIAN    0x0200    /* read and write */
-#define PNG_TRANSFORM_INVERT_ALPHA   0x0400    /* read and write */
-#define PNG_TRANSFORM_STRIP_FILLER   0x0800    /* write only */
-/* Added to libpng-1.2.34 */
-#define PNG_TRANSFORM_STRIP_FILLER_BEFORE PNG_TRANSFORM_STRIP_FILLER
-#define PNG_TRANSFORM_STRIP_FILLER_AFTER 0x1000 /* write only */
-/* Added to libpng-1.4.0 */
-#define PNG_TRANSFORM_GRAY_TO_RGB   0x2000      /* read only */
-/* Added to libpng-1.5.4 */
-#define PNG_TRANSFORM_EXPAND_16     0x4000      /* read only */
-#define PNG_TRANSFORM_SCALE_16      0x8000      /* read only */
-
-/* Flags for MNG supported features */
-#define PNG_FLAG_MNG_EMPTY_PLTE     0x01
-#define PNG_FLAG_MNG_FILTER_64      0x04
-#define PNG_ALL_MNG_FEATURES        0x05
-
-/* NOTE: prior to 1.5 these functions had no 'API' style declaration,
- * this allowed the zlib default functions to be used on Windows
- * platforms.  In 1.5 the zlib default malloc (which just calls malloc and
- * ignores the first argument) should be completely compatible with the
- * following.
- */
-typedef PNG_CALLBACK(png_voidp, *png_malloc_ptr, (png_structp,
-    png_alloc_size_t));
-typedef PNG_CALLBACK(void, *png_free_ptr, (png_structp, png_voidp));
-
-typedef png_struct FAR * FAR * png_structpp;
-
-/* Section 3: exported functions
- * Here are the function definitions most commonly used.  This is not
- * the place to find out how to use libpng.  See libpng-manual.txt for the
- * full explanation, see example.c for the summary.  This just provides
- * a simple one line description of the use of each function.
- *
- * The PNG_EXPORT() and PNG_EXPORTA() macros used below are defined in
- * pngconf.h and in the *.dfn files in the scripts directory.
- *
- *   PNG_EXPORT(ordinal, type, name, (args));
- *
- *       ordinal:    ordinal that is used while building
- *                   *.def files. The ordinal value is only
- *                   relevant when preprocessing png.h with
- *                   the *.dfn files for building symbol table
- *                   entries, and are removed by pngconf.h.
- *       type:       return type of the function
- *       name:       function name
- *       args:       function arguments, with types
- *
- * When we wish to append attributes to a function prototype we use
- * the PNG_EXPORTA() macro instead.
- *
- *   PNG_EXPORTA(ordinal, type, name, (args), attributes);
- *
- *       ordinal, type, name, and args: same as in PNG_EXPORT().
- *       attributes: function attributes
- */
-
-/* Returns the version number of the library */
-PNG_EXPORT(1, png_uint_32, png_access_version_number, (void));
-
-/* Tell lib we have already handled the first <num_bytes> magic bytes.
- * Handling more than 8 bytes from the beginning of the file is an error.
- */
-PNG_EXPORT(2, void, dg_png_set_sig_bytes, (png_structp png_ptr, int num_bytes));
-
-/* Check sig[start] through sig[start + num_to_check - 1] to see if it's a
- * PNG file.  Returns zero if the supplied bytes match the 8-byte PNG
- * signature, and non-zero otherwise.  Having num_to_check == 0 or
- * start > 7 will always fail (ie return non-zero).
- */
-PNG_EXPORT(3, int, dg_png_sig_cmp, (png_const_bytep sig, png_size_t start,
-    png_size_t num_to_check));
-
-/* Simple signature checking function.  This is the same as calling
- * png_check_sig(sig, n) := !png_sig_cmp(sig, 0, n).
- */
-#define png_check_sig(sig, n) !png_sig_cmp((sig), 0, (n))
-
-/* Allocate and initialize png_ptr struct for reading, and any other memory. */
-PNG_EXPORTA(4, png_structp, dg_png_create_read_struct,
-    (png_const_charp user_png_ver, png_voidp error_ptr,
-    png_error_ptr error_fn, png_error_ptr warn_fn),
-    PNG_ALLOCATED);
-
-/* Allocate and initialize png_ptr struct for writing, and any other memory */
-PNG_EXPORTA(5, png_structp, png_create_write_struct,
-    (png_const_charp user_png_ver, png_voidp error_ptr, png_error_ptr error_fn,
-    png_error_ptr warn_fn),
-    PNG_ALLOCATED);
-
-PNG_EXPORT(6, png_size_t, png_get_compression_buffer_size,
-    (png_const_structp png_ptr));
-
-PNG_EXPORT(7, void, png_set_compression_buffer_size, (png_structp png_ptr,
-    png_size_t size));
-
-/* Moved from pngconf.h in 1.4.0 and modified to ensure setjmp/longjmp
- * match up.
- */
-#ifdef PNG_SETJMP_SUPPORTED
-/* This function returns the jmp_buf built in to *png_ptr.  It must be
- * supplied with an appropriate 'longjmp' function to use on that jmp_buf
- * unless the default error function is overridden in which case NULL is
- * acceptable.  The size of the jmp_buf is checked against the actual size
- * allocated by the library - the call will return NULL on a mismatch
- * indicating an ABI mismatch.
- */
-PNG_EXPORT(8, jmp_buf*, dg_png_set_longjmp_fn, (png_structp png_ptr,
-    png_longjmp_ptr longjmp_fn, size_t jmp_buf_size));
-#  define dg_png_jmpbuf(png_ptr) \
-      (*dg_png_set_longjmp_fn((png_ptr), longjmp, sizeof (jmp_buf)))
-#else
-#  define dg_png_jmpbuf(png_ptr) \
-      (LIBPNG_WAS_COMPILED_WITH__PNG_NO_SETJMP)
-#endif
-/* This function should be used by libpng applications in place of
- * longjmp(png_ptr->jmpbuf, val).  If longjmp_fn() has been set, it
- * will use it; otherwise it will call PNG_ABORT().  This function was
- * added in libpng-1.5.0.
- */
-PNG_EXPORTA(9, void, png_longjmp, (png_structp png_ptr, int val),
-    PNG_NORETURN);
-
-#ifdef PNG_READ_SUPPORTED
-/* Reset the compression stream */
-PNG_EXPORT(10, int, png_reset_zstream, (png_structp png_ptr));
-#endif
-
-/* New functions added in libpng-1.0.2 (not enabled by default until 1.2.0) */
-#ifdef PNG_USER_MEM_SUPPORTED
-PNG_EXPORTA(11, png_structp, png_create_read_struct_2,
-    (png_const_charp user_png_ver, png_voidp error_ptr, png_error_ptr error_fn,
-    png_error_ptr warn_fn,
-    png_voidp mem_ptr, png_malloc_ptr malloc_fn, png_free_ptr free_fn),
-    PNG_ALLOCATED);
-PNG_EXPORTA(12, png_structp, png_create_write_struct_2,
-    (png_const_charp user_png_ver, png_voidp error_ptr, png_error_ptr error_fn,
-    png_error_ptr warn_fn,
-    png_voidp mem_ptr, png_malloc_ptr malloc_fn, png_free_ptr free_fn),
-    PNG_ALLOCATED);
-#endif
-
-/* Write the PNG file signature. */
-PNG_EXPORT(13, void, png_write_sig, (png_structp png_ptr));
-
-/* Write a PNG chunk - size, type, (optional) data, CRC. */
-PNG_EXPORT(14, void, png_write_chunk, (png_structp png_ptr, png_const_bytep
-    chunk_name, png_const_bytep data, png_size_t length));
-
-/* Write the start of a PNG chunk - length and chunk name. */
-PNG_EXPORT(15, void, png_write_chunk_start, (png_structp png_ptr,
-    png_const_bytep chunk_name, png_uint_32 length));
-
-/* Write the data of a PNG chunk started with png_write_chunk_start(). */
-PNG_EXPORT(16, void, png_write_chunk_data, (png_structp png_ptr,
-    png_const_bytep data, png_size_t length));
-
-/* Finish a chunk started with png_write_chunk_start() (includes CRC). */
-PNG_EXPORT(17, void, png_write_chunk_end, (png_structp png_ptr));
-
-/* Allocate and initialize the info structure */
-PNG_EXPORTA(18, png_infop, dg_png_create_info_struct, (png_structp png_ptr),
-    PNG_ALLOCATED);
-
-PNG_EXPORT(19, void, png_info_init_3, (png_infopp info_ptr,
-    png_size_t png_info_struct_size));
-
-/* Writes all the PNG information before the image. */
-PNG_EXPORT(20, void, png_write_info_before_PLTE,
-    (png_structp png_ptr, png_infop info_ptr));
-PNG_EXPORT(21, void, png_write_info,
-    (png_structp png_ptr, png_infop info_ptr));
-
-#ifdef PNG_SEQUENTIAL_READ_SUPPORTED
-/* Read the information before the actual image data. */
-PNG_EXPORT(22, void, dg_png_read_info,
-    (png_structp png_ptr, png_infop info_ptr));
-#endif
-
-#ifdef PNG_TIME_RFC1123_SUPPORTED
-PNG_EXPORT(23, png_const_charp, png_convert_to_rfc1123,
-    (png_structp png_ptr,
-    png_const_timep ptime));
-#endif
-
-#ifdef PNG_CONVERT_tIME_SUPPORTED
-/* Convert from a struct tm to png_time */
-PNG_EXPORT(24, void, png_convert_from_struct_tm, (png_timep ptime,
-    PNG_CONST struct tm FAR * ttime));
-
-/* Convert from time_t to png_time.  Uses gmtime() */
-PNG_EXPORT(25, void, png_convert_from_time_t,
-    (png_timep ptime, time_t ttime));
-#endif /* PNG_CONVERT_tIME_SUPPORTED */
-
-#ifdef PNG_READ_EXPAND_SUPPORTED
-/* Expand data to 24-bit RGB, or 8-bit grayscale, with alpha if available. */
-PNG_EXPORT(26, void, png_set_expand, (png_structp png_ptr));
-PNG_EXPORT(27, void, png_set_expand_gray_1_2_4_to_8, (png_structp png_ptr));
-PNG_EXPORT(28, void, png_set_palette_to_rgb, (png_structp png_ptr));
-PNG_EXPORT(29, void, png_set_tRNS_to_alpha, (png_structp png_ptr));
-#endif
-
-#ifdef PNG_READ_EXPAND_16_SUPPORTED
-/* Expand to 16-bit channels, forces conversion of palette to RGB and expansion
- * of a tRNS chunk if present.
- */
-PNG_EXPORT(221, void, png_set_expand_16, (png_structp png_ptr));
-#endif
-
-#if defined(PNG_READ_BGR_SUPPORTED) || defined(PNG_WRITE_BGR_SUPPORTED)
-/* Use blue, green, red order for pixels. */
-PNG_EXPORT(30, void, png_set_bgr, (png_structp png_ptr));
-#endif
-
-#ifdef PNG_READ_GRAY_TO_RGB_SUPPORTED
-/* Expand the grayscale to 24-bit RGB if necessary. */
-PNG_EXPORT(31, void, png_set_gray_to_rgb, (png_structp png_ptr));
-#endif
-
-#ifdef PNG_READ_RGB_TO_GRAY_SUPPORTED
-/* Reduce RGB to grayscale. */
-#define PNG_ERROR_ACTION_NONE  1
-#define PNG_ERROR_ACTION_WARN  2
-#define PNG_ERROR_ACTION_ERROR 3
-#define PNG_RGB_TO_GRAY_DEFAULT (-1)/*for red/green coefficients*/
-
-PNG_FP_EXPORT(32, void, png_set_rgb_to_gray, (png_structp png_ptr,
-    int error_action, double red, double green))
-PNG_FIXED_EXPORT(33, void, png_set_rgb_to_gray_fixed, (png_structp png_ptr,
-    int error_action, png_fixed_point red, png_fixed_point green))
-
-PNG_EXPORT(34, png_byte, png_get_rgb_to_gray_status, (png_const_structp
-    png_ptr));
-#endif
-
-#ifdef PNG_BUILD_GRAYSCALE_PALETTE_SUPPORTED
-PNG_EXPORT(35, void, png_build_grayscale_palette, (int bit_depth,
-    png_colorp palette));
-#endif
-
-#ifdef PNG_READ_ALPHA_MODE_SUPPORTED
-/* How the alpha channel is interpreted - this affects how the color channels of
- * a PNG file are returned when an alpha channel, or tRNS chunk in a palette
- * file, is present.
- *
- * This has no effect on the way pixels are written into a PNG output
- * datastream. The color samples in a PNG datastream are never premultiplied
- * with the alpha samples.
- *
- * The default is to return data according to the PNG specification: the alpha
- * channel is a linear measure of the contribution of the pixel to the
- * corresponding composited pixel.  The gamma encoded color channels must be
- * scaled according to the contribution and to do this it is necessary to undo
- * the encoding, scale the color values, perform the composition and reencode
- * the values.  This is the 'PNG' mode.
- *
- * The alternative is to 'associate' the alpha with the color information by
- * storing color channel values that have been scaled by the alpha.  The
- * advantage is that the color channels can be resampled (the image can be
- * scaled) in this form.  The disadvantage is that normal practice is to store
- * linear, not (gamma) encoded, values and this requires 16-bit channels for
- * still images rather than the 8-bit channels that are just about sufficient if
- * gamma encoding is used.  In addition all non-transparent pixel values,
- * including completely opaque ones, must be gamma encoded to produce the final
- * image.  This is the 'STANDARD', 'ASSOCIATED' or 'PREMULTIPLIED' mode (the
- * latter being the two common names for associated alpha color channels.)
- *
- * Since it is not necessary to perform arithmetic on opaque color values so
- * long as they are not to be resampled and are in the final color space it is
- * possible to optimize the handling of alpha by storing the opaque pixels in
- * the PNG format (adjusted for the output color space) while storing partially
- * opaque pixels in the standard, linear, format.  The accuracy required for
- * standard alpha composition is relatively low, because the pixels are
- * isolated, therefore typically the accuracy loss in storing 8-bit linear
- * values is acceptable.  (This is not true if the alpha channel is used to
- * simulate transparency over large areas - use 16 bits or the PNG mode in
- * this case!)  This is the 'OPTIMIZED' mode.  For this mode a pixel is
- * treated as opaque only if the alpha value is equal to the maximum value.
- *
- * The final choice is to gamma encode the alpha channel as well.  This is
- * broken because, in practice, no implementation that uses this choice
- * correctly undoes the encoding before handling alpha composition.  Use this
- * choice only if other serious errors in the software or hardware you use
- * mandate it; the typical serious error is for dark halos to appear around
- * opaque areas of the composited PNG image because of arithmetic overflow.
- *
- * The API function png_set_alpha_mode specifies which of these choices to use
- * with an enumerated 'mode' value and the gamma of the required output:
- */
-#define PNG_ALPHA_PNG           0 /* according to the PNG standard */
-#define PNG_ALPHA_STANDARD      1 /* according to Porter/Duff */
-#define PNG_ALPHA_ASSOCIATED    1 /* as above; this is the normal practice */
-#define PNG_ALPHA_PREMULTIPLIED 1 /* as above */
-#define PNG_ALPHA_OPTIMIZED     2 /* 'PNG' for opaque pixels, else 'STANDARD' */
-#define PNG_ALPHA_BROKEN        3 /* the alpha channel is gamma encoded */
-
-PNG_FP_EXPORT(227, void, png_set_alpha_mode, (png_structp png_ptr, int mode,
-    double output_gamma))
-PNG_FIXED_EXPORT(228, void, png_set_alpha_mode_fixed, (png_structp png_ptr,
-    int mode, png_fixed_point output_gamma))
-#endif
-
-#if defined(PNG_READ_GAMMA_SUPPORTED) || defined(PNG_READ_ALPHA_MODE_SUPPORTED)
-/* The output_gamma value is a screen gamma in libpng terminology: it expresses
- * how to decode the output values, not how they are encoded.  The values used
- * correspond to the normal numbers used to describe the overall gamma of a
- * computer display system; for example 2.2 for an sRGB conformant system.  The
- * values are scaled by 100000 in the _fixed version of the API (so 220000 for
- * sRGB.)
- *
- * The inverse of the value is always used to provide a default for the PNG file
- * encoding if it has no gAMA chunk and if png_set_gamma() has not been called
- * to override the PNG gamma information.
- *
- * When the ALPHA_OPTIMIZED mode is selected the output gamma is used to encode
- * opaque pixels however pixels with lower alpha values are not encoded,
- * regardless of the output gamma setting.
- *
- * When the standard Porter Duff handling is requested with mode 1 the output
- * encoding is set to be linear and the output_gamma value is only relevant
- * as a default for input data that has no gamma information.  The linear output
- * encoding will be overridden if png_set_gamma() is called - the results may be
- * highly unexpected!
- *
- * The following numbers are derived from the sRGB standard and the research
- * behind it.  sRGB is defined to be approximated by a PNG gAMA chunk value of
- * 0.45455 (1/2.2) for PNG.  The value implicitly includes any viewing
- * correction required to take account of any differences in the color
- * environment of the original scene and the intended display environment; the
- * value expresses how to *decode* the image for display, not how the original
- * data was *encoded*.
- *
- * sRGB provides a peg for the PNG standard by defining a viewing environment.
- * sRGB itself, and earlier TV standards, actually use a more complex transform
- * (a linear portion then a gamma 2.4 power law) than PNG can express.  (PNG is
- * limited to simple power laws.)  By saying that an image for direct display on
- * an sRGB conformant system should be stored with a gAMA chunk value of 45455
- * (11.3.3.2 and 11.3.3.5 of the ISO PNG specification) the PNG specification
- * makes it possible to derive values for other display systems and
- * environments.
- *
- * The Mac value is deduced from the sRGB based on an assumption that the actual
- * extra viewing correction used in early Mac display systems was implemented as
- * a power 1.45 lookup table.
- *
- * Any system where a programmable lookup table is used or where the behavior of
- * the final display device characteristics can be changed requires system
- * specific code to obtain the current characteristic.  However this can be
- * difficult and most PNG gamma correction only requires an approximate value.
- *
- * By default, if png_set_alpha_mode() is not called, libpng assumes that all
- * values are unencoded, linear, values and that the output device also has a
- * linear characteristic.  This is only very rarely correct - it is invariably
- * better to call png_set_alpha_mode() with PNG_DEFAULT_sRGB than rely on the
- * default if you don't know what the right answer is!
- *
- * The special value PNG_GAMMA_MAC_18 indicates an older Mac system (pre Mac OS
- * 10.6) which used a correction table to implement a somewhat lower gamma on an
- * otherwise sRGB system.
- *
- * Both these values are reserved (not simple gamma values) in order to allow
- * more precise correction internally in the future.
- *
- * NOTE: the following values can be passed to either the fixed or floating
- * point APIs, but the floating point API will also accept floating point
- * values.
- */
-#define PNG_DEFAULT_sRGB -1       /* sRGB gamma and color space */
-#define PNG_GAMMA_MAC_18 -2       /* Old Mac '1.8' gamma and color space */
-#define PNG_GAMMA_sRGB   220000   /* Television standards--matches sRGB gamma */
-#define PNG_GAMMA_LINEAR PNG_FP_1 /* Linear */
-#endif
-
-/* The following are examples of calls to png_set_alpha_mode to achieve the
- * required overall gamma correction and, where necessary, alpha
- * premultiplication.
- *
- * png_set_alpha_mode(pp, PNG_ALPHA_PNG, PNG_DEFAULT_sRGB);
- *    This is the default libpng handling of the alpha channel - it is not
- *    pre-multiplied into the color components.  In addition the call states
- *    that the output is for a sRGB system and causes all PNG files without gAMA
- *    chunks to be assumed to be encoded using sRGB.
- *
- * png_set_alpha_mode(pp, PNG_ALPHA_PNG, PNG_GAMMA_MAC);
- *    In this case the output is assumed to be something like an sRGB conformant
- *    display preceeded by a power-law lookup table of power 1.45.  This is how
- *    early Mac systems behaved.
- *
- * png_set_alpha_mode(pp, PNG_ALPHA_STANDARD, PNG_GAMMA_LINEAR);
- *    This is the classic Jim Blinn approach and will work in academic
- *    environments where everything is done by the book.  It has the shortcoming
- *    of assuming that input PNG data with no gamma information is linear - this
- *    is unlikely to be correct unless the PNG files where generated locally.
- *    Most of the time the output precision will be so low as to show
- *    significant banding in dark areas of the image.
- *
- * png_set_expand_16(pp);
- * png_set_alpha_mode(pp, PNG_ALPHA_STANDARD, PNG_DEFAULT_sRGB);
- *    This is a somewhat more realistic Jim Blinn inspired approach.  PNG files
- *    are assumed to have the sRGB encoding if not marked with a gamma value and
- *    the output is always 16 bits per component.  This permits accurate scaling
- *    and processing of the data.  If you know that your input PNG files were
- *    generated locally you might need to replace PNG_DEFAULT_sRGB with the
- *    correct value for your system.
- *
- * png_set_alpha_mode(pp, PNG_ALPHA_OPTIMIZED, PNG_DEFAULT_sRGB);
- *    If you just need to composite the PNG image onto an existing background
- *    and if you control the code that does this you can use the optimization
- *    setting.  In this case you just copy completely opaque pixels to the
- *    output.  For pixels that are not completely transparent (you just skip
- *    those) you do the composition math using png_composite or png_composite_16
- *    below then encode the resultant 8-bit or 16-bit values to match the output
- *    encoding.
- *
- * Other cases
- *    If neither the PNG nor the standard linear encoding work for you because
- *    of the software or hardware you use then you have a big problem.  The PNG
- *    case will probably result in halos around the image.  The linear encoding
- *    will probably result in a washed out, too bright, image (it's actually too
- *    contrasty.)  Try the ALPHA_OPTIMIZED mode above - this will probably
- *    substantially reduce the halos.  Alternatively try:
- *
- * png_set_alpha_mode(pp, PNG_ALPHA_BROKEN, PNG_DEFAULT_sRGB);
- *    This option will also reduce the halos, but there will be slight dark
- *    halos round the opaque parts of the image where the background is light.
- *    In the OPTIMIZED mode the halos will be light halos where the background
- *    is dark.  Take your pick - the halos are unavoidable unless you can get
- *    your hardware/software fixed!  (The OPTIMIZED approach is slightly
- *    faster.)
- *
- * When the default gamma of PNG files doesn't match the output gamma.
- *    If you have PNG files with no gamma information png_set_alpha_mode allows
- *    you to provide a default gamma, but it also sets the ouput gamma to the
- *    matching value.  If you know your PNG files have a gamma that doesn't
- *    match the output you can take advantage of the fact that
- *    png_set_alpha_mode always sets the output gamma but only sets the PNG
- *    default if it is not already set:
- *
- * png_set_alpha_mode(pp, PNG_ALPHA_PNG, PNG_DEFAULT_sRGB);
- * png_set_alpha_mode(pp, PNG_ALPHA_PNG, PNG_GAMMA_MAC);
- *    The first call sets both the default and the output gamma values, the
- *    second call overrides the output gamma without changing the default.  This
- *    is easier than achieving the same effect with png_set_gamma.  You must use
- *    PNG_ALPHA_PNG for the first call - internal checking in png_set_alpha will
- *    fire if more than one call to png_set_alpha_mode and png_set_background is
- *    made in the same read operation, however multiple calls with PNG_ALPHA_PNG
- *    are ignored.
- */
-
-#ifdef PNG_READ_STRIP_ALPHA_SUPPORTED
-PNG_EXPORT(36, void, png_set_strip_alpha, (png_structp png_ptr));
-#endif
-
-#if defined(PNG_READ_SWAP_ALPHA_SUPPORTED) || \
-    defined(PNG_WRITE_SWAP_ALPHA_SUPPORTED)
-PNG_EXPORT(37, void, png_set_swap_alpha, (png_structp png_ptr));
-#endif
-
-#if defined(PNG_READ_INVERT_ALPHA_SUPPORTED) || \
-    defined(PNG_WRITE_INVERT_ALPHA_SUPPORTED)
-PNG_EXPORT(38, void, png_set_invert_alpha, (png_structp png_ptr));
-#endif
-
-#if defined(PNG_READ_FILLER_SUPPORTED) || defined(PNG_WRITE_FILLER_SUPPORTED)
-/* Add a filler byte to 8-bit Gray or 24-bit RGB images. */
-PNG_EXPORT(39, void, png_set_filler, (png_structp png_ptr, png_uint_32 filler,
-    int flags));
-/* The values of the PNG_FILLER_ defines should NOT be changed */
-#  define PNG_FILLER_BEFORE 0
-#  define PNG_FILLER_AFTER 1
-/* Add an alpha byte to 8-bit Gray or 24-bit RGB images. */
-PNG_EXPORT(40, void, png_set_add_alpha,
-    (png_structp png_ptr, png_uint_32 filler,
-    int flags));
-#endif /* PNG_READ_FILLER_SUPPORTED || PNG_WRITE_FILLER_SUPPORTED */
-
-#if defined(PNG_READ_SWAP_SUPPORTED) || defined(PNG_WRITE_SWAP_SUPPORTED)
-/* Swap bytes in 16-bit depth files. */
-PNG_EXPORT(41, void, png_set_swap, (png_structp png_ptr));
-#endif
-
-#if defined(PNG_READ_PACK_SUPPORTED) || defined(PNG_WRITE_PACK_SUPPORTED)
-/* Use 1 byte per pixel in 1, 2, or 4-bit depth files. */
-PNG_EXPORT(42, void, png_set_packing, (png_structp png_ptr));
-#endif
-
-#if defined(PNG_READ_PACKSWAP_SUPPORTED) || \
-    defined(PNG_WRITE_PACKSWAP_SUPPORTED)
-/* Swap packing order of pixels in bytes. */
-PNG_EXPORT(43, void, png_set_packswap, (png_structp png_ptr));
-#endif
-
-#if defined(PNG_READ_SHIFT_SUPPORTED) || defined(PNG_WRITE_SHIFT_SUPPORTED)
-/* Converts files to legal bit depths. */
-PNG_EXPORT(44, void, png_set_shift, (png_structp png_ptr, png_const_color_8p
-    true_bits));
-#endif
-
-#if defined(PNG_READ_INTERLACING_SUPPORTED) || \
-    defined(PNG_WRITE_INTERLACING_SUPPORTED)
-/* Have the code handle the interlacing.  Returns the number of passes.
- * MUST be called before png_read_update_info or png_start_read_image,
- * otherwise it will not have the desired effect.  Note that it is still
- * necessary to call png_read_row or png_read_rows png_get_image_height
- * times for each pass.
-*/
-PNG_EXPORT(45, int, dg_png_set_interlace_handling, (png_structp png_ptr));
-#endif
-
-#if defined(PNG_READ_INVERT_SUPPORTED) || defined(PNG_WRITE_INVERT_SUPPORTED)
-/* Invert monochrome files */
-PNG_EXPORT(46, void, png_set_invert_mono, (png_structp png_ptr));
-#endif
-
-#ifdef PNG_READ_BACKGROUND_SUPPORTED
-/* Handle alpha and tRNS by replacing with a background color.  Prior to
- * libpng-1.5.4 this API must not be called before the PNG file header has been
- * read.  Doing so will result in unexpected behavior and possible warnings or
- * errors if the PNG file contains a bKGD chunk.
- */
-PNG_FP_EXPORT(47, void, png_set_background, (png_structp png_ptr,
-    png_const_color_16p background_color, int background_gamma_code,
-    int need_expand, double background_gamma))
-PNG_FIXED_EXPORT(215, void, png_set_background_fixed, (png_structp png_ptr,
-    png_const_color_16p background_color, int background_gamma_code,
-    int need_expand, png_fixed_point background_gamma))
-#endif
-#ifdef PNG_READ_BACKGROUND_SUPPORTED
-#  define PNG_BACKGROUND_GAMMA_UNKNOWN 0
-#  define PNG_BACKGROUND_GAMMA_SCREEN  1
-#  define PNG_BACKGROUND_GAMMA_FILE    2
-#  define PNG_BACKGROUND_GAMMA_UNIQUE  3
-#endif
-
-#ifdef PNG_READ_SCALE_16_TO_8_SUPPORTED
-/* Scale a 16-bit depth file down to 8-bit, accurately. */
-PNG_EXPORT(229, void, png_set_scale_16, (png_structp png_ptr));
-#endif
-
-#ifdef PNG_READ_STRIP_16_TO_8_SUPPORTED
-#define PNG_READ_16_TO_8 SUPPORTED /* Name prior to 1.5.4 */
-/* Strip the second byte of information from a 16-bit depth file. */
-PNG_EXPORT(48, void, png_set_strip_16, (png_structp png_ptr));
-#endif
-
-#ifdef PNG_READ_QUANTIZE_SUPPORTED
-/* Turn on quantizing, and reduce the palette to the number of colors
- * available.
- */
-PNG_EXPORT(49, void, png_set_quantize,
-    (png_structp png_ptr, png_colorp palette,
-    int num_palette, int maximum_colors, png_const_uint_16p histogram,
-    int full_quantize));
-#endif
-
-#ifdef PNG_READ_GAMMA_SUPPORTED
-/* The threshold on gamma processing is configurable but hard-wired into the
- * library.  The following is the floating point variant.
- */
-#define PNG_GAMMA_THRESHOLD (PNG_GAMMA_THRESHOLD_FIXED*.00001)
-
-/* Handle gamma correction. Screen_gamma=(display_exponent).
- * NOTE: this API simply sets the screen and file gamma values. It will
- * therefore override the value for gamma in a PNG file if it is called after
- * the file header has been read - use with care  - call before reading the PNG
- * file for best results!
- *
- * These routines accept the same gamma values as png_set_alpha_mode (described
- * above).  The PNG_GAMMA_ defines and PNG_DEFAULT_sRGB can be passed to either
- * API (floating point or fixed.)  Notice, however, that the 'file_gamma' value
- * is the inverse of a 'screen gamma' value.
- */
-PNG_FP_EXPORT(50, void, png_set_gamma,
-    (png_structp png_ptr, double screen_gamma,
-    double override_file_gamma))
-PNG_FIXED_EXPORT(208, void, png_set_gamma_fixed, (png_structp png_ptr,
-    png_fixed_point screen_gamma, png_fixed_point override_file_gamma))
-#endif
-
-#ifdef PNG_WRITE_FLUSH_SUPPORTED
-/* Set how many lines between output flushes - 0 for no flushing */
-PNG_EXPORT(51, void, png_set_flush, (png_structp png_ptr, int nrows));
-/* Flush the current PNG output buffer */
-PNG_EXPORT(52, void, png_write_flush, (png_structp png_ptr));
-#endif
-
-/* Optional update palette with requested transformations */
-PNG_EXPORT(53, void, png_start_read_image, (png_structp png_ptr));
-
-/* Optional call to update the users info structure */
-PNG_EXPORT(54, void, dg_png_read_update_info,
-    (png_structp png_ptr, png_infop info_ptr));
-
-#ifdef PNG_SEQUENTIAL_READ_SUPPORTED
-/* Read one or more rows of image data. */
-PNG_EXPORT(55, void, png_read_rows, (png_structp png_ptr, png_bytepp row,
-    png_bytepp display_row, png_uint_32 num_rows));
-#endif
-
-#ifdef PNG_SEQUENTIAL_READ_SUPPORTED
-/* Read a row of data. */
-PNG_EXPORT(56, void, png_read_row, (png_structp png_ptr, png_bytep row,
-    png_bytep display_row));
-#endif
-
-#ifdef PNG_SEQUENTIAL_READ_SUPPORTED
-/* Read the whole image into memory at once. */
-PNG_EXPORT(57, void, dg_png_read_image, (png_structp png_ptr, png_bytepp image));
-#endif
-
-/* Write a row of image data */
-PNG_EXPORT(58, void, png_write_row,
-    (png_structp png_ptr, png_const_bytep row));
-
-/* Write a few rows of image data: (*row) is not written; however, the type
- * is declared as writeable to maintain compatibility with previous versions
- * of libpng and to allow the 'display_row' array from read_rows to be passed
- * unchanged to write_rows.
- */
-PNG_EXPORT(59, void, png_write_rows, (png_structp png_ptr, png_bytepp row,
-    png_uint_32 num_rows));
-
-/* Write the image data */
-PNG_EXPORT(60, void, png_write_image,
-    (png_structp png_ptr, png_bytepp image));
-
-/* Write the end of the PNG file. */
-PNG_EXPORT(61, void, png_write_end,
-    (png_structp png_ptr, png_infop info_ptr));
-
-#ifdef PNG_SEQUENTIAL_READ_SUPPORTED
-/* Read the end of the PNG file. */
-PNG_EXPORT(62, void, png_read_end, (png_structp png_ptr, png_infop info_ptr));
-#endif
-
-/* Free any memory associated with the png_info_struct */
-PNG_EXPORT(63, void, png_destroy_info_struct, (png_structp png_ptr,
-    png_infopp info_ptr_ptr));
-
-/* Free any memory associated with the png_struct and the png_info_structs */
-PNG_EXPORT(64, void, dg_png_destroy_read_struct, (png_structpp png_ptr_ptr,
-    png_infopp info_ptr_ptr, png_infopp end_info_ptr_ptr));
-
-/* Free any memory associated with the png_struct and the png_info_structs */
-PNG_EXPORT(65, void, png_destroy_write_struct, (png_structpp png_ptr_ptr,
-    png_infopp info_ptr_ptr));
-
-/* Set the libpng method of handling chunk CRC errors */
-PNG_EXPORT(66, void, png_set_crc_action,
-    (png_structp png_ptr, int crit_action, int ancil_action));
-
-/* Values for png_set_crc_action() say how to handle CRC errors in
- * ancillary and critical chunks, and whether to use the data contained
- * therein.  Note that it is impossible to "discard" data in a critical
- * chunk.  For versions prior to 0.90, the action was always error/quit,
- * whereas in version 0.90 and later, the action for CRC errors in ancillary
- * chunks is warn/discard.  These values should NOT be changed.
- *
- *      value                       action:critical     action:ancillary
- */
-#define PNG_CRC_DEFAULT       0  /* error/quit          warn/discard data */
-#define PNG_CRC_ERROR_QUIT    1  /* error/quit          error/quit        */
-#define PNG_CRC_WARN_DISCARD  2  /* (INVALID)           warn/discard data */
-#define PNG_CRC_WARN_USE      3  /* warn/use data       warn/use data     */
-#define PNG_CRC_QUIET_USE     4  /* quiet/use data      quiet/use data    */
-#define PNG_CRC_NO_CHANGE     5  /* use current value   use current value */
-
-/* These functions give the user control over the scan-line filtering in
- * libpng and the compression methods used by zlib.  These functions are
- * mainly useful for testing, as the defaults should work with most users.
- * Those users who are tight on memory or want faster performance at the
- * expense of compression can modify them.  See the compression library
- * header file (zlib.h) for an explination of the compression functions.
- */
-
-/* Set the filtering method(s) used by libpng.  Currently, the only valid
- * value for "method" is 0.
- */
-PNG_EXPORT(67, void, png_set_filter,
-    (png_structp png_ptr, int method, int filters));
-
-/* Flags for png_set_filter() to say which filters to use.  The flags
- * are chosen so that they don't conflict with real filter types
- * below, in case they are supplied instead of the #defined constants.
- * These values should NOT be changed.
- */
-#define PNG_NO_FILTERS     0x00
-#define PNG_FILTER_NONE    0x08
-#define PNG_FILTER_SUB     0x10
-#define PNG_FILTER_UP      0x20
-#define PNG_FILTER_AVG     0x40
-#define PNG_FILTER_PAETH   0x80
-#define PNG_ALL_FILTERS (PNG_FILTER_NONE | PNG_FILTER_SUB | PNG_FILTER_UP | \
-                         PNG_FILTER_AVG | PNG_FILTER_PAETH)
-
-/* Filter values (not flags) - used in pngwrite.c, pngwutil.c for now.
- * These defines should NOT be changed.
- */
-#define PNG_FILTER_VALUE_NONE  0
-#define PNG_FILTER_VALUE_SUB   1
-#define PNG_FILTER_VALUE_UP    2
-#define PNG_FILTER_VALUE_AVG   3
-#define PNG_FILTER_VALUE_PAETH 4
-#define PNG_FILTER_VALUE_LAST  5
-
-#ifdef PNG_WRITE_WEIGHTED_FILTER_SUPPORTED /* EXPERIMENTAL */
-/* The "heuristic_method" is given by one of the PNG_FILTER_HEURISTIC_
- * defines, either the default (minimum-sum-of-absolute-differences), or
- * the experimental method (weighted-minimum-sum-of-absolute-differences).
- *
- * Weights are factors >= 1.0, indicating how important it is to keep the
- * filter type consistent between rows.  Larger numbers mean the current
- * filter is that many times as likely to be the same as the "num_weights"
- * previous filters.  This is cumulative for each previous row with a weight.
- * There needs to be "num_weights" values in "filter_weights", or it can be
- * NULL if the weights aren't being specified.  Weights have no influence on
- * the selection of the first row filter.  Well chosen weights can (in theory)
- * improve the compression for a given image.
- *
- * Costs are factors >= 1.0 indicating the relative decoding costs of a
- * filter type.  Higher costs indicate more decoding expense, and are
- * therefore less likely to be selected over a filter with lower computational
- * costs.  There needs to be a value in "filter_costs" for each valid filter
- * type (given by PNG_FILTER_VALUE_LAST), or it can be NULL if you aren't
- * setting the costs.  Costs try to improve the speed of decompression without
- * unduly increasing the compressed image size.
- *
- * A negative weight or cost indicates the default value is to be used, and
- * values in the range [0.0, 1.0) indicate the value is to remain unchanged.
- * The default values for both weights and costs are currently 1.0, but may
- * change if good general weighting/cost heuristics can be found.  If both
- * the weights and costs are set to 1.0, this degenerates the WEIGHTED method
- * to the UNWEIGHTED method, but with added encoding time/computation.
- */
-PNG_FP_EXPORT(68, void, png_set_filter_heuristics, (png_structp png_ptr,
-    int heuristic_method, int num_weights, png_const_doublep filter_weights,
-    png_const_doublep filter_costs))
-PNG_FIXED_EXPORT(209, void, png_set_filter_heuristics_fixed,
-    (png_structp png_ptr,
-    int heuristic_method, int num_weights, png_const_fixed_point_p
-    filter_weights, png_const_fixed_point_p filter_costs))
-#endif /*  PNG_WRITE_WEIGHTED_FILTER_SUPPORTED */
-
-/* Heuristic used for row filter selection.  These defines should NOT be
- * changed.
- */
-#define PNG_FILTER_HEURISTIC_DEFAULT    0  /* Currently "UNWEIGHTED" */
-#define PNG_FILTER_HEURISTIC_UNWEIGHTED 1  /* Used by libpng < 0.95 */
-#define PNG_FILTER_HEURISTIC_WEIGHTED   2  /* Experimental feature */
-#define PNG_FILTER_HEURISTIC_LAST       3  /* Not a valid value */
-
-#ifdef PNG_WRITE_SUPPORTED
-/* Set the library compression level.  Currently, valid values range from
- * 0 - 9, corresponding directly to the zlib compression levels 0 - 9
- * (0 - no compression, 9 - "maximal" compression).  Note that tests have
- * shown that zlib compression levels 3-6 usually perform as well as level 9
- * for PNG images, and do considerably fewer caclulations.  In the future,
- * these values may not correspond directly to the zlib compression levels.
- */
-PNG_EXPORT(69, void, png_set_compression_level,
-    (png_structp png_ptr, int level));
-
-PNG_EXPORT(70, void, png_set_compression_mem_level, (png_structp png_ptr,
-    int mem_level));
-
-PNG_EXPORT(71, void, png_set_compression_strategy, (png_structp png_ptr,
-    int strategy));
-
-/* If PNG_WRITE_OPTIMIZE_CMF_SUPPORTED is defined, libpng will use a
- * smaller value of window_bits if it can do so safely.
- */
-PNG_EXPORT(72, void, png_set_compression_window_bits, (png_structp png_ptr,
-    int window_bits));
-
-PNG_EXPORT(73, void, png_set_compression_method, (png_structp png_ptr,
-    int method));
-#endif
-
-#ifdef PNG_WRITE_CUSTOMIZE_ZTXT_COMPRESSION_SUPPORTED
-/* Also set zlib parameters for compressing non-IDAT chunks */
-PNG_EXPORT(222, void, png_set_text_compression_level,
-    (png_structp png_ptr, int level));
-
-PNG_EXPORT(223, void, png_set_text_compression_mem_level, (png_structp png_ptr,
-    int mem_level));
-
-PNG_EXPORT(224, void, png_set_text_compression_strategy, (png_structp png_ptr,
-    int strategy));
-
-/* If PNG_WRITE_OPTIMIZE_CMF_SUPPORTED is defined, libpng will use a
- * smaller value of window_bits if it can do so safely.
- */
-PNG_EXPORT(225, void, png_set_text_compression_window_bits, (png_structp
-    png_ptr, int window_bits));
-
-PNG_EXPORT(226, void, png_set_text_compression_method, (png_structp png_ptr,
-    int method));
-#endif /* PNG_WRITE_CUSTOMIZE_ZTXT_COMPRESSION_SUPPORTED */
-
-/* These next functions are called for input/output, memory, and error
- * handling.  They are in the file pngrio.c, pngwio.c, and pngerror.c,
- * and call standard C I/O routines such as fread(), fwrite(), and
- * fprintf().  These functions can be made to use other I/O routines
- * at run time for those applications that need to handle I/O in a
- * different manner by calling png_set_???_fn().  See libpng-manual.txt for
- * more information.
- */
-
-#ifdef PNG_STDIO_SUPPORTED
-/* Initialize the input/output for the PNG file to the default functions. */
-PNG_EXPORT(74, void, png_init_io, (png_structp png_ptr, png_FILE_p fp));
-#endif
-
-/* Replace the (error and abort), and warning functions with user
- * supplied functions.  If no messages are to be printed you must still
- * write and use replacement functions. The replacement error_fn should
- * still do a longjmp to the last setjmp location if you are using this
- * method of error handling.  If error_fn or warning_fn is NULL, the
- * default function will be used.
- */
-
-PNG_EXPORT(75, void, png_set_error_fn,
-    (png_structp png_ptr, png_voidp error_ptr,
-    png_error_ptr error_fn, png_error_ptr warning_fn));
-
-/* Return the user pointer associated with the error functions */
-PNG_EXPORT(76, png_voidp, png_get_error_ptr, (png_const_structp png_ptr));
-
-/* Replace the default data output functions with a user supplied one(s).
- * If buffered output is not used, then output_flush_fn can be set to NULL.
- * If PNG_WRITE_FLUSH_SUPPORTED is not defined at libpng compile time
- * output_flush_fn will be ignored (and thus can be NULL).
- * It is probably a mistake to use NULL for output_flush_fn if
- * write_data_fn is not also NULL unless you have built libpng with
- * PNG_WRITE_FLUSH_SUPPORTED undefined, because in this case libpng's
- * default flush function, which uses the standard *FILE structure, will
- * be used.
- */
-PNG_EXPORT(77, void, png_set_write_fn, (png_structp png_ptr, png_voidp io_ptr,
-    png_rw_ptr write_data_fn, png_flush_ptr output_flush_fn));
-
-/* Replace the default data input function with a user supplied one. */
-PNG_EXPORT(78, void, dg_png_set_read_fn, (png_structp png_ptr, png_voidp io_ptr,
-    png_rw_ptr read_data_fn));
-
-/* Return the user pointer associated with the I/O functions */
-PNG_EXPORT(79, png_voidp, dg_png_get_io_ptr, (png_structp png_ptr));
-
-PNG_EXPORT(80, void, png_set_read_status_fn, (png_structp png_ptr,
-    png_read_status_ptr read_row_fn));
-
-PNG_EXPORT(81, void, png_set_write_status_fn, (png_structp png_ptr,
-    png_write_status_ptr write_row_fn));
-
-#ifdef PNG_USER_MEM_SUPPORTED
-/* Replace the default memory allocation functions with user supplied one(s). */
-PNG_EXPORT(82, void, png_set_mem_fn, (png_structp png_ptr, png_voidp mem_ptr,
-    png_malloc_ptr malloc_fn, png_free_ptr free_fn));
-/* Return the user pointer associated with the memory functions */
-PNG_EXPORT(83, png_voidp, png_get_mem_ptr, (png_const_structp png_ptr));
-#endif
-
-#ifdef PNG_READ_USER_TRANSFORM_SUPPORTED
-PNG_EXPORT(84, void, png_set_read_user_transform_fn, (png_structp png_ptr,
-    png_user_transform_ptr read_user_transform_fn));
-#endif
-
-#ifdef PNG_WRITE_USER_TRANSFORM_SUPPORTED
-PNG_EXPORT(85, void, png_set_write_user_transform_fn, (png_structp png_ptr,
-    png_user_transform_ptr write_user_transform_fn));
-#endif
-
-#ifdef PNG_USER_TRANSFORM_PTR_SUPPORTED
-PNG_EXPORT(86, void, png_set_user_transform_info, (png_structp png_ptr,
-    png_voidp user_transform_ptr, int user_transform_depth,
-    int user_transform_channels));
-/* Return the user pointer associated with the user transform functions */
-PNG_EXPORT(87, png_voidp, png_get_user_transform_ptr,
-    (png_const_structp png_ptr));
-#endif
-
-#ifdef PNG_USER_TRANSFORM_INFO_SUPPORTED
-/* Return information about the row currently being processed.  Note that these
- * APIs do not fail but will return unexpected results if called outside a user
- * transform callback.  Also note that when transforming an interlaced image the
- * row number is the row number within the sub-image of the interlace pass, so
- * the value will increase to the height of the sub-image (not the full image)
- * then reset to 0 for the next pass.
- *
- * Use PNG_ROW_FROM_PASS_ROW(row, pass) and PNG_COL_FROM_PASS_COL(col, pass) to
- * find the output pixel (x,y) given an interlaced sub-image pixel
- * (row,col,pass).  (See below for these macros.)
- */
-PNG_EXPORT(217, png_uint_32, png_get_current_row_number, (png_const_structp));
-PNG_EXPORT(218, png_byte, png_get_current_pass_number, (png_const_structp));
-#endif
-
-#ifdef PNG_USER_CHUNKS_SUPPORTED
-PNG_EXPORT(88, void, png_set_read_user_chunk_fn, (png_structp png_ptr,
-    png_voidp user_chunk_ptr, png_user_chunk_ptr read_user_chunk_fn));
-PNG_EXPORT(89, png_voidp, png_get_user_chunk_ptr, (png_const_structp png_ptr));
-#endif
-
-#ifdef PNG_PROGRESSIVE_READ_SUPPORTED
-/* Sets the function callbacks for the push reader, and a pointer to a
- * user-defined structure available to the callback functions.
- */
-PNG_EXPORT(90, void, png_set_progressive_read_fn, (png_structp png_ptr,
-    png_voidp progressive_ptr, png_progressive_info_ptr info_fn,
-    png_progressive_row_ptr row_fn, png_progressive_end_ptr end_fn));
-
-/* Returns the user pointer associated with the push read functions */
-PNG_EXPORT(91, png_voidp, png_get_progressive_ptr, (png_const_structp png_ptr));
-
-/* Function to be called when data becomes available */
-PNG_EXPORT(92, void, png_process_data,
-    (png_structp png_ptr, png_infop info_ptr,
-    png_bytep buffer, png_size_t buffer_size));
-
-/* A function which may be called *only* within png_process_data to stop the
- * processing of any more data.  The function returns the number of bytes
- * remaining, excluding any that libpng has cached internally.  A subsequent
- * call to png_process_data must supply these bytes again.  If the argument
- * 'save' is set to true the routine will first save all the pending data and
- * will always return 0.
- */
-PNG_EXPORT(219, png_size_t, png_process_data_pause, (png_structp, int save));
-
-/* A function which may be called *only* outside (after) a call to
- * png_process_data.  It returns the number of bytes of data to skip in the
- * input.  Normally it will return 0, but if it returns a non-zero value the
- * application must skip than number of bytes of input data and pass the
- * following data to the next call to png_process_data.
- */
-PNG_EXPORT(220, png_uint_32, png_process_data_skip, (png_structp));
-
-#ifdef PNG_READ_INTERLACING_SUPPORTED
-/* Function that combines rows.  'new_row' is a flag that should come from
- * the callback and be non-NULL if anything needs to be done; the library
- * stores its own version of the new data internally and ignores the passed
- * in value.
- */
-PNG_EXPORT(93, void, png_progressive_combine_row, (png_structp png_ptr,
-    png_bytep old_row, png_const_bytep new_row));
-#endif /* PNG_READ_INTERLACING_SUPPORTED */
-#endif /* PNG_PROGRESSIVE_READ_SUPPORTED */
-
-PNG_EXPORTA(94, png_voidp, png_malloc,
-    (png_structp png_ptr, png_alloc_size_t size),
-    PNG_ALLOCATED);
-/* Added at libpng version 1.4.0 */
-PNG_EXPORTA(95, png_voidp, png_calloc,
-    (png_structp png_ptr, png_alloc_size_t size),
-    PNG_ALLOCATED);
-
-/* Added at libpng version 1.2.4 */
-PNG_EXPORTA(96, png_voidp, png_malloc_warn, (png_structp png_ptr,
-    png_alloc_size_t size), PNG_ALLOCATED);
-
-/* Frees a pointer allocated by png_malloc() */
-PNG_EXPORT(97, void, png_free, (png_structp png_ptr, png_voidp ptr));
-
-/* Free data that was allocated internally */
-PNG_EXPORT(98, void, png_free_data,
-    (png_structp png_ptr, png_infop info_ptr, png_uint_32 free_me, int num));
-
-/* Reassign responsibility for freeing existing data, whether allocated
- * by libpng or by the application */
-PNG_EXPORT(99, void, png_data_freer,
-    (png_structp png_ptr, png_infop info_ptr, int freer, png_uint_32 mask));
-
-/* Assignments for png_data_freer */
-#define PNG_DESTROY_WILL_FREE_DATA 1
-#define PNG_SET_WILL_FREE_DATA 1
-#define PNG_USER_WILL_FREE_DATA 2
-/* Flags for png_ptr->free_me and info_ptr->free_me */
-#define PNG_FREE_HIST 0x0008
-#define PNG_FREE_ICCP 0x0010
-#define PNG_FREE_SPLT 0x0020
-#define PNG_FREE_ROWS 0x0040
-#define PNG_FREE_PCAL 0x0080
-#define PNG_FREE_SCAL 0x0100
-#define PNG_FREE_UNKN 0x0200
-#define PNG_FREE_LIST 0x0400
-#define PNG_FREE_PLTE 0x1000
-#define PNG_FREE_TRNS 0x2000
-#define PNG_FREE_TEXT 0x4000
-#define PNG_FREE_ALL  0x7fff
-#define PNG_FREE_MUL  0x4220 /* PNG_FREE_SPLT|PNG_FREE_TEXT|PNG_FREE_UNKN */
-
-#ifdef PNG_USER_MEM_SUPPORTED
-PNG_EXPORTA(100, png_voidp, png_malloc_default, (png_structp png_ptr,
-    png_alloc_size_t size), PNG_ALLOCATED);
-PNG_EXPORT(101, void, png_free_default, (png_structp png_ptr, png_voidp ptr));
-#endif
-
-#ifdef PNG_ERROR_TEXT_SUPPORTED
-/* Fatal error in PNG image of libpng - can't continue */
-PNG_EXPORTA(102, void, dg_png_error,
-    (png_structp png_ptr, png_const_charp error_message),
-    PNG_NORETURN);
-
-/* The same, but the chunk name is prepended to the error string. */
-PNG_EXPORTA(103, void, png_chunk_error, (png_structp png_ptr,
-    png_const_charp error_message), PNG_NORETURN);
-
-#else
-/* Fatal error in PNG image of libpng - can't continue */
-PNG_EXPORTA(104, void, png_err, (png_structp png_ptr), PNG_NORETURN);
-#endif
-
-#ifdef PNG_WARNINGS_SUPPORTED
-/* Non-fatal error in libpng.  Can continue, but may have a problem. */
-PNG_EXPORT(105, void, png_warning, (png_structp png_ptr,
-    png_const_charp warning_message));
-
-/* Non-fatal error in libpng, chunk name is prepended to message. */
-PNG_EXPORT(106, void, png_chunk_warning, (png_structp png_ptr,
-    png_const_charp warning_message));
-#endif
-
-#ifdef PNG_BENIGN_ERRORS_SUPPORTED
-/* Benign error in libpng.  Can continue, but may have a problem.
- * User can choose whether to handle as a fatal error or as a warning. */
-#  undef png_benign_error
-PNG_EXPORT(107, void, png_benign_error, (png_structp png_ptr,
-    png_const_charp warning_message));
-
-/* Same, chunk name is prepended to message. */
-#  undef png_chunk_benign_error
-PNG_EXPORT(108, void, png_chunk_benign_error, (png_structp png_ptr,
-    png_const_charp warning_message));
-
-PNG_EXPORT(109, void, png_set_benign_errors,
-    (png_structp png_ptr, int allowed));
-#else
-#  ifdef PNG_ALLOW_BENIGN_ERRORS
-#    define png_benign_error png_warning
-#    define png_chunk_benign_error png_chunk_warning
-#  else
-#    define png_benign_error png_error
-#    define png_chunk_benign_error png_chunk_error
-#  endif
-#endif
-
-/* The png_set_<chunk> functions are for storing values in the png_info_struct.
- * Similarly, the png_get_<chunk> calls are used to read values from the
- * png_info_struct, either storing the parameters in the passed variables, or
- * setting pointers into the png_info_struct where the data is stored.  The
- * png_get_<chunk> functions return a non-zero value if the data was available
- * in info_ptr, or return zero and do not change any of the parameters if the
- * data was not available.
- *
- * These functions should be used instead of directly accessing png_info
- * to avoid problems with future changes in the size and internal layout of
- * png_info_struct.
- */
-/* Returns "flag" if chunk data is valid in info_ptr. */
-PNG_EXPORT(110, png_uint_32, png_get_valid,
-    (png_const_structp png_ptr, png_const_infop info_ptr,
-    png_uint_32 flag));
-
-/* Returns number of bytes needed to hold a transformed row. */
-PNG_EXPORT(111, png_size_t, dg_png_get_rowbytes, (png_const_structp png_ptr,
-    png_const_infop info_ptr));
-
-#ifdef PNG_INFO_IMAGE_SUPPORTED
-/* Returns row_pointers, which is an array of pointers to scanlines that was
- * returned from png_read_png().
- */
-PNG_EXPORT(112, png_bytepp, png_get_rows,
-    (png_const_structp png_ptr, png_const_infop info_ptr));
-/* Set row_pointers, which is an array of pointers to scanlines for use
- * by png_write_png().
- */
-PNG_EXPORT(113, void, png_set_rows, (png_structp png_ptr,
-    png_infop info_ptr, png_bytepp row_pointers));
-#endif
-
-/* Returns number of color channels in image. */
-PNG_EXPORT(114, png_byte, png_get_channels,
-    (png_const_structp png_ptr, png_const_infop info_ptr));
-
-#ifdef PNG_EASY_ACCESS_SUPPORTED
-/* Returns image width in pixels. */
-PNG_EXPORT(115, png_uint_32, dg_png_get_image_width, (png_const_structp png_ptr,
-    png_const_infop info_ptr));
-
-/* Returns image height in pixels. */
-PNG_EXPORT(116, png_uint_32, dg_png_get_image_height, (png_const_structp png_ptr,
-    png_const_infop info_ptr));
-
-/* Returns image bit_depth. */
-PNG_EXPORT(117, png_byte, png_get_bit_depth,
-    (png_const_structp png_ptr, png_const_infop info_ptr));
-
-/* Returns image color_type. */
-PNG_EXPORT(118, png_byte, png_get_color_type, (png_const_structp png_ptr,
-    png_const_infop info_ptr));
-
-/* Returns image filter_type. */
-PNG_EXPORT(119, png_byte, png_get_filter_type, (png_const_structp png_ptr,
-    png_const_infop info_ptr));
-
-/* Returns image interlace_type. */
-PNG_EXPORT(120, png_byte, png_get_interlace_type, (png_const_structp png_ptr,
-    png_const_infop info_ptr));
-
-/* Returns image compression_type. */
-PNG_EXPORT(121, png_byte, png_get_compression_type, (png_const_structp png_ptr,
-    png_const_infop info_ptr));
-
-/* Returns image resolution in pixels per meter, from pHYs chunk data. */
-PNG_EXPORT(122, png_uint_32, png_get_pixels_per_meter,
-    (png_const_structp png_ptr, png_const_infop info_ptr));
-PNG_EXPORT(123, png_uint_32, png_get_x_pixels_per_meter,
-    (png_const_structp png_ptr, png_const_infop info_ptr));
-PNG_EXPORT(124, png_uint_32, png_get_y_pixels_per_meter,
-    (png_const_structp png_ptr, png_const_infop info_ptr));
-
-/* Returns pixel aspect ratio, computed from pHYs chunk data.  */
-PNG_FP_EXPORT(125, float, png_get_pixel_aspect_ratio,
-    (png_const_structp png_ptr, png_const_infop info_ptr))
-PNG_FIXED_EXPORT(210, png_fixed_point, png_get_pixel_aspect_ratio_fixed,
-    (png_const_structp png_ptr, png_const_infop info_ptr))
-
-/* Returns image x, y offset in pixels or microns, from oFFs chunk data. */
-PNG_EXPORT(126, png_int_32, png_get_x_offset_pixels,
-    (png_const_structp png_ptr, png_const_infop info_ptr));
-PNG_EXPORT(127, png_int_32, png_get_y_offset_pixels,
-    (png_const_structp png_ptr, png_const_infop info_ptr));
-PNG_EXPORT(128, png_int_32, png_get_x_offset_microns,
-    (png_const_structp png_ptr, png_const_infop info_ptr));
-PNG_EXPORT(129, png_int_32, png_get_y_offset_microns,
-    (png_const_structp png_ptr, png_const_infop info_ptr));
-
-#endif /* PNG_EASY_ACCESS_SUPPORTED */
-
-/* Returns pointer to signature string read from PNG header */
-PNG_EXPORT(130, png_const_bytep, png_get_signature,
-    (png_const_structp png_ptr, png_infop info_ptr));
-
-#ifdef PNG_bKGD_SUPPORTED
-PNG_EXPORT(131, png_uint_32, png_get_bKGD,
-    (png_const_structp png_ptr, png_infop info_ptr,
-    png_color_16p *background));
-#endif
-
-#ifdef PNG_bKGD_SUPPORTED
-PNG_EXPORT(132, void, png_set_bKGD, (png_structp png_ptr, png_infop info_ptr,
-    png_const_color_16p background));
-#endif
-
-#ifdef PNG_cHRM_SUPPORTED
-PNG_FP_EXPORT(133, png_uint_32, png_get_cHRM, (png_const_structp png_ptr,
-   png_const_infop info_ptr, double *white_x, double *white_y, double *red_x,
-    double *red_y, double *green_x, double *green_y, double *blue_x,
-    double *blue_y))
-PNG_FP_EXPORT(230, png_uint_32, png_get_cHRM_XYZ, (png_structp png_ptr,
-    png_const_infop info_ptr, double *red_X, double *red_Y, double *red_Z,
-    double *green_X, double *green_Y, double *green_Z, double *blue_X,
-    double *blue_Y, double *blue_Z))
-#ifdef PNG_FIXED_POINT_SUPPORTED /* Otherwise not implemented */
-PNG_FIXED_EXPORT(134, png_uint_32, png_get_cHRM_fixed,
-    (png_const_structp png_ptr,
-    png_const_infop info_ptr, png_fixed_point *int_white_x,
-    png_fixed_point *int_white_y, png_fixed_point *int_red_x,
-    png_fixed_point *int_red_y, png_fixed_point *int_green_x,
-    png_fixed_point *int_green_y, png_fixed_point *int_blue_x,
-    png_fixed_point *int_blue_y))
-#endif
-PNG_FIXED_EXPORT(231, png_uint_32, png_get_cHRM_XYZ_fixed,
-    (png_structp png_ptr, png_const_infop info_ptr,
-    png_fixed_point *int_red_X, png_fixed_point *int_red_Y,
-    png_fixed_point *int_red_Z, png_fixed_point *int_green_X,
-    png_fixed_point *int_green_Y, png_fixed_point *int_green_Z,
-    png_fixed_point *int_blue_X, png_fixed_point *int_blue_Y,
-    png_fixed_point *int_blue_Z))
-#endif
-
-#ifdef PNG_cHRM_SUPPORTED
-PNG_FP_EXPORT(135, void, png_set_cHRM,
-    (png_structp png_ptr, png_infop info_ptr,
-    double white_x, double white_y, double red_x, double red_y, double green_x,
-    double green_y, double blue_x, double blue_y))
-PNG_FP_EXPORT(232, void, png_set_cHRM_XYZ, (png_structp png_ptr,
-    png_infop info_ptr, double red_X, double red_Y, double red_Z,
-    double green_X, double green_Y, double green_Z, double blue_X,
-    double blue_Y, double blue_Z))
-PNG_FIXED_EXPORT(136, void, png_set_cHRM_fixed, (png_structp png_ptr,
-    png_infop info_ptr, png_fixed_point int_white_x,
-    png_fixed_point int_white_y, png_fixed_point int_red_x,
-    png_fixed_point int_red_y, png_fixed_point int_green_x,
-    png_fixed_point int_green_y, png_fixed_point int_blue_x,
-    png_fixed_point int_blue_y))
-PNG_FIXED_EXPORT(233, void, png_set_cHRM_XYZ_fixed, (png_structp png_ptr,
-    png_infop info_ptr, png_fixed_point int_red_X, png_fixed_point int_red_Y,
-    png_fixed_point int_red_Z, png_fixed_point int_green_X,
-    png_fixed_point int_green_Y, png_fixed_point int_green_Z,
-    png_fixed_point int_blue_X, png_fixed_point int_blue_Y,
-    png_fixed_point int_blue_Z))
-#endif
-
-#ifdef PNG_gAMA_SUPPORTED
-PNG_FP_EXPORT(137, png_uint_32, png_get_gAMA,
-    (png_const_structp png_ptr, png_const_infop info_ptr,
-    double *file_gamma))
-PNG_FIXED_EXPORT(138, png_uint_32, png_get_gAMA_fixed,
-    (png_const_structp png_ptr, png_const_infop info_ptr,
-    png_fixed_point *int_file_gamma))
-#endif
-
-#ifdef PNG_gAMA_SUPPORTED
-PNG_FP_EXPORT(139, void, png_set_gAMA, (png_structp png_ptr,
-    png_infop info_ptr, double file_gamma))
-PNG_FIXED_EXPORT(140, void, png_set_gAMA_fixed, (png_structp png_ptr,
-    png_infop info_ptr, png_fixed_point int_file_gamma))
-#endif
-
-#ifdef PNG_hIST_SUPPORTED
-PNG_EXPORT(141, png_uint_32, png_get_hIST,
-    (png_const_structp png_ptr, png_const_infop info_ptr,
-    png_uint_16p *hist));
-#endif
-
-#ifdef PNG_hIST_SUPPORTED
-PNG_EXPORT(142, void, png_set_hIST, (png_structp png_ptr,
-    png_infop info_ptr, png_const_uint_16p hist));
-#endif
-
-PNG_EXPORT(143, png_uint_32, png_get_IHDR,
-    (png_structp png_ptr, png_infop info_ptr,
-    png_uint_32 *width, png_uint_32 *height, int *bit_depth, int *color_type,
-    int *interlace_method, int *compression_method, int *filter_method));
-
-PNG_EXPORT(144, void, png_set_IHDR,
-    (png_structp png_ptr, png_infop info_ptr,
-    png_uint_32 width, png_uint_32 height, int bit_depth, int color_type,
-    int interlace_method, int compression_method, int filter_method));
-
-#ifdef PNG_oFFs_SUPPORTED
-PNG_EXPORT(145, png_uint_32, png_get_oFFs,
-    (png_const_structp png_ptr, png_const_infop info_ptr,
-    png_int_32 *offset_x, png_int_32 *offset_y, int *unit_type));
-#endif
-
-#ifdef PNG_oFFs_SUPPORTED
-PNG_EXPORT(146, void, png_set_oFFs,
-    (png_structp png_ptr, png_infop info_ptr,
-    png_int_32 offset_x, png_int_32 offset_y, int unit_type));
-#endif
-
-#ifdef PNG_pCAL_SUPPORTED
-PNG_EXPORT(147, png_uint_32, png_get_pCAL,
-    (png_const_structp png_ptr, png_const_infop info_ptr,
-    png_charp *purpose, png_int_32 *X0, png_int_32 *X1, int *type,
-    int *nparams,
-    png_charp *units, png_charpp *params));
-#endif
-
-#ifdef PNG_pCAL_SUPPORTED
-PNG_EXPORT(148, void, png_set_pCAL, (png_structp png_ptr,
-    png_infop info_ptr,
-    png_const_charp purpose, png_int_32 X0, png_int_32 X1, int type,
-    int nparams, png_const_charp units, png_charpp params));
-#endif
-
-#ifdef PNG_pHYs_SUPPORTED
-PNG_EXPORT(149, png_uint_32, png_get_pHYs,
-    (png_const_structp png_ptr, png_const_infop info_ptr,
-    png_uint_32 *res_x, png_uint_32 *res_y, int *unit_type));
-#endif
-
-#ifdef PNG_pHYs_SUPPORTED
-PNG_EXPORT(150, void, png_set_pHYs,
-    (png_structp png_ptr, png_infop info_ptr,
-    png_uint_32 res_x, png_uint_32 res_y, int unit_type));
-#endif
-
-PNG_EXPORT(151, png_uint_32, png_get_PLTE,
-    (png_const_structp png_ptr, png_const_infop info_ptr,
-    png_colorp *palette, int *num_palette));
-
-PNG_EXPORT(152, void, png_set_PLTE,
-    (png_structp png_ptr, png_infop info_ptr,
-    png_const_colorp palette, int num_palette));
-
-#ifdef PNG_sBIT_SUPPORTED
-PNG_EXPORT(153, png_uint_32, png_get_sBIT,
-    (png_const_structp png_ptr, png_infop info_ptr,
-    png_color_8p *sig_bit));
-#endif
-
-#ifdef PNG_sBIT_SUPPORTED
-PNG_EXPORT(154, void, png_set_sBIT,
-    (png_structp png_ptr, png_infop info_ptr, png_const_color_8p sig_bit));
-#endif
-
-#ifdef PNG_sRGB_SUPPORTED
-PNG_EXPORT(155, png_uint_32, png_get_sRGB, (png_const_structp png_ptr,
-    png_const_infop info_ptr, int *file_srgb_intent));
-#endif
-
-#ifdef PNG_sRGB_SUPPORTED
-PNG_EXPORT(156, void, png_set_sRGB,
-    (png_structp png_ptr, png_infop info_ptr, int srgb_intent));
-PNG_EXPORT(157, void, png_set_sRGB_gAMA_and_cHRM, (png_structp png_ptr,
-    png_infop info_ptr, int srgb_intent));
-#endif
-
-#ifdef PNG_iCCP_SUPPORTED
-PNG_EXPORT(158, png_uint_32, png_get_iCCP,
-    (png_const_structp png_ptr, png_const_infop info_ptr,
-    png_charpp name, int *compression_type, png_bytepp profile,
-    png_uint_32 *proflen));
-#endif
-
-#ifdef PNG_iCCP_SUPPORTED
-PNG_EXPORT(159, void, png_set_iCCP,
-    (png_structp png_ptr, png_infop info_ptr,
-    png_const_charp name, int compression_type, png_const_bytep profile,
-    png_uint_32 proflen));
-#endif
-
-#ifdef PNG_sPLT_SUPPORTED
-PNG_EXPORT(160, png_uint_32, png_get_sPLT,
-    (png_const_structp png_ptr, png_const_infop info_ptr,
-    png_sPLT_tpp entries));
-#endif
-
-#ifdef PNG_sPLT_SUPPORTED
-PNG_EXPORT(161, void, png_set_sPLT,
-    (png_structp png_ptr, png_infop info_ptr,
-    png_const_sPLT_tp entries, int nentries));
-#endif
-
-#ifdef PNG_TEXT_SUPPORTED
-/* png_get_text also returns the number of text chunks in *num_text */
-PNG_EXPORT(162, png_uint_32, png_get_text,
-    (png_const_structp png_ptr, png_const_infop info_ptr,
-    png_textp *text_ptr, int *num_text));
-#endif
-
-/* Note while png_set_text() will accept a structure whose text,
- * language, and  translated keywords are NULL pointers, the structure
- * returned by png_get_text will always contain regular
- * zero-terminated C strings.  They might be empty strings but
- * they will never be NULL pointers.
- */
-
-#ifdef PNG_TEXT_SUPPORTED
-PNG_EXPORT(163, void, png_set_text,
-    (png_structp png_ptr, png_infop info_ptr,
-    png_const_textp text_ptr, int num_text));
-#endif
-
-#ifdef PNG_tIME_SUPPORTED
-PNG_EXPORT(164, png_uint_32, png_get_tIME,
-    (png_const_structp png_ptr, png_infop info_ptr, png_timep *mod_time));
-#endif
-
-#ifdef PNG_tIME_SUPPORTED
-PNG_EXPORT(165, void, png_set_tIME,
-    (png_structp png_ptr, png_infop info_ptr, png_const_timep mod_time));
-#endif
-
-#ifdef PNG_tRNS_SUPPORTED
-PNG_EXPORT(166, png_uint_32, png_get_tRNS,
-    (png_const_structp png_ptr, png_infop info_ptr,
-    png_bytep *trans_alpha, int *num_trans, png_color_16p *trans_color));
-#endif
-
-#ifdef PNG_tRNS_SUPPORTED
-PNG_EXPORT(167, void, png_set_tRNS,
-    (png_structp png_ptr, png_infop info_ptr,
-    png_const_bytep trans_alpha, int num_trans,
-    png_const_color_16p trans_color));
-#endif
-
-#ifdef PNG_sCAL_SUPPORTED
-PNG_FP_EXPORT(168, png_uint_32, png_get_sCAL,
-    (png_const_structp png_ptr, png_const_infop info_ptr,
-    int *unit, double *width, double *height))
-#ifdef PNG_FLOATING_ARITHMETIC_SUPPORTED
-/* NOTE: this API is currently implemented using floating point arithmetic,
- * consequently it can only be used on systems with floating point support.
- * In any case the range of values supported by png_fixed_point is small and it
- * is highly recommended that png_get_sCAL_s be used instead.
- */
-PNG_FIXED_EXPORT(214, png_uint_32, png_get_sCAL_fixed,
-    (png_structp png_ptr, png_const_infop info_ptr, int *unit,
-    png_fixed_point *width,
-    png_fixed_point *height))
-#endif
-PNG_EXPORT(169, png_uint_32, png_get_sCAL_s,
-    (png_const_structp png_ptr, png_const_infop info_ptr,
-    int *unit, png_charpp swidth, png_charpp sheight));
-
-PNG_FP_EXPORT(170, void, png_set_sCAL,
-    (png_structp png_ptr, png_infop info_ptr,
-    int unit, double width, double height))
-PNG_FIXED_EXPORT(213, void, png_set_sCAL_fixed, (png_structp png_ptr,
-   png_infop info_ptr, int unit, png_fixed_point width,
-   png_fixed_point height))
-PNG_EXPORT(171, void, png_set_sCAL_s,
-    (png_structp png_ptr, png_infop info_ptr,
-    int unit, png_const_charp swidth, png_const_charp sheight));
-#endif /* PNG_sCAL_SUPPORTED */
-
-#ifdef PNG_HANDLE_AS_UNKNOWN_SUPPORTED
-/* Provide a list of chunks and how they are to be handled, if the built-in
-   handling or default unknown chunk handling is not desired.  Any chunks not
-   listed will be handled in the default manner.  The IHDR and IEND chunks
-   must not be listed.  Because this turns off the default handling for chunks
-   that would otherwise be recognized the behavior of libpng transformations may
-   well become incorrect!
-      keep = 0: PNG_HANDLE_CHUNK_AS_DEFAULT: follow default behavior
-           = 1: PNG_HANDLE_CHUNK_NEVER:      do not keep
-           = 2: PNG_HANDLE_CHUNK_IF_SAFE:    keep only if safe-to-copy
-           = 3: PNG_HANDLE_CHUNK_ALWAYS:     keep even if unsafe-to-copy
-*/
-PNG_EXPORT(172, void, png_set_keep_unknown_chunks,
-    (png_structp png_ptr, int keep,
-    png_const_bytep chunk_list, int num_chunks));
-
-/* The handling code is returned; the result is therefore true (non-zero) if
- * special handling is required, false for the default handling.
- */
-PNG_EXPORT(173, int, png_handle_as_unknown, (png_structp png_ptr,
-    png_const_bytep chunk_name));
-#endif
-#ifdef PNG_UNKNOWN_CHUNKS_SUPPORTED
-PNG_EXPORT(174, void, png_set_unknown_chunks, (png_structp png_ptr,
-    png_infop info_ptr, png_const_unknown_chunkp unknowns,
-    int num_unknowns));
-PNG_EXPORT(175, void, png_set_unknown_chunk_location,
-    (png_structp png_ptr, png_infop info_ptr, int chunk, int location));
-PNG_EXPORT(176, int, png_get_unknown_chunks, (png_const_structp png_ptr,
-    png_const_infop info_ptr, png_unknown_chunkpp entries));
-#endif
-
-/* Png_free_data() will turn off the "valid" flag for anything it frees.
- * If you need to turn it off for a chunk that your application has freed,
- * you can use png_set_invalid(png_ptr, info_ptr, PNG_INFO_CHNK);
- */
-PNG_EXPORT(177, void, png_set_invalid,
-    (png_structp png_ptr, png_infop info_ptr, int mask));
-
-#ifdef PNG_INFO_IMAGE_SUPPORTED
-/* The "params" pointer is currently not used and is for future expansion. */
-PNG_EXPORT(178, void, png_read_png, (png_structp png_ptr, png_infop info_ptr,
-    int transforms, png_voidp params));
-PNG_EXPORT(179, void, png_write_png, (png_structp png_ptr, png_infop info_ptr,
-    int transforms, png_voidp params));
-#endif
-
-PNG_EXPORT(180, png_const_charp, png_get_copyright,
-    (png_const_structp png_ptr));
-PNG_EXPORT(181, png_const_charp, png_get_header_ver,
-    (png_const_structp png_ptr));
-PNG_EXPORT(182, png_const_charp, png_get_header_version,
-    (png_const_structp png_ptr));
-PNG_EXPORT(183, png_const_charp, png_get_libpng_ver,
-    (png_const_structp png_ptr));
-
-#ifdef PNG_MNG_FEATURES_SUPPORTED
-PNG_EXPORT(184, png_uint_32, png_permit_mng_features, (png_structp png_ptr,
-    png_uint_32 mng_features_permitted));
-#endif
-
-/* For use in png_set_keep_unknown, added to version 1.2.6 */
-#define PNG_HANDLE_CHUNK_AS_DEFAULT   0
-#define PNG_HANDLE_CHUNK_NEVER        1
-#define PNG_HANDLE_CHUNK_IF_SAFE      2
-#define PNG_HANDLE_CHUNK_ALWAYS       3
-
-/* Strip the prepended error numbers ("#nnn ") from error and warning
- * messages before passing them to the error or warning handler.
- */
-#ifdef PNG_ERROR_NUMBERS_SUPPORTED
-PNG_EXPORT(185, void, png_set_strip_error_numbers,
-    (png_structp png_ptr,
-    png_uint_32 strip_mode));
-#endif
-
-/* Added in libpng-1.2.6 */
-#ifdef PNG_SET_USER_LIMITS_SUPPORTED
-PNG_EXPORT(186, void, png_set_user_limits, (png_structp png_ptr,
-    png_uint_32 user_width_max, png_uint_32 user_height_max));
-PNG_EXPORT(187, png_uint_32, png_get_user_width_max,
-    (png_const_structp png_ptr));
-PNG_EXPORT(188, png_uint_32, png_get_user_height_max,
-    (png_const_structp png_ptr));
-/* Added in libpng-1.4.0 */
-PNG_EXPORT(189, void, png_set_chunk_cache_max, (png_structp png_ptr,
-    png_uint_32 user_chunk_cache_max));
-PNG_EXPORT(190, png_uint_32, png_get_chunk_cache_max,
-    (png_const_structp png_ptr));
-/* Added in libpng-1.4.1 */
-PNG_EXPORT(191, void, png_set_chunk_malloc_max, (png_structp png_ptr,
-    png_alloc_size_t user_chunk_cache_max));
-PNG_EXPORT(192, png_alloc_size_t, png_get_chunk_malloc_max,
-    (png_const_structp png_ptr));
-#endif
-
-#if defined(PNG_INCH_CONVERSIONS_SUPPORTED)
-PNG_EXPORT(193, png_uint_32, png_get_pixels_per_inch,
-    (png_const_structp png_ptr, png_const_infop info_ptr));
-
-PNG_EXPORT(194, png_uint_32, png_get_x_pixels_per_inch,
-    (png_const_structp png_ptr, png_const_infop info_ptr));
-
-PNG_EXPORT(195, png_uint_32, png_get_y_pixels_per_inch,
-    (png_const_structp png_ptr, png_const_infop info_ptr));
-
-PNG_FP_EXPORT(196, float, png_get_x_offset_inches,
-    (png_const_structp png_ptr, png_const_infop info_ptr))
-#ifdef PNG_FIXED_POINT_SUPPORTED /* otherwise not implemented. */
-PNG_FIXED_EXPORT(211, png_fixed_point, png_get_x_offset_inches_fixed,
-    (png_structp png_ptr, png_const_infop info_ptr))
-#endif
-
-PNG_FP_EXPORT(197, float, png_get_y_offset_inches, (png_const_structp png_ptr,
-    png_const_infop info_ptr))
-#ifdef PNG_FIXED_POINT_SUPPORTED /* otherwise not implemented. */
-PNG_FIXED_EXPORT(212, png_fixed_point, png_get_y_offset_inches_fixed,
-    (png_structp png_ptr, png_const_infop info_ptr))
-#endif
-
-#  ifdef PNG_pHYs_SUPPORTED
-PNG_EXPORT(198, png_uint_32, png_get_pHYs_dpi, (png_const_structp png_ptr,
-    png_const_infop info_ptr, png_uint_32 *res_x, png_uint_32 *res_y,
-    int *unit_type));
-#  endif /* PNG_pHYs_SUPPORTED */
-#endif  /* PNG_INCH_CONVERSIONS_SUPPORTED */
-
-/* Added in libpng-1.4.0 */
-#ifdef PNG_IO_STATE_SUPPORTED
-PNG_EXPORT(199, png_uint_32, png_get_io_state, (png_structp png_ptr));
-
-PNG_EXPORTA(200, png_const_bytep, png_get_io_chunk_name,
-    (png_structp png_ptr), PNG_DEPRECATED);
-PNG_EXPORT(216, png_uint_32, png_get_io_chunk_type,
-    (png_const_structp png_ptr));
-
-/* The flags returned by png_get_io_state() are the following: */
-#  define PNG_IO_NONE        0x0000   /* no I/O at this moment */
-#  define PNG_IO_READING     0x0001   /* currently reading */
-#  define PNG_IO_WRITING     0x0002   /* currently writing */
-#  define PNG_IO_SIGNATURE   0x0010   /* currently at the file signature */
-#  define PNG_IO_CHUNK_HDR   0x0020   /* currently at the chunk header */
-#  define PNG_IO_CHUNK_DATA  0x0040   /* currently at the chunk data */
-#  define PNG_IO_CHUNK_CRC   0x0080   /* currently at the chunk crc */
-#  define PNG_IO_MASK_OP     0x000f   /* current operation: reading/writing */
-#  define PNG_IO_MASK_LOC    0x00f0   /* current location: sig/hdr/data/crc */
-#endif /* ?PNG_IO_STATE_SUPPORTED */
-
-/* Interlace support.  The following macros are always defined so that if
- * libpng interlace handling is turned off the macros may be used to handle
- * interlaced images within the application.
- */
-#define PNG_INTERLACE_ADAM7_PASSES 7
-
-/* Two macros to return the first row and first column of the original,
- * full, image which appears in a given pass.  'pass' is in the range 0
- * to 6 and the result is in the range 0 to 7.
- */
-#define PNG_PASS_START_ROW(pass) (((1&~(pass))<<(3-((pass)>>1)))&7)
-#define PNG_PASS_START_COL(pass) (((1& (pass))<<(3-(((pass)+1)>>1)))&7)
-
-/* A macro to return the offset between pixels in the output row for a pair of
- * pixels in the input - effectively the inverse of the 'COL_SHIFT' macro that
- * follows.  Note that ROW_OFFSET is the offset from one row to the next whereas
- * COL_OFFSET is from one column to the next, within a row.
- */
-#define PNG_PASS_ROW_OFFSET(pass) ((pass)>2?(8>>(((pass)-1)>>1)):8)
-#define PNG_PASS_COL_OFFSET(pass) (1<<((7-(pass))>>1))
-
-/* Two macros to help evaluate the number of rows or columns in each
- * pass.  This is expressed as a shift - effectively log2 of the number or
- * rows or columns in each 8x8 tile of the original image.
- */
-#define PNG_PASS_ROW_SHIFT(pass) ((pass)>2?(8-(pass))>>1:3)
-#define PNG_PASS_COL_SHIFT(pass) ((pass)>1?(7-(pass))>>1:3)
-
-/* Hence two macros to determine the number of rows or columns in a given
- * pass of an image given its height or width.  In fact these macros may
- * return non-zero even though the sub-image is empty, because the other
- * dimension may be empty for a small image.
- */
-#define PNG_PASS_ROWS(height, pass) (((height)+(((1<<PNG_PASS_ROW_SHIFT(pass))\
-   -1)-PNG_PASS_START_ROW(pass)))>>PNG_PASS_ROW_SHIFT(pass))
-#define PNG_PASS_COLS(width, pass) (((width)+(((1<<PNG_PASS_COL_SHIFT(pass))\
-   -1)-PNG_PASS_START_COL(pass)))>>PNG_PASS_COL_SHIFT(pass))
-
-/* For the reader row callbacks (both progressive and sequential) it is
- * necessary to find the row in the output image given a row in an interlaced
- * image, so two more macros:
- */
-#define PNG_ROW_FROM_PASS_ROW(yIn, pass) \
-   (((yIn)<<PNG_PASS_ROW_SHIFT(pass))+PNG_PASS_START_ROW(pass))
-#define PNG_COL_FROM_PASS_COL(xIn, pass) \
-   (((xIn)<<PNG_PASS_COL_SHIFT(pass))+PNG_PASS_START_COL(pass))
-
-/* Two macros which return a boolean (0 or 1) saying whether the given row
- * or column is in a particular pass.  These use a common utility macro that
- * returns a mask for a given pass - the offset 'off' selects the row or
- * column version.  The mask has the appropriate bit set for each column in
- * the tile.
- */
-#define PNG_PASS_MASK(pass,off) ( \
-   ((0x110145AF>>(((7-(off))-(pass))<<2)) & 0xF) | \
-   ((0x01145AF0>>(((7-(off))-(pass))<<2)) & 0xF0))
-
-#define PNG_ROW_IN_INTERLACE_PASS(y, pass) \
-   ((PNG_PASS_MASK(pass,0) >> ((y)&7)) & 1)
-#define PNG_COL_IN_INTERLACE_PASS(x, pass) \
-   ((PNG_PASS_MASK(pass,1) >> ((x)&7)) & 1)
-
-#ifdef PNG_READ_COMPOSITE_NODIV_SUPPORTED
-/* With these routines we avoid an integer divide, which will be slower on
- * most machines.  However, it does take more operations than the corresponding
- * divide method, so it may be slower on a few RISC systems.  There are two
- * shifts (by 8 or 16 bits) and an addition, versus a single integer divide.
- *
- * Note that the rounding factors are NOT supposed to be the same!  128 and
- * 32768 are correct for the NODIV code; 127 and 32767 are correct for the
- * standard method.
- *
- * [Optimized code by Greg Roelofs and Mark Adler...blame us for bugs. :-) ]
- */
-
- /* fg and bg should be in `gamma 1.0' space; alpha is the opacity */
-
-#  define png_composite(composite, fg, alpha, bg)         \
-     { png_uint_16 temp = (png_uint_16)((png_uint_16)(fg) \
-           * (png_uint_16)(alpha)                         \
-           + (png_uint_16)(bg)*(png_uint_16)(255          \
-           - (png_uint_16)(alpha)) + 128);                \
-       (composite) = (png_byte)((temp + (temp >> 8)) >> 8); }
-
-#  define png_composite_16(composite, fg, alpha, bg)       \
-     { png_uint_32 temp = (png_uint_32)((png_uint_32)(fg)  \
-           * (png_uint_32)(alpha)                          \
-           + (png_uint_32)(bg)*(65535                      \
-           - (png_uint_32)(alpha)) + 32768);               \
-       (composite) = (png_uint_16)((temp + (temp >> 16)) >> 16); }
-
-#else  /* Standard method using integer division */
-
-#  define png_composite(composite, fg, alpha, bg)                          \
-     (composite) = (png_byte)(((png_uint_16)(fg) * (png_uint_16)(alpha) +  \
-     (png_uint_16)(bg) * (png_uint_16)(255 - (png_uint_16)(alpha)) +       \
-     127) / 255)
-
-#  define png_composite_16(composite, fg, alpha, bg)                         \
-     (composite) = (png_uint_16)(((png_uint_32)(fg) * (png_uint_32)(alpha) + \
-     (png_uint_32)(bg)*(png_uint_32)(65535 - (png_uint_32)(alpha)) +         \
-     32767) / 65535)
-#endif /* PNG_READ_COMPOSITE_NODIV_SUPPORTED */
-
-#ifdef PNG_READ_INT_FUNCTIONS_SUPPORTED
-PNG_EXPORT(201, png_uint_32, png_get_uint_32, (png_const_bytep buf));
-PNG_EXPORT(202, png_uint_16, png_get_uint_16, (png_const_bytep buf));
-PNG_EXPORT(203, png_int_32, png_get_int_32, (png_const_bytep buf));
-#endif
-
-PNG_EXPORT(204, png_uint_32, png_get_uint_31, (png_structp png_ptr,
-    png_const_bytep buf));
-/* No png_get_int_16 -- may be added if there's a real need for it. */
-
-/* Place a 32-bit number into a buffer in PNG byte order (big-endian). */
-#ifdef PNG_WRITE_INT_FUNCTIONS_SUPPORTED
-PNG_EXPORT(205, void, png_save_uint_32, (png_bytep buf, png_uint_32 i));
-#endif
-#ifdef PNG_SAVE_INT_32_SUPPORTED
-PNG_EXPORT(206, void, png_save_int_32, (png_bytep buf, png_int_32 i));
-#endif
-
-/* Place a 16-bit number into a buffer in PNG byte order.
- * The parameter is declared unsigned int, not png_uint_16,
- * just to avoid potential problems on pre-ANSI C compilers.
- */
-#ifdef PNG_WRITE_INT_FUNCTIONS_SUPPORTED
-PNG_EXPORT(207, void, png_save_uint_16, (png_bytep buf, unsigned int i));
-/* No png_save_int_16 -- may be added if there's a real need for it. */
-#endif
-
-#ifdef PNG_USE_READ_MACROS
-/* Inline macros to do direct reads of bytes from the input buffer.
- * The png_get_int_32() routine assumes we are using two's complement
- * format for negative values, which is almost certainly true.
- */
-#  define png_get_uint_32(buf) \
-     (((png_uint_32)(*(buf)) << 24) + \
-      ((png_uint_32)(*((buf) + 1)) << 16) + \
-      ((png_uint_32)(*((buf) + 2)) << 8) + \
-      ((png_uint_32)(*((buf) + 3))))
-
-   /* From libpng-1.4.0 until 1.4.4, the png_get_uint_16 macro (but not the
-    * function) incorrectly returned a value of type png_uint_32.
-    */
-#  define png_get_uint_16(buf) \
-     ((png_uint_16) \
-      (((unsigned int)(*(buf)) << 8) + \
-       ((unsigned int)(*((buf) + 1)))))
-
-#  define png_get_int_32(buf) \
-     ((png_int_32)((*(buf) & 0x80) \
-      ? -((png_int_32)((png_get_uint_32(buf) ^ 0xffffffffL) + 1)) \
-      : (png_int_32)png_get_uint_32(buf)))
-#endif
-
-#if defined(PNG_READ_CHECK_FOR_INVALID_INDEX_SUPPORTED) || \
-    defined(PNG_WRITE_CHECK_FOR_INVALID_INDEX_SUPPORTED)
-PNG_EXPORT(234, void, png_set_check_for_invalid_index, (png_structp png_ptr,
-    int allowed));
-#endif
-
-/* Maintainer: Put new public prototypes here ^, in libpng.3, and project
- * defs
- */
-
-/* The last ordinal number (this is the *last* one already used; the next
- * one to use is one more than this.)  Maintainer, remember to add an entry to
- * scripts/symbols.def as well.
- */
-#ifdef PNG_EXPORT_LAST_ORDINAL
-  PNG_EXPORT_LAST_ORDINAL(234);
-#endif
-
-#ifdef __cplusplus
-}
-#endif
-
-#endif /* PNG_VERSION_INFO_ONLY */
-/* Do not put anything past this line */
-#endif /* PNG_H */
diff --git a/plugingui/png/pngconf.h b/plugingui/png/pngconf.h
deleted file mode 100644
index a364928..0000000
--- a/plugingui/png/pngconf.h
+++ /dev/null
@@ -1,598 +0,0 @@
-
-/* pngconf.h - machine configurable file for libpng
- *
- * libpng version 1.5.13 - September 27, 2012
- *
- * Copyright (c) 1998-2012 Glenn Randers-Pehrson
- * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
- * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)
- *
- * This code is released under the libpng license.
- * For conditions of distribution and use, see the disclaimer
- * and license in png.h
- *
- */
-
-/* Any machine specific code is near the front of this file, so if you
- * are configuring libpng for a machine, you may want to read the section
- * starting here down to where it starts to typedef png_color, png_text,
- * and png_info.
- */
-
-#ifndef PNGCONF_H
-#define PNGCONF_H
-
-#ifndef PNG_BUILDING_SYMBOL_TABLE
-/* PNG_NO_LIMITS_H may be used to turn off the use of the standard C
- * definition file for  machine specific limits, this may impact the
- * correctness of the definitions below (see uses of INT_MAX).
- */
-#  ifndef PNG_NO_LIMITS_H
-#    include <limits.h>
-#  endif
-
-/* For the memory copy APIs (i.e. the standard definitions of these),
- * because this file defines png_memcpy and so on the base APIs must
- * be defined here.
- */
-#  ifdef BSD
-#    include <strings.h>
-#  else
-#    include <string.h>
-#  endif
-
-/* For png_FILE_p - this provides the standard definition of a
- * FILE
- */
-#  ifdef PNG_STDIO_SUPPORTED
-#    include <stdio.h>
-#  endif
-#endif
-
-/* This controls optimization of the reading of 16 and 32 bit values
- * from PNG files.  It can be set on a per-app-file basis - it
- * just changes whether a macro is used when the function is called.
- * The library builder sets the default; if read functions are not
- * built into the library the macro implementation is forced on.
- */
-#ifndef PNG_READ_INT_FUNCTIONS_SUPPORTED
-#  define PNG_USE_READ_MACROS
-#endif
-#if !defined(PNG_NO_USE_READ_MACROS) && !defined(PNG_USE_READ_MACROS)
-#  if PNG_DEFAULT_READ_MACROS
-#    define PNG_USE_READ_MACROS
-#  endif
-#endif
-
-/* COMPILER SPECIFIC OPTIONS.
- *
- * These options are provided so that a variety of difficult compilers
- * can be used.  Some are fixed at build time (e.g. PNG_API_RULE
- * below) but still have compiler specific implementations, others
- * may be changed on a per-file basis when compiling against libpng.
- */
-
-/* The PNGARG macro protects us against machines that don't have function
- * prototypes (ie K&R style headers).  If your compiler does not handle
- * function prototypes, define this macro and use the included ansi2knr.
- * I've always been able to use _NO_PROTO as the indicator, but you may
- * need to drag the empty declaration out in front of here, or change the
- * ifdef to suit your own needs.
- */
-#ifndef PNGARG
-
-#  ifdef OF /* zlib prototype munger */
-#    define PNGARG(arglist) OF(arglist)
-#  else
-
-#    ifdef _NO_PROTO
-#      define PNGARG(arglist) ()
-#    else
-#      define PNGARG(arglist) arglist
-#    endif /* _NO_PROTO */
-
-#  endif /* OF */
-
-#endif /* PNGARG */
-
-/* Function calling conventions.
- * =============================
- * Normally it is not necessary to specify to the compiler how to call
- * a function - it just does it - however on x86 systems derived from
- * Microsoft and Borland C compilers ('IBM PC', 'DOS', 'Windows' systems
- * and some others) there are multiple ways to call a function and the
- * default can be changed on the compiler command line.  For this reason
- * libpng specifies the calling convention of every exported function and
- * every function called via a user supplied function pointer.  This is
- * done in this file by defining the following macros:
- *
- * PNGAPI    Calling convention for exported functions.
- * PNGCBAPI  Calling convention for user provided (callback) functions.
- * PNGCAPI   Calling convention used by the ANSI-C library (required
- *           for longjmp callbacks and sometimes used internally to
- *           specify the calling convention for zlib).
- *
- * These macros should never be overridden.  If it is necessary to
- * change calling convention in a private build this can be done
- * by setting PNG_API_RULE (which defaults to 0) to one of the values
- * below to select the correct 'API' variants.
- *
- * PNG_API_RULE=0 Use PNGCAPI - the 'C' calling convention - throughout.
- *                This is correct in every known environment.
- * PNG_API_RULE=1 Use the operating system convention for PNGAPI and
- *                the 'C' calling convention (from PNGCAPI) for
- *                callbacks (PNGCBAPI).  This is no longer required
- *                in any known environment - if it has to be used
- *                please post an explanation of the problem to the
- *                libpng mailing list.
- *
- * These cases only differ if the operating system does not use the C
- * calling convention, at present this just means the above cases
- * (x86 DOS/Windows sytems) and, even then, this does not apply to
- * Cygwin running on those systems.
- *
- * Note that the value must be defined in pnglibconf.h so that what
- * the application uses to call the library matches the conventions
- * set when building the library.
- */
-
-/* Symbol export
- * =============
- * When building a shared library it is almost always necessary to tell
- * the compiler which symbols to export.  The png.h macro 'PNG_EXPORT'
- * is used to mark the symbols.  On some systems these symbols can be
- * extracted at link time and need no special processing by the compiler,
- * on other systems the symbols are flagged by the compiler and just
- * the declaration requires a special tag applied (unfortunately) in a
- * compiler dependent way.  Some systems can do either.
- *
- * A small number of older systems also require a symbol from a DLL to
- * be flagged to the program that calls it.  This is a problem because
- * we do not know in the header file included by application code that
- * the symbol will come from a shared library, as opposed to a statically
- * linked one.  For this reason the application must tell us by setting
- * the magic flag PNG_USE_DLL to turn on the special processing before
- * it includes png.h.
- *
- * Four additional macros are used to make this happen:
- *
- * PNG_IMPEXP The magic (if any) to cause a symbol to be exported from
- *            the build or imported if PNG_USE_DLL is set - compiler
- *            and system specific.
- *
- * PNG_EXPORT_TYPE(type) A macro that pre or appends PNG_IMPEXP to
- *                       'type', compiler specific.
- *
- * PNG_DLL_EXPORT Set to the magic to use during a libpng build to
- *                make a symbol exported from the DLL.  Not used in the
- *                public header files; see pngpriv.h for how it is used
- *                in the libpng build.
- *
- * PNG_DLL_IMPORT Set to the magic to force the libpng symbols to come
- *                from a DLL - used to define PNG_IMPEXP when
- *                PNG_USE_DLL is set.
- */
-
-/* System specific discovery.
- * ==========================
- * This code is used at build time to find PNG_IMPEXP, the API settings
- * and PNG_EXPORT_TYPE(), it may also set a macro to indicate the DLL
- * import processing is possible.  On Windows/x86 systems it also sets
- * compiler-specific macros to the values required to change the calling
- * conventions of the various functions.
- */
-#if ( defined(_Windows) || defined(_WINDOWS) || defined(WIN32) ||\
-      defined(_WIN32) || defined(__WIN32__) || defined(__CYGWIN__) ) &&\
-    ( defined(_X86_) || defined(_X64_) || defined(_M_IX86) ||\
-      defined(_M_X64) || defined(_M_IA64) )
-  /* Windows system (DOS doesn't support DLLs) running on x86/x64.  Includes
-   * builds under Cygwin or MinGW.  Also includes Watcom builds but these need
-   * special treatment because they are not compatible with GCC or Visual C
-   * because of different calling conventions.
-   */
-#  if PNG_API_RULE == 2
-    /* If this line results in an error, either because __watcall is not
-     * understood or because of a redefine just below you cannot use *this*
-     * build of the library with the compiler you are using.  *This* build was
-     * build using Watcom and applications must also be built using Watcom!
-     */
-#    define PNGCAPI __watcall
-#  endif
-
-#  if defined(__GNUC__) || (defined (_MSC_VER) && (_MSC_VER >= 800))
-#    define PNGCAPI __cdecl
-#    if PNG_API_RULE == 1
-#      define PNGAPI __stdcall
-#    endif
-#  else
-    /* An older compiler, or one not detected (erroneously) above,
-     * if necessary override on the command line to get the correct
-     * variants for the compiler.
-     */
-#    ifndef PNGCAPI
-#      define PNGCAPI _cdecl
-#    endif
-#    if PNG_API_RULE == 1 && !defined(PNGAPI)
-#      define PNGAPI _stdcall
-#    endif
-#  endif /* compiler/api */
-  /* NOTE: PNGCBAPI always defaults to PNGCAPI. */
-
-#  if defined(PNGAPI) && !defined(PNG_USER_PRIVATEBUILD)
-   ERROR: PNG_USER_PRIVATEBUILD must be defined if PNGAPI is changed
-#  endif
-
-#  if (defined(_MSC_VER) && _MSC_VER < 800) ||\
-      (defined(__BORLANDC__) && __BORLANDC__ < 0x500)
-    /* older Borland and MSC
-     * compilers used '__export' and required this to be after
-     * the type.
-     */
-#    ifndef PNG_EXPORT_TYPE
-#      define PNG_EXPORT_TYPE(type) type PNG_IMPEXP
-#    endif
-#    define PNG_DLL_EXPORT __export
-#  else /* newer compiler */
-#    define PNG_DLL_EXPORT __declspec(dllexport)
-#    ifndef PNG_DLL_IMPORT
-#      define PNG_DLL_IMPORT __declspec(dllimport)
-#    endif
-#  endif /* compiler */
-
-#else /* !Windows/x86 */
-#  if (defined(__IBMC__) || defined(__IBMCPP__)) && defined(__OS2__)
-#    define PNGAPI _System
-#  else /* !Windows/x86 && !OS/2 */
-    /* Use the defaults, or define PNG*API on the command line (but
-     * this will have to be done for every compile!)
-     */
-#  endif /* other system, !OS/2 */
-#endif /* !Windows/x86 */
-
-/* Now do all the defaulting . */
-#ifndef PNGCAPI
-#  define PNGCAPI
-#endif
-#ifndef PNGCBAPI
-#  define PNGCBAPI PNGCAPI
-#endif
-#ifndef PNGAPI
-#  define PNGAPI PNGCAPI
-#endif
-
-/* PNG_IMPEXP may be set on the compilation system command line or (if not set)
- * then in an internal header file when building the library, otherwise (when
- * using the library) it is set here.
- */
-#ifndef PNG_IMPEXP
-#  if defined(PNG_USE_DLL) && defined(PNG_DLL_IMPORT)
-     /* This forces use of a DLL, disallowing static linking */
-#    define PNG_IMPEXP PNG_DLL_IMPORT
-#  endif
-
-#  ifndef PNG_IMPEXP
-#    define PNG_IMPEXP
-#  endif
-#endif
-
-/* In 1.5.2 the definition of PNG_FUNCTION has been changed to always treat
- * 'attributes' as a storage class - the attributes go at the start of the
- * function definition, and attributes are always appended regardless of the
- * compiler.  This considerably simplifies these macros but may cause problems
- * if any compilers both need function attributes and fail to handle them as
- * a storage class (this is unlikely.)
- */
-#ifndef PNG_FUNCTION
-#  define PNG_FUNCTION(type, name, args, attributes) attributes type name args
-#endif
-
-#ifndef PNG_EXPORT_TYPE
-#  define PNG_EXPORT_TYPE(type) PNG_IMPEXP type
-#endif
-
-   /* The ordinal value is only relevant when preprocessing png.h for symbol
-    * table entries, so we discard it here.  See the .dfn files in the
-    * scripts directory.
-    */
-#ifndef PNG_EXPORTA
-
-#  define PNG_EXPORTA(ordinal, type, name, args, attributes)\
-      PNG_FUNCTION(PNG_EXPORT_TYPE(type),(PNGAPI name),PNGARG(args), \
-        extern attributes)
-#endif
-
-/* ANSI-C (C90) does not permit a macro to be invoked with an empty argument,
- * so make something non-empty to satisfy the requirement:
- */
-#define PNG_EMPTY /*empty list*/
-
-#define PNG_EXPORT(ordinal, type, name, args)\
-   PNG_EXPORTA(ordinal, type, name, args, PNG_EMPTY)
-
-/* Use PNG_REMOVED to comment out a removed interface. */
-#ifndef PNG_REMOVED
-#  define PNG_REMOVED(ordinal, type, name, args, attributes)
-#endif
-
-#ifndef PNG_CALLBACK
-#  define PNG_CALLBACK(type, name, args) type (PNGCBAPI name) PNGARG(args)
-#endif
-
-/* Support for compiler specific function attributes.  These are used
- * so that where compiler support is available incorrect use of API
- * functions in png.h will generate compiler warnings.
- *
- * Added at libpng-1.2.41.
- */
-
-#ifndef PNG_NO_PEDANTIC_WARNINGS
-#  ifndef PNG_PEDANTIC_WARNINGS_SUPPORTED
-#    define PNG_PEDANTIC_WARNINGS_SUPPORTED
-#  endif
-#endif
-
-#ifdef PNG_PEDANTIC_WARNINGS_SUPPORTED
-  /* Support for compiler specific function attributes.  These are used
-   * so that where compiler support is available incorrect use of API
-   * functions in png.h will generate compiler warnings.  Added at libpng
-   * version 1.2.41.
-   */
-#  if defined(__GNUC__)
-#    ifndef PNG_USE_RESULT
-#      define PNG_USE_RESULT __attribute__((__warn_unused_result__))
-#    endif
-#    ifndef PNG_NORETURN
-#      define PNG_NORETURN   __attribute__((__noreturn__))
-#    endif
-#    if __GNUC__ >= 3
-#      ifndef PNG_ALLOCATED
-#        define PNG_ALLOCATED  __attribute__((__malloc__))
-#      endif
-#      ifndef PNG_DEPRECATED
-#        define PNG_DEPRECATED __attribute__((__deprecated__))
-#      endif
-#      ifndef PNG_PRIVATE
-#        if 0 /* Doesn't work so we use deprecated instead*/
-#          define PNG_PRIVATE \
-            __attribute__((warning("This function is not exported by libpng.")))
-#        else
-#          define PNG_PRIVATE \
-            __attribute__((__deprecated__))
-#        endif
-#      endif
-#    endif /*  __GNUC__ >= 3 */
-#  endif /* __GNUC__ */
-
-#  if defined(_MSC_VER)  && (_MSC_VER >= 1300)
-#    ifndef PNG_USE_RESULT
-#      define PNG_USE_RESULT /* not supported */
-#    endif
-#    ifndef PNG_NORETURN
-#      define PNG_NORETURN __declspec(noreturn)
-#    endif
-#    ifndef PNG_ALLOCATED
-#      if (_MSC_VER >= 1400)
-#        define PNG_ALLOCATED __declspec(restrict)
-#      endif
-#    endif
-#    ifndef PNG_DEPRECATED
-#      define PNG_DEPRECATED __declspec(deprecated)
-#    endif
-#    ifndef PNG_PRIVATE
-#      define PNG_PRIVATE __declspec(deprecated)
-#    endif
-#  endif /* _MSC_VER */
-#endif /* PNG_PEDANTIC_WARNINGS */
-
-#ifndef PNG_DEPRECATED
-#  define PNG_DEPRECATED  /* Use of this function is deprecated */
-#endif
-#ifndef PNG_USE_RESULT
-#  define PNG_USE_RESULT  /* The result of this function must be checked */
-#endif
-#ifndef PNG_NORETURN
-#  define PNG_NORETURN    /* This function does not return */
-#endif
-#ifndef PNG_ALLOCATED
-#  define PNG_ALLOCATED   /* The result of the function is new memory */
-#endif
-#ifndef PNG_PRIVATE
-#  define PNG_PRIVATE     /* This is a private libpng function */
-#endif
-#ifndef PNG_FP_EXPORT     /* A floating point API. */
-#  ifdef PNG_FLOATING_POINT_SUPPORTED
-#     define PNG_FP_EXPORT(ordinal, type, name, args)\
-         PNG_EXPORT(ordinal, type, name, args);
-#  else                   /* No floating point APIs */
-#     define PNG_FP_EXPORT(ordinal, type, name, args)
-#  endif
-#endif
-#ifndef PNG_FIXED_EXPORT  /* A fixed point API. */
-#  ifdef PNG_FIXED_POINT_SUPPORTED
-#     define PNG_FIXED_EXPORT(ordinal, type, name, args)\
-         PNG_EXPORT(ordinal, type, name, args);
-#  else                   /* No fixed point APIs */
-#     define PNG_FIXED_EXPORT(ordinal, type, name, args)
-#  endif
-#endif
-
-/* The following uses const char * instead of char * for error
- * and warning message functions, so some compilers won't complain.
- * If you do not want to use const, define PNG_NO_CONST here.
- *
- * This should not change how the APIs are called, so it can be done
- * on a per-file basis in the application.
- */
-#ifndef PNG_CONST
-#  ifndef PNG_NO_CONST
-#    define PNG_CONST const
-#  else
-#    define PNG_CONST
-#  endif
-#endif
-
-/* Some typedefs to get us started.  These should be safe on most of the
- * common platforms.  The typedefs should be at least as large as the
- * numbers suggest (a png_uint_32 must be at least 32 bits long), but they
- * don't have to be exactly that size.  Some compilers dislike passing
- * unsigned shorts as function parameters, so you may be better off using
- * unsigned int for png_uint_16.
- */
-
-#if defined(INT_MAX) && (INT_MAX > 0x7ffffffeL)
-typedef unsigned int png_uint_32;
-typedef int png_int_32;
-#else
-typedef unsigned long png_uint_32;
-typedef long png_int_32;
-#endif
-typedef unsigned short png_uint_16;
-typedef short png_int_16;
-typedef unsigned char png_byte;
-
-#ifdef PNG_NO_SIZE_T
-typedef unsigned int png_size_t;
-#else
-typedef size_t png_size_t;
-#endif
-#define png_sizeof(x) (sizeof (x))
-
-/* The following is needed for medium model support.  It cannot be in the
- * pngpriv.h header.  Needs modification for other compilers besides
- * MSC.  Model independent support declares all arrays and pointers to be
- * large using the far keyword.  The zlib version used must also support
- * model independent data.  As of version zlib 1.0.4, the necessary changes
- * have been made in zlib.  The USE_FAR_KEYWORD define triggers other
- * changes that are needed. (Tim Wegner)
- */
-
-/* Separate compiler dependencies (problem here is that zlib.h always
- * defines FAR. (SJT)
- */
-#ifdef __BORLANDC__
-#  if defined(__LARGE__) || defined(__HUGE__) || defined(__COMPACT__)
-#    define LDATA 1
-#  else
-#    define LDATA 0
-#  endif
-  /* GRR:  why is Cygwin in here?  Cygwin is not Borland C... */
-#  if !defined(__WIN32__) && !defined(__FLAT__) && !defined(__CYGWIN__)
-#    define PNG_MAX_MALLOC_64K /* only used in build */
-#    if (LDATA != 1)
-#      ifndef FAR
-#        define FAR __far
-#      endif
-#      define USE_FAR_KEYWORD
-#    endif   /* LDATA != 1 */
-         /* Possibly useful for moving data out of default segment.
-          * Uncomment it if you want. Could also define FARDATA as
-          * const if your compiler supports it. (SJT)
-#        define FARDATA FAR
-          */
-#  endif  /* __WIN32__, __FLAT__, __CYGWIN__ */
-#endif   /* __BORLANDC__ */
-
-
-/* Suggest testing for specific compiler first before testing for
- * FAR.  The Watcom compiler defines both __MEDIUM__ and M_I86MM,
- * making reliance oncertain keywords suspect. (SJT)
- */
-
-/* MSC Medium model */
-#ifdef FAR
-#  ifdef M_I86MM
-#    define USE_FAR_KEYWORD
-#    define FARDATA FAR
-#    include <dos.h>
-#  endif
-#endif
-
-/* SJT: default case */
-#ifndef FAR
-#  define FAR
-#endif
-
-/* At this point FAR is always defined */
-#ifndef FARDATA
-#  define FARDATA
-#endif
-
-/* Typedef for floating-point numbers that are converted
- * to fixed-point with a multiple of 100,000, e.g., gamma
- */
-typedef png_int_32 png_fixed_point;
-
-/* Add typedefs for pointers */
-typedef void                      FAR * png_voidp;
-typedef PNG_CONST void            FAR * png_const_voidp;
-typedef png_byte                  FAR * png_bytep;
-typedef PNG_CONST png_byte        FAR * png_const_bytep;
-typedef png_uint_32               FAR * png_uint_32p;
-typedef PNG_CONST png_uint_32     FAR * png_const_uint_32p;
-typedef png_int_32                FAR * png_int_32p;
-typedef PNG_CONST png_int_32      FAR * png_const_int_32p;
-typedef png_uint_16               FAR * png_uint_16p;
-typedef PNG_CONST png_uint_16     FAR * png_const_uint_16p;
-typedef png_int_16                FAR * png_int_16p;
-typedef PNG_CONST png_int_16      FAR * png_const_int_16p;
-typedef char                      FAR * png_charp;
-typedef PNG_CONST char            FAR * png_const_charp;
-typedef png_fixed_point           FAR * png_fixed_point_p;
-typedef PNG_CONST png_fixed_point FAR * png_const_fixed_point_p;
-typedef png_size_t                FAR * png_size_tp;
-typedef PNG_CONST png_size_t      FAR * png_const_size_tp;
-
-#ifdef PNG_STDIO_SUPPORTED
-typedef FILE            * png_FILE_p;
-#endif
-
-#ifdef PNG_FLOATING_POINT_SUPPORTED
-typedef double           FAR * png_doublep;
-typedef PNG_CONST double FAR * png_const_doublep;
-#endif
-
-/* Pointers to pointers; i.e. arrays */
-typedef png_byte        FAR * FAR * png_bytepp;
-typedef png_uint_32     FAR * FAR * png_uint_32pp;
-typedef png_int_32      FAR * FAR * png_int_32pp;
-typedef png_uint_16     FAR * FAR * png_uint_16pp;
-typedef png_int_16      FAR * FAR * png_int_16pp;
-typedef PNG_CONST char  FAR * FAR * png_const_charpp;
-typedef char            FAR * FAR * png_charpp;
-typedef png_fixed_point FAR * FAR * png_fixed_point_pp;
-#ifdef PNG_FLOATING_POINT_SUPPORTED
-typedef double          FAR * FAR * png_doublepp;
-#endif
-
-/* Pointers to pointers to pointers; i.e., pointer to array */
-typedef char            FAR * FAR * FAR * png_charppp;
-
-/* png_alloc_size_t is guaranteed to be no smaller than png_size_t,
- * and no smaller than png_uint_32.  Casts from png_size_t or png_uint_32
- * to png_alloc_size_t are not necessary; in fact, it is recommended
- * not to use them at all so that the compiler can complain when something
- * turns out to be problematic.
- * Casts in the other direction (from png_alloc_size_t to png_size_t or
- * png_uint_32) should be explicitly applied; however, we do not expect
- * to encounter practical situations that require such conversions.
- */
-#if defined(__TURBOC__) && !defined(__FLAT__)
-   typedef unsigned long png_alloc_size_t;
-#else
-#  if defined(_MSC_VER) && defined(MAXSEG_64K)
-     typedef unsigned long    png_alloc_size_t;
-#  else
-     /* This is an attempt to detect an old Windows system where (int) is
-      * actually 16 bits, in that case png_malloc must have an argument with a
-      * bigger size to accomodate the requirements of the library.
-      */
-#    if (defined(_Windows) || defined(_WINDOWS) || defined(_WINDOWS_)) && \
-        (!defined(INT_MAX) || INT_MAX <= 0x7ffffffeL)
-       typedef DWORD         png_alloc_size_t;
-#    else
-       typedef png_size_t    png_alloc_size_t;
-#    endif
-#  endif
-#endif
-
-#endif /* PNGCONF_H */
diff --git a/plugingui/png/pngdebug.h b/plugingui/png/pngdebug.h
deleted file mode 100644
index 16f81fd..0000000
--- a/plugingui/png/pngdebug.h
+++ /dev/null
@@ -1,157 +0,0 @@
-
-/* pngdebug.h - Debugging macros for libpng, also used in pngtest.c
- *
- * Copyright (c) 1998-2011 Glenn Randers-Pehrson
- * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
- * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)
- *
- * Last changed in libpng 1.5.0 [January 6, 2011]
- *
- * This code is released under the libpng license.
- * For conditions of distribution and use, see the disclaimer
- * and license in png.h
- */
-
-/* Define PNG_DEBUG at compile time for debugging information.  Higher
- * numbers for PNG_DEBUG mean more debugging information.  This has
- * only been added since version 0.95 so it is not implemented throughout
- * libpng yet, but more support will be added as needed.
- *
- * png_debug[1-2]?(level, message ,arg{0-2})
- *   Expands to a statement (either a simple expression or a compound
- *   do..while(0) statement) that outputs a message with parameter
- *   substitution if PNG_DEBUG is defined to 2 or more.  If PNG_DEBUG
- *   is undefined, 0 or 1 every png_debug expands to a simple expression
- *   (actually ((void)0)).
- *
- *   level: level of detail of message, starting at 0.  A level 'n'
- *          message is preceded by 'n' tab characters (not implemented
- *          on Microsoft compilers unless PNG_DEBUG_FILE is also
- *          defined, to allow debug DLL compilation with no standard IO).
- *   message: a printf(3) style text string.  A trailing '\n' is added
- *            to the message.
- *   arg: 0 to 2 arguments for printf(3) style substitution in message.
- */
-#ifndef PNGDEBUG_H
-#define PNGDEBUG_H
-/* These settings control the formatting of messages in png.c and pngerror.c */
-/* Moved to pngdebug.h at 1.5.0 */
-#  ifndef PNG_LITERAL_SHARP
-#    define PNG_LITERAL_SHARP 0x23
-#  endif
-#  ifndef PNG_LITERAL_LEFT_SQUARE_BRACKET
-#    define PNG_LITERAL_LEFT_SQUARE_BRACKET 0x5b
-#  endif
-#  ifndef PNG_LITERAL_RIGHT_SQUARE_BRACKET
-#    define PNG_LITERAL_RIGHT_SQUARE_BRACKET 0x5d
-#  endif
-#  ifndef PNG_STRING_NEWLINE
-#    define PNG_STRING_NEWLINE "\n"
-#  endif
-
-#ifdef PNG_DEBUG
-#  if (PNG_DEBUG > 0)
-#    if !defined(PNG_DEBUG_FILE) && defined(_MSC_VER)
-#      include <crtdbg.h>
-#      if (PNG_DEBUG > 1)
-#        ifndef _DEBUG
-#          define _DEBUG
-#        endif
-#        ifndef png_debug
-#          define png_debug(l,m)  _RPT0(_CRT_WARN,m PNG_STRING_NEWLINE)
-#        endif
-#        ifndef png_debug1
-#          define png_debug1(l,m,p1)  _RPT1(_CRT_WARN,m PNG_STRING_NEWLINE,p1)
-#        endif
-#        ifndef png_debug2
-#          define png_debug2(l,m,p1,p2) \
-             _RPT2(_CRT_WARN,m PNG_STRING_NEWLINE,p1,p2)
-#        endif
-#      endif
-#    else /* PNG_DEBUG_FILE || !_MSC_VER */
-#      ifndef PNG_STDIO_SUPPORTED
-#        include <stdio.h> /* not included yet */
-#      endif
-#      ifndef PNG_DEBUG_FILE
-#        define PNG_DEBUG_FILE stderr
-#      endif /* PNG_DEBUG_FILE */
-
-#      if (PNG_DEBUG > 1)
-/* Note: ["%s"m PNG_STRING_NEWLINE] probably does not work on
- * non-ISO compilers
- */
-#        ifdef __STDC__
-#          ifndef png_debug
-#            define png_debug(l,m) \
-       do { \
-       int num_tabs=l; \
-       fprintf(PNG_DEBUG_FILE,"%s"m PNG_STRING_NEWLINE,(num_tabs==1 ? "\t" : \
-         (num_tabs==2 ? "\t\t":(num_tabs>2 ? "\t\t\t":"")))); \
-       } while (0)
-#          endif
-#          ifndef png_debug1
-#            define png_debug1(l,m,p1) \
-       do { \
-       int num_tabs=l; \
-       fprintf(PNG_DEBUG_FILE,"%s"m PNG_STRING_NEWLINE,(num_tabs==1 ? "\t" : \
-         (num_tabs==2 ? "\t\t":(num_tabs>2 ? "\t\t\t":""))),p1); \
-       } while (0)
-#          endif
-#          ifndef png_debug2
-#            define png_debug2(l,m,p1,p2) \
-       do { \
-       int num_tabs=l; \
-       fprintf(PNG_DEBUG_FILE,"%s"m PNG_STRING_NEWLINE,(num_tabs==1 ? "\t" : \
-         (num_tabs==2 ? "\t\t":(num_tabs>2 ? "\t\t\t":""))),p1,p2); \
-       } while (0)
-#          endif
-#        else /* __STDC __ */
-#          ifndef png_debug
-#            define png_debug(l,m) \
-       do { \
-       int num_tabs=l; \
-       char format[256]; \
-       snprintf(format,256,"%s%s%s",(num_tabs==1 ? "\t" : \
-         (num_tabs==2 ? "\t\t":(num_tabs>2 ? "\t\t\t":""))), \
-         m,PNG_STRING_NEWLINE); \
-       fprintf(PNG_DEBUG_FILE,format); \
-       } while (0)
-#          endif
-#          ifndef png_debug1
-#            define png_debug1(l,m,p1) \
-       do { \
-       int num_tabs=l; \
-       char format[256]; \
-       snprintf(format,256,"%s%s%s",(num_tabs==1 ? "\t" : \
-         (num_tabs==2 ? "\t\t":(num_tabs>2 ? "\t\t\t":""))), \
-         m,PNG_STRING_NEWLINE); \
-       fprintf(PNG_DEBUG_FILE,format,p1); \
-       } while (0)
-#          endif
-#          ifndef png_debug2
-#            define png_debug2(l,m,p1,p2) \
-       do { \
-       int num_tabs=l; \
-       char format[256]; \
-       snprintf(format,256,"%s%s%s",(num_tabs==1 ? "\t" : \
-         (num_tabs==2 ? "\t\t":(num_tabs>2 ? "\t\t\t":""))), \
-         m,PNG_STRING_NEWLINE); \
-       fprintf(PNG_DEBUG_FILE,format,p1,p2); \
-       } while (0)
-#          endif
-#        endif /* __STDC __ */
-#      endif /* (PNG_DEBUG > 1) */
-
-#    endif /* _MSC_VER */
-#  endif /* (PNG_DEBUG > 0) */
-#endif /* PNG_DEBUG */
-#ifndef png_debug
-#  define png_debug(l, m) ((void)0)
-#endif
-#ifndef png_debug1
-#  define png_debug1(l, m, p1) ((void)0)
-#endif
-#ifndef png_debug2
-#  define png_debug2(l, m, p1, p2) ((void)0)
-#endif
-#endif /* PNGDEBUG_H */
diff --git a/plugingui/png/pngerror.c b/plugingui/png/pngerror.c
deleted file mode 100644
index 1c64a7f..0000000
--- a/plugingui/png/pngerror.c
+++ /dev/null
@@ -1,685 +0,0 @@
-
-/* pngerror.c - stub functions for i/o and memory allocation
- *
- * Last changed in libpng 1.5.8 [February 1, 2011]
- * Copyright (c) 1998-2011 Glenn Randers-Pehrson
- * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
- * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)
- *
- * This code is released under the libpng license.
- * For conditions of distribution and use, see the disclaimer
- * and license in png.h
- *
- * This file provides a location for all error handling.  Users who
- * need special error handling are expected to write replacement functions
- * and use png_set_error_fn() to use those functions.  See the instructions
- * at each function.
- */
-
-#include "pngpriv.h"
-
-#if defined(PNG_READ_SUPPORTED) || defined(PNG_WRITE_SUPPORTED)
-
-static PNG_FUNCTION(void, png_default_error,PNGARG((png_structp png_ptr,
-    png_const_charp error_message)),PNG_NORETURN);
-
-#ifdef PNG_WARNINGS_SUPPORTED
-static void /* PRIVATE */
-png_default_warning PNGARG((png_structp png_ptr,
-   png_const_charp warning_message));
-#endif /* PNG_WARNINGS_SUPPORTED */
-
-/* This function is called whenever there is a fatal error.  This function
- * should not be changed.  If there is a need to handle errors differently,
- * you should supply a replacement error function and use png_set_error_fn()
- * to replace the error function at run-time.
- */
-#ifdef PNG_ERROR_TEXT_SUPPORTED
-PNG_FUNCTION(void,PNGAPI
-dg_png_error,(png_structp png_ptr, png_const_charp error_message),PNG_NORETURN)
-{
-#ifdef PNG_ERROR_NUMBERS_SUPPORTED
-   char msg[16];
-   if (png_ptr != NULL)
-   {
-      if (png_ptr->flags&
-         (PNG_FLAG_STRIP_ERROR_NUMBERS|PNG_FLAG_STRIP_ERROR_TEXT))
-      {
-         if (*error_message == PNG_LITERAL_SHARP)
-         {
-            /* Strip "#nnnn " from beginning of error message. */
-            int offset;
-            for (offset = 1; offset<15; offset++)
-               if (error_message[offset] == ' ')
-                  break;
-
-            if (png_ptr->flags&PNG_FLAG_STRIP_ERROR_TEXT)
-            {
-               int i;
-               for (i = 0; i < offset - 1; i++)
-                  msg[i] = error_message[i + 1];
-               msg[i - 1] = '\0';
-               error_message = msg;
-            }
-
-            else
-               error_message += offset;
-      }
-
-      else
-      {
-         if (png_ptr->flags&PNG_FLAG_STRIP_ERROR_TEXT)
-         {
-            msg[0] = '0';
-            msg[1] = '\0';
-            error_message = msg;
-         }
-       }
-     }
-   }
-#endif
-   if (png_ptr != NULL && png_ptr->error_fn != NULL)
-      (*(png_ptr->error_fn))(png_ptr, error_message);
-
-   /* If the custom handler doesn't exist, or if it returns,
-      use the default handler, which will not return. */
-   png_default_error(png_ptr, error_message);
-}
-#else
-PNG_FUNCTION(void,PNGAPI
-png_err,(png_structp png_ptr),PNG_NORETURN)
-{
-   /* Prior to 1.5.2 the error_fn received a NULL pointer, expressed
-    * erroneously as '\0', instead of the empty string "".  This was
-    * apparently an error, introduced in libpng-1.2.20, and png_default_error
-    * will crash in this case.
-    */
-   if (png_ptr != NULL && png_ptr->error_fn != NULL)
-      (*(png_ptr->error_fn))(png_ptr, "");
-
-   /* If the custom handler doesn't exist, or if it returns,
-      use the default handler, which will not return. */
-   png_default_error(png_ptr, "");
-}
-#endif /* PNG_ERROR_TEXT_SUPPORTED */
-
-/* Utility to safely appends strings to a buffer.  This never errors out so
- * error checking is not required in the caller.
- */
-size_t
-png_safecat(png_charp buffer, size_t bufsize, size_t pos,
-   png_const_charp string)
-{
-   if (buffer != NULL && pos < bufsize)
-   {
-      if (string != NULL)
-         while (*string != '\0' && pos < bufsize-1)
-           buffer[pos++] = *string++;
-
-      buffer[pos] = '\0';
-   }
-
-   return pos;
-}
-
-#if defined(PNG_WARNINGS_SUPPORTED) || defined(PNG_TIME_RFC1123_SUPPORTED)
-/* Utility to dump an unsigned value into a buffer, given a start pointer and
- * and end pointer (which should point just *beyond* the end of the buffer!)
- * Returns the pointer to the start of the formatted string.
- */
-png_charp
-png_format_number(png_const_charp start, png_charp end, int format,
-   png_alloc_size_t number)
-{
-   int count = 0;    /* number of digits output */
-   int mincount = 1; /* minimum number required */
-   int output = 0;   /* digit output (for the fixed point format) */
-
-   *--end = '\0';
-
-   /* This is written so that the loop always runs at least once, even with
-    * number zero.
-    */
-   while (end > start && (number != 0 || count < mincount))
-   {
-
-      static const char digits[] = "0123456789ABCDEF";
-
-      switch (format)
-      {
-         case PNG_NUMBER_FORMAT_fixed:
-            /* Needs five digits (the fraction) */
-            mincount = 5;
-            if (output || number % 10 != 0)
-            {
-               *--end = digits[number % 10];
-               output = 1;
-            }
-            number /= 10;
-            break;
-
-         case PNG_NUMBER_FORMAT_02u:
-            /* Expects at least 2 digits. */
-            mincount = 2;
-            /* fall through */
-
-         case PNG_NUMBER_FORMAT_u:
-            *--end = digits[number % 10];
-            number /= 10;
-            break;
-
-         case PNG_NUMBER_FORMAT_02x:
-            /* This format expects at least two digits */
-            mincount = 2;
-            /* fall through */
-
-         case PNG_NUMBER_FORMAT_x:
-            *--end = digits[number & 0xf];
-            number >>= 4;
-            break;
-
-         default: /* an error */
-            number = 0;
-            break;
-      }
-
-      /* Keep track of the number of digits added */
-      ++count;
-
-      /* Float a fixed number here: */
-      if (format == PNG_NUMBER_FORMAT_fixed) if (count == 5) if (end > start)
-      {
-         /* End of the fraction, but maybe nothing was output?  In that case
-          * drop the decimal point.  If the number is a true zero handle that
-          * here.
-          */
-         if (output)
-            *--end = '.';
-         else if (number == 0) /* and !output */
-            *--end = '0';
-      }
-   }
-
-   return end;
-}
-#endif
-
-#ifdef PNG_WARNINGS_SUPPORTED
-/* This function is called whenever there is a non-fatal error.  This function
- * should not be changed.  If there is a need to handle warnings differently,
- * you should supply a replacement warning function and use
- * png_set_error_fn() to replace the warning function at run-time.
- */
-void PNGAPI
-png_warning(png_structp png_ptr, png_const_charp warning_message)
-{
-   int offset = 0;
-   if (png_ptr != NULL)
-   {
-#ifdef PNG_ERROR_NUMBERS_SUPPORTED
-   if (png_ptr->flags&
-       (PNG_FLAG_STRIP_ERROR_NUMBERS|PNG_FLAG_STRIP_ERROR_TEXT))
-#endif
-      {
-         if (*warning_message == PNG_LITERAL_SHARP)
-         {
-            for (offset = 1; offset < 15; offset++)
-               if (warning_message[offset] == ' ')
-                  break;
-         }
-      }
-   }
-   if (png_ptr != NULL && png_ptr->warning_fn != NULL)
-      (*(png_ptr->warning_fn))(png_ptr, warning_message + offset);
-   else
-      png_default_warning(png_ptr, warning_message + offset);
-}
-
-/* These functions support 'formatted' warning messages with up to
- * PNG_WARNING_PARAMETER_COUNT parameters.  In the format string the parameter
- * is introduced by @<number>, where 'number' starts at 1.  This follows the
- * standard established by X/Open for internationalizable error messages.
- */
-void
-png_warning_parameter(png_warning_parameters p, int number,
-   png_const_charp string)
-{
-   if (number > 0 && number <= PNG_WARNING_PARAMETER_COUNT)
-      (void)png_safecat(p[number-1], (sizeof p[number-1]), 0, string);
-}
-
-void
-png_warning_parameter_unsigned(png_warning_parameters p, int number, int format,
-   png_alloc_size_t value)
-{
-   char buffer[PNG_NUMBER_BUFFER_SIZE];
-   png_warning_parameter(p, number, PNG_FORMAT_NUMBER(buffer, format, value));
-}
-
-void
-png_warning_parameter_signed(png_warning_parameters p, int number, int format,
-   png_int_32 value)
-{
-   png_alloc_size_t u;
-   png_charp str;
-   char buffer[PNG_NUMBER_BUFFER_SIZE];
-
-   /* Avoid overflow by doing the negate in a png_alloc_size_t: */
-   u = (png_alloc_size_t)value;
-   if (value < 0)
-      u = ~u + 1;
-
-   str = PNG_FORMAT_NUMBER(buffer, format, u);
-
-   if (value < 0 && str > buffer)
-      *--str = '-';
-
-   png_warning_parameter(p, number, str);
-}
-
-void
-png_formatted_warning(png_structp png_ptr, png_warning_parameters p,
-   png_const_charp message)
-{
-   /* The internal buffer is just 192 bytes - enough for all our messages,
-    * overflow doesn't happen because this code checks!  If someone figures
-    * out how to send us a message longer than 192 bytes, all that will
-    * happen is that the message will be truncated appropriately.
-    */
-   size_t i = 0; /* Index in the msg[] buffer: */
-   char msg[192];
-
-   /* Each iteration through the following loop writes at most one character
-    * to msg[i++] then returns here to validate that there is still space for
-    * the trailing '\0'.  It may (in the case of a parameter) read more than
-    * one character from message[]; it must check for '\0' and continue to the
-    * test if it finds the end of string.
-    */
-   while (i<(sizeof msg)-1 && *message != '\0')
-   {
-      /* '@' at end of string is now just printed (previously it was skipped);
-       * it is an error in the calling code to terminate the string with @.
-       */
-      if (p != NULL && *message == '@' && message[1] != '\0')
-      {
-         int parameter_char = *++message; /* Consume the '@' */
-         static const char valid_parameters[] = "123456789";
-         int parameter = 0;
-
-         /* Search for the parameter digit, the index in the string is the
-          * parameter to use.
-          */
-         while (valid_parameters[parameter] != parameter_char &&
-            valid_parameters[parameter] != '\0')
-            ++parameter;
-
-         /* If the parameter digit is out of range it will just get printed. */
-         if (parameter < PNG_WARNING_PARAMETER_COUNT)
-         {
-            /* Append this parameter */
-            png_const_charp parm = p[parameter];
-            png_const_charp pend = p[parameter] + (sizeof p[parameter]);
-
-            /* No need to copy the trailing '\0' here, but there is no guarantee
-             * that parm[] has been initialized, so there is no guarantee of a
-             * trailing '\0':
-             */
-            while (i<(sizeof msg)-1 && *parm != '\0' && parm < pend)
-               msg[i++] = *parm++;
-
-            /* Consume the parameter digit too: */
-            ++message;
-            continue;
-         }
-
-         /* else not a parameter and there is a character after the @ sign; just
-          * copy that.  This is known not to be '\0' because of the test above.
-          */
-      }
-
-      /* At this point *message can't be '\0', even in the bad parameter case
-       * above where there is a lone '@' at the end of the message string.
-       */
-      msg[i++] = *message++;
-   }
-
-   /* i is always less than (sizeof msg), so: */
-   msg[i] = '\0';
-
-   /* And this is the formatted message, it may be larger than
-    * PNG_MAX_ERROR_TEXT, but that is only used for 'chunk' errors and these are
-    * not (currently) formatted.
-    */
-   png_warning(png_ptr, msg);
-}
-#endif /* PNG_WARNINGS_SUPPORTED */
-
-#ifdef PNG_BENIGN_ERRORS_SUPPORTED
-void PNGAPI
-png_benign_error(png_structp png_ptr, png_const_charp error_message)
-{
-  if (png_ptr->flags & PNG_FLAG_BENIGN_ERRORS_WARN)
-     png_warning(png_ptr, error_message);
-  else
-     dg_png_error(png_ptr, error_message);
-}
-#endif
-
-/* These utilities are used internally to build an error message that relates
- * to the current chunk.  The chunk name comes from png_ptr->chunk_name,
- * this is used to prefix the message.  The message is limited in length
- * to 63 bytes, the name characters are output as hex digits wrapped in []
- * if the character is invalid.
- */
-#define isnonalpha(c) ((c) < 65 || (c) > 122 || ((c) > 90 && (c) < 97))
-static PNG_CONST char png_digit[16] = {
-   '0', '1', '2', '3', '4', '5', '6', '7', '8', '9',
-   'A', 'B', 'C', 'D', 'E', 'F'
-};
-
-#define PNG_MAX_ERROR_TEXT 64
-#if defined(PNG_WARNINGS_SUPPORTED) || defined(PNG_ERROR_TEXT_SUPPORTED)
-static void /* PRIVATE */
-png_format_buffer(png_structp png_ptr, png_charp buffer, png_const_charp
-    error_message)
-{
-   png_uint_32 chunk_name = png_ptr->chunk_name;
-   int iout = 0, ishift = 24;
-
-   while (ishift >= 0)
-   {
-      int c = (int)(chunk_name >> ishift) & 0xff;
-
-      ishift -= 8;
-      if (isnonalpha(c))
-      {
-         buffer[iout++] = PNG_LITERAL_LEFT_SQUARE_BRACKET;
-         buffer[iout++] = png_digit[(c & 0xf0) >> 4];
-         buffer[iout++] = png_digit[c & 0x0f];
-         buffer[iout++] = PNG_LITERAL_RIGHT_SQUARE_BRACKET;
-      }
-
-      else
-      {
-         buffer[iout++] = (char)c;
-      }
-   }
-
-   if (error_message == NULL)
-      buffer[iout] = '\0';
-
-   else
-   {
-      int iin = 0;
-
-      buffer[iout++] = ':';
-      buffer[iout++] = ' ';
-
-      while (iin < PNG_MAX_ERROR_TEXT-1 && error_message[iin] != '\0')
-         buffer[iout++] = error_message[iin++];
-
-      /* iin < PNG_MAX_ERROR_TEXT, so the following is safe: */
-      buffer[iout] = '\0';
-   }
-}
-#endif /* PNG_WARNINGS_SUPPORTED || PNG_ERROR_TEXT_SUPPORTED */
-
-#if defined(PNG_READ_SUPPORTED) && defined(PNG_ERROR_TEXT_SUPPORTED)
-PNG_FUNCTION(void,PNGAPI
-png_chunk_error,(png_structp png_ptr, png_const_charp error_message),
-   PNG_NORETURN)
-{
-   char msg[18+PNG_MAX_ERROR_TEXT];
-   if (png_ptr == NULL)
-      dg_png_error(png_ptr, error_message);
-
-   else
-   {
-      png_format_buffer(png_ptr, msg, error_message);
-      dg_png_error(png_ptr, msg);
-   }
-}
-#endif /* PNG_READ_SUPPORTED && PNG_ERROR_TEXT_SUPPORTED */
-
-#ifdef PNG_WARNINGS_SUPPORTED
-void PNGAPI
-png_chunk_warning(png_structp png_ptr, png_const_charp warning_message)
-{
-   char msg[18+PNG_MAX_ERROR_TEXT];
-   if (png_ptr == NULL)
-      png_warning(png_ptr, warning_message);
-
-   else
-   {
-      png_format_buffer(png_ptr, msg, warning_message);
-      png_warning(png_ptr, msg);
-   }
-}
-#endif /* PNG_WARNINGS_SUPPORTED */
-
-#ifdef PNG_READ_SUPPORTED
-#ifdef PNG_BENIGN_ERRORS_SUPPORTED
-void PNGAPI
-png_chunk_benign_error(png_structp png_ptr, png_const_charp error_message)
-{
-   if (png_ptr->flags & PNG_FLAG_BENIGN_ERRORS_WARN)
-      png_chunk_warning(png_ptr, error_message);
-
-   else
-      png_chunk_error(png_ptr, error_message);
-}
-#endif
-#endif /* PNG_READ_SUPPORTED */
-
-#ifdef PNG_ERROR_TEXT_SUPPORTED
-#ifdef PNG_FLOATING_POINT_SUPPORTED
-PNG_FUNCTION(void,
-png_fixed_error,(png_structp png_ptr, png_const_charp name),PNG_NORETURN)
-{
-#  define fixed_message "fixed point overflow in "
-#  define fixed_message_ln ((sizeof fixed_message)-1)
-   int  iin;
-   char msg[fixed_message_ln+PNG_MAX_ERROR_TEXT];
-   png_memcpy(msg, fixed_message, fixed_message_ln);
-   iin = 0;
-   if (name != NULL) while (iin < (PNG_MAX_ERROR_TEXT-1) && name[iin] != 0)
-   {
-      msg[fixed_message_ln + iin] = name[iin];
-      ++iin;
-   }
-   msg[fixed_message_ln + iin] = 0;
-   dg_png_error(png_ptr, msg);
-}
-#endif
-#endif
-
-#ifdef PNG_SETJMP_SUPPORTED
-/* This API only exists if ANSI-C style error handling is used,
- * otherwise it is necessary for png_default_error to be overridden.
- */
-jmp_buf* PNGAPI
-dg_png_set_longjmp_fn(png_structp png_ptr, png_longjmp_ptr longjmp_fn,
-    size_t jmp_buf_size)
-{
-   if (png_ptr == NULL || jmp_buf_size != png_sizeof(jmp_buf))
-      return NULL;
-
-   png_ptr->longjmp_fn = longjmp_fn;
-   return &png_ptr->longjmp_buffer;
-}
-#endif
-
-/* This is the default error handling function.  Note that replacements for
- * this function MUST NOT RETURN, or the program will likely crash.  This
- * function is used by default, or if the program supplies NULL for the
- * error function pointer in png_set_error_fn().
- */
-static PNG_FUNCTION(void /* PRIVATE */,
-png_default_error,(png_structp png_ptr, png_const_charp error_message),
-   PNG_NORETURN)
-{
-#ifdef PNG_CONSOLE_IO_SUPPORTED
-#ifdef PNG_ERROR_NUMBERS_SUPPORTED
-   /* Check on NULL only added in 1.5.4 */
-   if (error_message != NULL && *error_message == PNG_LITERAL_SHARP)
-   {
-      /* Strip "#nnnn " from beginning of error message. */
-      int offset;
-      char error_number[16];
-      for (offset = 0; offset<15; offset++)
-      {
-         error_number[offset] = error_message[offset + 1];
-         if (error_message[offset] == ' ')
-            break;
-      }
-
-      if ((offset > 1) && (offset < 15))
-      {
-         error_number[offset - 1] = '\0';
-         fprintf(stderr, "libpng error no. %s: %s",
-             error_number, error_message + offset + 1);
-         fprintf(stderr, PNG_STRING_NEWLINE);
-      }
-
-      else
-      {
-         fprintf(stderr, "libpng error: %s, offset=%d",
-             error_message, offset);
-         fprintf(stderr, PNG_STRING_NEWLINE);
-      }
-   }
-   else
-#endif
-   {
-      fprintf(stderr, "libpng error: %s", error_message ? error_message :
-         "undefined");
-      fprintf(stderr, PNG_STRING_NEWLINE);
-   }
-#else
-   PNG_UNUSED(error_message) /* Make compiler happy */
-#endif
-   png_longjmp(png_ptr, 1);
-}
-
-PNG_FUNCTION(void,PNGAPI
-png_longjmp,(png_structp png_ptr, int val),PNG_NORETURN)
-{
-#ifdef PNG_SETJMP_SUPPORTED
-   if (png_ptr && png_ptr->longjmp_fn)
-   {
-#  ifdef USE_FAR_KEYWORD
-      {
-         jmp_buf tmp_jmpbuf;
-         png_memcpy(tmp_jmpbuf, png_ptr->longjmp_buffer, png_sizeof(jmp_buf));
-         png_ptr->longjmp_fn(tmp_jmpbuf, val);
-      }
-
-#  else
-   png_ptr->longjmp_fn(png_ptr->longjmp_buffer, val);
-#  endif
-   }
-#endif
-   /* Here if not setjmp support or if png_ptr is null. */
-   PNG_ABORT();
-}
-
-#ifdef PNG_WARNINGS_SUPPORTED
-/* This function is called when there is a warning, but the library thinks
- * it can continue anyway.  Replacement functions don't have to do anything
- * here if you don't want them to.  In the default configuration, png_ptr is
- * not used, but it is passed in case it may be useful.
- */
-static void /* PRIVATE */
-png_default_warning(png_structp png_ptr, png_const_charp warning_message)
-{
-#ifdef PNG_CONSOLE_IO_SUPPORTED
-#  ifdef PNG_ERROR_NUMBERS_SUPPORTED
-   if (*warning_message == PNG_LITERAL_SHARP)
-   {
-      int offset;
-      char warning_number[16];
-      for (offset = 0; offset < 15; offset++)
-      {
-         warning_number[offset] = warning_message[offset + 1];
-         if (warning_message[offset] == ' ')
-            break;
-      }
-
-      if ((offset > 1) && (offset < 15))
-      {
-         warning_number[offset + 1] = '\0';
-         fprintf(stderr, "libpng warning no. %s: %s",
-             warning_number, warning_message + offset);
-         fprintf(stderr, PNG_STRING_NEWLINE);
-      }
-
-      else
-      {
-         fprintf(stderr, "libpng warning: %s",
-             warning_message);
-         fprintf(stderr, PNG_STRING_NEWLINE);
-      }
-   }
-   else
-#  endif
-
-   {
-      fprintf(stderr, "libpng warning: %s", warning_message);
-      fprintf(stderr, PNG_STRING_NEWLINE);
-   }
-#else
-   PNG_UNUSED(warning_message) /* Make compiler happy */
-#endif
-   PNG_UNUSED(png_ptr) /* Make compiler happy */
-}
-#endif /* PNG_WARNINGS_SUPPORTED */
-
-/* This function is called when the application wants to use another method
- * of handling errors and warnings.  Note that the error function MUST NOT
- * return to the calling routine or serious problems will occur.  The return
- * method used in the default routine calls longjmp(png_ptr->longjmp_buffer, 1)
- */
-void PNGAPI
-png_set_error_fn(png_structp png_ptr, png_voidp error_ptr,
-    png_error_ptr error_fn, png_error_ptr warning_fn)
-{
-   if (png_ptr == NULL)
-      return;
-
-   png_ptr->error_ptr = error_ptr;
-   png_ptr->error_fn = error_fn;
-#ifdef PNG_WARNINGS_SUPPORTED
-   png_ptr->warning_fn = warning_fn;
-#else
-   PNG_UNUSED(warning_fn)
-#endif
-}
-
-
-/* This function returns a pointer to the error_ptr associated with the user
- * functions.  The application should free any memory associated with this
- * pointer before png_write_destroy and png_read_destroy are called.
- */
-png_voidp PNGAPI
-png_get_error_ptr(png_const_structp png_ptr)
-{
-   if (png_ptr == NULL)
-      return NULL;
-
-   return ((png_voidp)png_ptr->error_ptr);
-}
-
-
-#ifdef PNG_ERROR_NUMBERS_SUPPORTED
-void PNGAPI
-png_set_strip_error_numbers(png_structp png_ptr, png_uint_32 strip_mode)
-{
-   if (png_ptr != NULL)
-   {
-      png_ptr->flags &=
-         ((~(PNG_FLAG_STRIP_ERROR_NUMBERS |
-         PNG_FLAG_STRIP_ERROR_TEXT))&strip_mode);
-   }
-}
-#endif
-#endif /* PNG_READ_SUPPORTED || PNG_WRITE_SUPPORTED */
diff --git a/plugingui/png/pngget.c b/plugingui/png/pngget.c
deleted file mode 100644
index 65d8487..0000000
--- a/plugingui/png/pngget.c
+++ /dev/null
@@ -1,1124 +0,0 @@
-
-/* pngget.c - retrieval of values from info struct
- *
- * Last changed in libpng 1.5.7 [December 15, 2011]
- * Copyright (c) 1998-2011 Glenn Randers-Pehrson
- * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
- * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)
- *
- * This code is released under the libpng license.
- * For conditions of distribution and use, see the disclaimer
- * and license in png.h
- *
- */
-
-#include "pngpriv.h"
-
-#if defined(PNG_READ_SUPPORTED) || defined(PNG_WRITE_SUPPORTED)
-
-png_uint_32 PNGAPI
-png_get_valid(png_const_structp png_ptr, png_const_infop info_ptr,
-    png_uint_32 flag)
-{
-   if (png_ptr != NULL && info_ptr != NULL)
-      return(info_ptr->valid & flag);
-
-   return(0);
-}
-
-png_size_t PNGAPI
-dg_png_get_rowbytes(png_const_structp png_ptr, png_const_infop info_ptr)
-{
-   if (png_ptr != NULL && info_ptr != NULL)
-      return(info_ptr->rowbytes);
-
-   return(0);
-}
-
-#ifdef PNG_INFO_IMAGE_SUPPORTED
-png_bytepp PNGAPI
-png_get_rows(png_const_structp png_ptr, png_const_infop info_ptr)
-{
-   if (png_ptr != NULL && info_ptr != NULL)
-      return(info_ptr->row_pointers);
-
-   return(0);
-}
-#endif
-
-#ifdef PNG_EASY_ACCESS_SUPPORTED
-/* Easy access to info, added in libpng-0.99 */
-png_uint_32 PNGAPI
-dg_png_get_image_width(png_const_structp png_ptr, png_const_infop info_ptr)
-{
-   if (png_ptr != NULL && info_ptr != NULL)
-      return info_ptr->width;
-
-   return (0);
-}
-
-png_uint_32 PNGAPI
-dg_png_get_image_height(png_const_structp png_ptr, png_const_infop info_ptr)
-{
-   if (png_ptr != NULL && info_ptr != NULL)
-      return info_ptr->height;
-
-   return (0);
-}
-
-png_byte PNGAPI
-png_get_bit_depth(png_const_structp png_ptr, png_const_infop info_ptr)
-{
-   if (png_ptr != NULL && info_ptr != NULL)
-      return info_ptr->bit_depth;
-
-   return (0);
-}
-
-png_byte PNGAPI
-png_get_color_type(png_const_structp png_ptr, png_const_infop info_ptr)
-{
-   if (png_ptr != NULL && info_ptr != NULL)
-      return info_ptr->color_type;
-
-   return (0);
-}
-
-png_byte PNGAPI
-png_get_filter_type(png_const_structp png_ptr, png_const_infop info_ptr)
-{
-   if (png_ptr != NULL && info_ptr != NULL)
-      return info_ptr->filter_type;
-
-   return (0);
-}
-
-png_byte PNGAPI
-png_get_interlace_type(png_const_structp png_ptr, png_const_infop info_ptr)
-{
-   if (png_ptr != NULL && info_ptr != NULL)
-      return info_ptr->interlace_type;
-
-   return (0);
-}
-
-png_byte PNGAPI
-png_get_compression_type(png_const_structp png_ptr, png_const_infop info_ptr)
-{
-   if (png_ptr != NULL && info_ptr != NULL)
-      return info_ptr->compression_type;
-
-   return (0);
-}
-
-png_uint_32 PNGAPI
-png_get_x_pixels_per_meter(png_const_structp png_ptr, png_const_infop info_ptr)
-{
-#ifdef PNG_pHYs_SUPPORTED
-   if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_pHYs))
-      {
-         png_debug1(1, "in %s retrieval function",
-             "png_get_x_pixels_per_meter");
-
-         if (info_ptr->phys_unit_type == PNG_RESOLUTION_METER)
-            return (info_ptr->x_pixels_per_unit);
-      }
-#endif
-
-   return (0);
-}
-
-png_uint_32 PNGAPI
-png_get_y_pixels_per_meter(png_const_structp png_ptr, png_const_infop info_ptr)
-{
-#ifdef PNG_pHYs_SUPPORTED
-   if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_pHYs))
-   {
-      png_debug1(1, "in %s retrieval function",
-          "png_get_y_pixels_per_meter");
-
-      if (info_ptr->phys_unit_type == PNG_RESOLUTION_METER)
-         return (info_ptr->y_pixels_per_unit);
-   }
-#endif
-
-   return (0);
-}
-
-png_uint_32 PNGAPI
-png_get_pixels_per_meter(png_const_structp png_ptr, png_const_infop info_ptr)
-{
-#ifdef PNG_pHYs_SUPPORTED
-   if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_pHYs))
-   {
-      png_debug1(1, "in %s retrieval function", "png_get_pixels_per_meter");
-
-      if (info_ptr->phys_unit_type == PNG_RESOLUTION_METER &&
-          info_ptr->x_pixels_per_unit == info_ptr->y_pixels_per_unit)
-         return (info_ptr->x_pixels_per_unit);
-   }
-#endif
-
-   return (0);
-}
-
-#ifdef PNG_FLOATING_POINT_SUPPORTED
-float PNGAPI
-png_get_pixel_aspect_ratio(png_const_structp png_ptr, png_const_infop info_ptr)
-{
-#ifdef PNG_READ_pHYs_SUPPORTED
-   if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_pHYs))
-   {
-      png_debug1(1, "in %s retrieval function", "png_get_aspect_ratio");
-
-      if (info_ptr->x_pixels_per_unit != 0)
-         return ((float)((float)info_ptr->y_pixels_per_unit
-             /(float)info_ptr->x_pixels_per_unit));
-   }
-#endif
-
-   return ((float)0.0);
-}
-#endif
-
-#ifdef PNG_FIXED_POINT_SUPPORTED
-png_fixed_point PNGAPI
-png_get_pixel_aspect_ratio_fixed(png_const_structp png_ptr,
-    png_const_infop info_ptr)
-{
-#ifdef PNG_READ_pHYs_SUPPORTED
-   if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_pHYs)
-       && info_ptr->x_pixels_per_unit > 0 && info_ptr->y_pixels_per_unit > 0
-       && info_ptr->x_pixels_per_unit <= PNG_UINT_31_MAX
-       && info_ptr->y_pixels_per_unit <= PNG_UINT_31_MAX)
-   {
-      png_fixed_point res;
-
-      png_debug1(1, "in %s retrieval function", "png_get_aspect_ratio_fixed");
-
-      /* The following casts work because a PNG 4 byte integer only has a valid
-       * range of 0..2^31-1; otherwise the cast might overflow.
-       */
-      if (png_muldiv(&res, (png_int_32)info_ptr->y_pixels_per_unit, PNG_FP_1,
-          (png_int_32)info_ptr->x_pixels_per_unit))
-         return res;
-   }
-#endif
-
-   return 0;
-}
-#endif
-
-png_int_32 PNGAPI
-png_get_x_offset_microns(png_const_structp png_ptr, png_const_infop info_ptr)
-{
-#ifdef PNG_oFFs_SUPPORTED
-   if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_oFFs))
-   {
-      png_debug1(1, "in %s retrieval function", "png_get_x_offset_microns");
-
-      if (info_ptr->offset_unit_type == PNG_OFFSET_MICROMETER)
-         return (info_ptr->x_offset);
-   }
-#endif
-
-   return (0);
-}
-
-png_int_32 PNGAPI
-png_get_y_offset_microns(png_const_structp png_ptr, png_const_infop info_ptr)
-{
-#ifdef PNG_oFFs_SUPPORTED
-   if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_oFFs))
-   {
-      png_debug1(1, "in %s retrieval function", "png_get_y_offset_microns");
-
-      if (info_ptr->offset_unit_type == PNG_OFFSET_MICROMETER)
-         return (info_ptr->y_offset);
-   }
-#endif
-
-   return (0);
-}
-
-png_int_32 PNGAPI
-png_get_x_offset_pixels(png_const_structp png_ptr, png_const_infop info_ptr)
-{
-#ifdef PNG_oFFs_SUPPORTED
-   if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_oFFs))
-   {
-      png_debug1(1, "in %s retrieval function", "png_get_x_offset_pixels");
-
-      if (info_ptr->offset_unit_type == PNG_OFFSET_PIXEL)
-         return (info_ptr->x_offset);
-   }
-#endif
-
-   return (0);
-}
-
-png_int_32 PNGAPI
-png_get_y_offset_pixels(png_const_structp png_ptr, png_const_infop info_ptr)
-{
-#ifdef PNG_oFFs_SUPPORTED
-   if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_oFFs))
-   {
-      png_debug1(1, "in %s retrieval function", "png_get_y_offset_pixels");
-
-      if (info_ptr->offset_unit_type == PNG_OFFSET_PIXEL)
-         return (info_ptr->y_offset);
-   }
-#endif
-
-   return (0);
-}
-
-#ifdef PNG_INCH_CONVERSIONS_SUPPORTED
-static png_uint_32
-ppi_from_ppm(png_uint_32 ppm)
-{
-#if 0
-   /* The conversion is *(2.54/100), in binary (32 digits):
-    * .00000110100000001001110101001001
-    */
-   png_uint_32 t1001, t1101;
-   ppm >>= 1;                  /* .1 */
-   t1001 = ppm + (ppm >> 3);   /* .1001 */
-   t1101 = t1001 + (ppm >> 1); /* .1101 */
-   ppm >>= 20;                 /* .000000000000000000001 */
-   t1101 += t1101 >> 15;       /* .1101000000000001101 */
-   t1001 >>= 11;               /* .000000000001001 */
-   t1001 += t1001 >> 12;       /* .000000000001001000000001001 */
-   ppm += t1001;               /* .000000000001001000001001001 */
-   ppm += t1101;               /* .110100000001001110101001001 */
-   return (ppm + 16) >> 5;/* .00000110100000001001110101001001 */
-#else
-   /* The argument is a PNG unsigned integer, so it is not permitted
-    * to be bigger than 2^31.
-    */
-   png_fixed_point result;
-   if (ppm <= PNG_UINT_31_MAX && png_muldiv(&result, (png_int_32)ppm, 127,
-       5000))
-      return result;
-
-   /* Overflow. */
-   return 0;
-#endif
-}
-
-png_uint_32 PNGAPI
-png_get_pixels_per_inch(png_const_structp png_ptr, png_const_infop info_ptr)
-{
-   return ppi_from_ppm(png_get_pixels_per_meter(png_ptr, info_ptr));
-}
-
-png_uint_32 PNGAPI
-png_get_x_pixels_per_inch(png_const_structp png_ptr, png_const_infop info_ptr)
-{
-   return ppi_from_ppm(png_get_x_pixels_per_meter(png_ptr, info_ptr));
-}
-
-png_uint_32 PNGAPI
-png_get_y_pixels_per_inch(png_const_structp png_ptr, png_const_infop info_ptr)
-{
-   return ppi_from_ppm(png_get_y_pixels_per_meter(png_ptr, info_ptr));
-}
-
-#ifdef PNG_FIXED_POINT_SUPPORTED
-static png_fixed_point
-png_fixed_inches_from_microns(png_structp png_ptr, png_int_32 microns)
-{
-   /* Convert from metres * 1,000,000 to inches * 100,000, meters to
-    * inches is simply *(100/2.54), so we want *(10/2.54) == 500/127.
-    * Notice that this can overflow - a warning is output and 0 is
-    * returned.
-    */
-   return png_muldiv_warn(png_ptr, microns, 500, 127);
-}
-
-png_fixed_point PNGAPI
-png_get_x_offset_inches_fixed(png_structp png_ptr,
-    png_const_infop info_ptr)
-{
-   return png_fixed_inches_from_microns(png_ptr,
-       png_get_x_offset_microns(png_ptr, info_ptr));
-}
-#endif
-
-#ifdef PNG_FIXED_POINT_SUPPORTED
-png_fixed_point PNGAPI
-png_get_y_offset_inches_fixed(png_structp png_ptr,
-    png_const_infop info_ptr)
-{
-   return png_fixed_inches_from_microns(png_ptr,
-       png_get_y_offset_microns(png_ptr, info_ptr));
-}
-#endif
-
-#ifdef PNG_FLOATING_POINT_SUPPORTED
-float PNGAPI
-png_get_x_offset_inches(png_const_structp png_ptr, png_const_infop info_ptr)
-{
-   /* To avoid the overflow do the conversion directly in floating
-    * point.
-    */
-   return (float)(png_get_x_offset_microns(png_ptr, info_ptr) * .00003937);
-}
-#endif
-
-#ifdef PNG_FLOATING_POINT_SUPPORTED
-float PNGAPI
-png_get_y_offset_inches(png_const_structp png_ptr, png_const_infop info_ptr)
-{
-   /* To avoid the overflow do the conversion directly in floating
-    * point.
-    */
-   return (float)(png_get_y_offset_microns(png_ptr, info_ptr) * .00003937);
-}
-#endif
-
-#ifdef PNG_pHYs_SUPPORTED
-png_uint_32 PNGAPI
-png_get_pHYs_dpi(png_const_structp png_ptr, png_const_infop info_ptr,
-    png_uint_32 *res_x, png_uint_32 *res_y, int *unit_type)
-{
-   png_uint_32 retval = 0;
-
-   if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_pHYs))
-   {
-      png_debug1(1, "in %s retrieval function", "pHYs");
-
-      if (res_x != NULL)
-      {
-         *res_x = info_ptr->x_pixels_per_unit;
-         retval |= PNG_INFO_pHYs;
-      }
-
-      if (res_y != NULL)
-      {
-         *res_y = info_ptr->y_pixels_per_unit;
-         retval |= PNG_INFO_pHYs;
-      }
-
-      if (unit_type != NULL)
-      {
-         *unit_type = (int)info_ptr->phys_unit_type;
-         retval |= PNG_INFO_pHYs;
-
-         if (*unit_type == 1)
-         {
-            if (res_x != NULL) *res_x = (png_uint_32)(*res_x * .0254 + .50);
-            if (res_y != NULL) *res_y = (png_uint_32)(*res_y * .0254 + .50);
-         }
-      }
-   }
-
-   return (retval);
-}
-#endif /* PNG_pHYs_SUPPORTED */
-#endif  /* PNG_INCH_CONVERSIONS_SUPPORTED */
-
-/* png_get_channels really belongs in here, too, but it's been around longer */
-
-#endif  /* PNG_EASY_ACCESS_SUPPORTED */
-
-png_byte PNGAPI
-png_get_channels(png_const_structp png_ptr, png_const_infop info_ptr)
-{
-   if (png_ptr != NULL && info_ptr != NULL)
-      return(info_ptr->channels);
-
-   return (0);
-}
-
-png_const_bytep PNGAPI
-png_get_signature(png_const_structp png_ptr, png_infop info_ptr)
-{
-   if (png_ptr != NULL && info_ptr != NULL)
-      return(info_ptr->signature);
-
-   return (NULL);
-}
-
-#ifdef PNG_bKGD_SUPPORTED
-png_uint_32 PNGAPI
-png_get_bKGD(png_const_structp png_ptr, png_infop info_ptr,
-   png_color_16p *background)
-{
-   if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_bKGD)
-       && background != NULL)
-   {
-      png_debug1(1, "in %s retrieval function", "bKGD");
-
-      *background = &(info_ptr->background);
-      return (PNG_INFO_bKGD);
-   }
-
-   return (0);
-}
-#endif
-
-#ifdef PNG_cHRM_SUPPORTED
-/* The XYZ APIs were added in 1.5.5 to take advantage of the code added at the
- * same time to correct the rgb grayscale coefficient defaults obtained from the
- * cHRM chunk in 1.5.4
- */
-png_uint_32 PNGFAPI
-png_get_cHRM_XYZ_fixed(png_structp png_ptr, png_const_infop info_ptr,
-    png_fixed_point *int_red_X, png_fixed_point *int_red_Y,
-    png_fixed_point *int_red_Z, png_fixed_point *int_green_X,
-    png_fixed_point *int_green_Y, png_fixed_point *int_green_Z,
-    png_fixed_point *int_blue_X, png_fixed_point *int_blue_Y,
-    png_fixed_point *int_blue_Z)
-{
-   if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_cHRM))
-   {
-      png_xy xy;
-      png_XYZ XYZ;
-
-      png_debug1(1, "in %s retrieval function", "cHRM_XYZ");
-
-      xy.whitex = info_ptr->x_white;
-      xy.whitey = info_ptr->y_white;
-      xy.redx = info_ptr->x_red;
-      xy.redy = info_ptr->y_red;
-      xy.greenx = info_ptr->x_green;
-      xy.greeny = info_ptr->y_green;
-      xy.bluex = info_ptr->x_blue;
-      xy.bluey = info_ptr->y_blue;
-
-      /* The *_checked function handles error reporting, so just return 0 if
-       * there is a failure here.
-       */
-      if (png_XYZ_from_xy_checked(png_ptr, &XYZ, xy))
-      {
-         if (int_red_X != NULL)
-            *int_red_X = XYZ.redX;
-         if (int_red_Y != NULL)
-            *int_red_Y = XYZ.redY;
-         if (int_red_Z != NULL)
-            *int_red_Z = XYZ.redZ;
-         if (int_green_X != NULL)
-            *int_green_X = XYZ.greenX;
-         if (int_green_Y != NULL)
-            *int_green_Y = XYZ.greenY;
-         if (int_green_Z != NULL)
-            *int_green_Z = XYZ.greenZ;
-         if (int_blue_X != NULL)
-            *int_blue_X = XYZ.blueX;
-         if (int_blue_Y != NULL)
-            *int_blue_Y = XYZ.blueY;
-         if (int_blue_Z != NULL)
-            *int_blue_Z = XYZ.blueZ;
-
-         return (PNG_INFO_cHRM);
-      }
-   }
-
-   return (0);
-}
-
-#  ifdef PNG_FLOATING_POINT_SUPPORTED
-png_uint_32 PNGAPI
-png_get_cHRM(png_const_structp png_ptr, png_const_infop info_ptr,
-    double *white_x, double *white_y, double *red_x, double *red_y,
-    double *green_x, double *green_y, double *blue_x, double *blue_y)
-{
-   if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_cHRM))
-   {
-      png_debug1(1, "in %s retrieval function", "cHRM");
-
-      if (white_x != NULL)
-         *white_x = png_float(png_ptr, info_ptr->x_white, "cHRM white X");
-      if (white_y != NULL)
-         *white_y = png_float(png_ptr, info_ptr->y_white, "cHRM white Y");
-      if (red_x != NULL)
-         *red_x = png_float(png_ptr, info_ptr->x_red, "cHRM red X");
-      if (red_y != NULL)
-         *red_y = png_float(png_ptr, info_ptr->y_red, "cHRM red Y");
-      if (green_x != NULL)
-         *green_x = png_float(png_ptr, info_ptr->x_green, "cHRM green X");
-      if (green_y != NULL)
-         *green_y = png_float(png_ptr, info_ptr->y_green, "cHRM green Y");
-      if (blue_x != NULL)
-         *blue_x = png_float(png_ptr, info_ptr->x_blue, "cHRM blue X");
-      if (blue_y != NULL)
-         *blue_y = png_float(png_ptr, info_ptr->y_blue, "cHRM blue Y");
-      return (PNG_INFO_cHRM);
-   }
-
-   return (0);
-}
-
-png_uint_32 PNGAPI
-png_get_cHRM_XYZ(png_structp png_ptr, png_const_infop info_ptr,
-   double *red_X, double *red_Y, double *red_Z, double *green_X,
-   double *green_Y, double *green_Z, double *blue_X, double *blue_Y,
-   double *blue_Z)
-{
-   png_XYZ XYZ;
-
-   if (png_get_cHRM_XYZ_fixed(png_ptr, info_ptr,
-      &XYZ.redX, &XYZ.redY, &XYZ.redZ, &XYZ.greenX, &XYZ.greenY, &XYZ.greenZ,
-      &XYZ.blueX, &XYZ.blueY, &XYZ.blueZ) & PNG_INFO_cHRM)
-   {
-      if (red_X != NULL)
-         *red_X = png_float(png_ptr, XYZ.redX, "cHRM red X");
-      if (red_Y != NULL)
-         *red_Y = png_float(png_ptr, XYZ.redY, "cHRM red Y");
-      if (red_Z != NULL)
-         *red_Z = png_float(png_ptr, XYZ.redZ, "cHRM red Z");
-      if (green_X != NULL)
-         *green_X = png_float(png_ptr, XYZ.greenX, "cHRM green X");
-      if (green_Y != NULL)
-         *green_Y = png_float(png_ptr, XYZ.greenY, "cHRM green Y");
-      if (green_Z != NULL)
-         *green_Z = png_float(png_ptr, XYZ.greenZ, "cHRM green Z");
-      if (blue_X != NULL)
-         *blue_X = png_float(png_ptr, XYZ.blueX, "cHRM blue X");
-      if (blue_Y != NULL)
-         *blue_Y = png_float(png_ptr, XYZ.blueY, "cHRM blue Y");
-      if (blue_Z != NULL)
-         *blue_Z = png_float(png_ptr, XYZ.blueZ, "cHRM blue Z");
-      return (PNG_INFO_cHRM);
-   }
-
-   return (0);
-}
-#  endif
-
-#  ifdef PNG_FIXED_POINT_SUPPORTED
-png_uint_32 PNGAPI
-png_get_cHRM_fixed(png_const_structp png_ptr, png_const_infop info_ptr,
-    png_fixed_point *white_x, png_fixed_point *white_y, png_fixed_point *red_x,
-    png_fixed_point *red_y, png_fixed_point *green_x, png_fixed_point *green_y,
-    png_fixed_point *blue_x, png_fixed_point *blue_y)
-{
-   png_debug1(1, "in %s retrieval function", "cHRM");
-
-   if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_cHRM))
-   {
-      if (white_x != NULL)
-         *white_x = info_ptr->x_white;
-      if (white_y != NULL)
-         *white_y = info_ptr->y_white;
-      if (red_x != NULL)
-         *red_x = info_ptr->x_red;
-      if (red_y != NULL)
-         *red_y = info_ptr->y_red;
-      if (green_x != NULL)
-         *green_x = info_ptr->x_green;
-      if (green_y != NULL)
-         *green_y = info_ptr->y_green;
-      if (blue_x != NULL)
-         *blue_x = info_ptr->x_blue;
-      if (blue_y != NULL)
-         *blue_y = info_ptr->y_blue;
-      return (PNG_INFO_cHRM);
-   }
-
-   return (0);
-}
-#  endif
-#endif
-
-#ifdef PNG_gAMA_SUPPORTED
-png_uint_32 PNGFAPI
-png_get_gAMA_fixed(png_const_structp png_ptr, png_const_infop info_ptr,
-    png_fixed_point *file_gamma)
-{
-   png_debug1(1, "in %s retrieval function", "gAMA");
-
-   if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_gAMA)
-       && file_gamma != NULL)
-   {
-      *file_gamma = info_ptr->gamma;
-      return (PNG_INFO_gAMA);
-   }
-
-   return (0);
-}
-#  ifdef PNG_FLOATING_POINT_SUPPORTED
-png_uint_32 PNGAPI
-png_get_gAMA(png_const_structp png_ptr, png_const_infop info_ptr,
-    double *file_gamma)
-{
-   png_fixed_point igamma;
-   png_uint_32 ok = png_get_gAMA_fixed(png_ptr, info_ptr, &igamma);
-
-   if (ok)
-      *file_gamma = png_float(png_ptr, igamma, "png_get_gAMA");
-
-   return ok;
-}
-
-#  endif
-#endif
-
-#ifdef PNG_sRGB_SUPPORTED
-png_uint_32 PNGAPI
-png_get_sRGB(png_const_structp png_ptr, png_const_infop info_ptr,
-    int *file_srgb_intent)
-{
-   png_debug1(1, "in %s retrieval function", "sRGB");
-
-   if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_sRGB)
-       && file_srgb_intent != NULL)
-   {
-      *file_srgb_intent = (int)info_ptr->srgb_intent;
-      return (PNG_INFO_sRGB);
-   }
-
-   return (0);
-}
-#endif
-
-#ifdef PNG_iCCP_SUPPORTED
-png_uint_32 PNGAPI
-png_get_iCCP(png_const_structp png_ptr, png_const_infop info_ptr,
-    png_charpp name, int *compression_type,
-    png_bytepp profile, png_uint_32 *proflen)
-{
-   png_debug1(1, "in %s retrieval function", "iCCP");
-
-   if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_iCCP)
-       && name != NULL && compression_type != NULL && profile != NULL &&
-		 proflen != NULL)
-   {
-      *name = info_ptr->iccp_name;
-      *profile = info_ptr->iccp_profile;
-      /* Compression_type is a dummy so the API won't have to change
-       * if we introduce multiple compression types later.
-       */
-      *proflen = info_ptr->iccp_proflen;
-      *compression_type = info_ptr->iccp_compression;
-      return (PNG_INFO_iCCP);
-   }
-
-   return (0);
-}
-#endif
-
-#ifdef PNG_sPLT_SUPPORTED
-png_uint_32 PNGAPI
-png_get_sPLT(png_const_structp png_ptr, png_const_infop info_ptr,
-    png_sPLT_tpp spalettes)
-{
-   if (png_ptr != NULL && info_ptr != NULL && spalettes != NULL)
-   {
-      *spalettes = info_ptr->splt_palettes;
-      return ((png_uint_32)info_ptr->splt_palettes_num);
-   }
-
-   return (0);
-}
-#endif
-
-#ifdef PNG_hIST_SUPPORTED
-png_uint_32 PNGAPI
-png_get_hIST(png_const_structp png_ptr, png_const_infop info_ptr,
-    png_uint_16p *hist)
-{
-   png_debug1(1, "in %s retrieval function", "hIST");
-
-   if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_hIST)
-       && hist != NULL)
-   {
-      *hist = info_ptr->hist;
-      return (PNG_INFO_hIST);
-   }
-
-   return (0);
-}
-#endif
-
-png_uint_32 PNGAPI
-png_get_IHDR(png_structp png_ptr, png_infop info_ptr,
-    png_uint_32 *width, png_uint_32 *height, int *bit_depth,
-    int *color_type, int *interlace_type, int *compression_type,
-    int *filter_type)
-
-{
-   png_debug1(1, "in %s retrieval function", "IHDR");
-
-   if (png_ptr == NULL || info_ptr == NULL || width == NULL ||
-       height == NULL || bit_depth == NULL || color_type == NULL)
-      return (0);
-
-   *width = info_ptr->width;
-   *height = info_ptr->height;
-   *bit_depth = info_ptr->bit_depth;
-   *color_type = info_ptr->color_type;
-
-   if (compression_type != NULL)
-      *compression_type = info_ptr->compression_type;
-
-   if (filter_type != NULL)
-      *filter_type = info_ptr->filter_type;
-
-   if (interlace_type != NULL)
-      *interlace_type = info_ptr->interlace_type;
-
-   /* This is redundant if we can be sure that the info_ptr values were all
-    * assigned in png_set_IHDR().  We do the check anyhow in case an
-    * application has ignored our advice not to mess with the members
-    * of info_ptr directly.
-    */
-   png_check_IHDR (png_ptr, info_ptr->width, info_ptr->height,
-       info_ptr->bit_depth, info_ptr->color_type, info_ptr->interlace_type,
-       info_ptr->compression_type, info_ptr->filter_type);
-
-   return (1);
-}
-
-#ifdef PNG_oFFs_SUPPORTED
-png_uint_32 PNGAPI
-png_get_oFFs(png_const_structp png_ptr, png_const_infop info_ptr,
-    png_int_32 *offset_x, png_int_32 *offset_y, int *unit_type)
-{
-   png_debug1(1, "in %s retrieval function", "oFFs");
-
-   if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_oFFs)
-       && offset_x != NULL && offset_y != NULL && unit_type != NULL)
-   {
-      *offset_x = info_ptr->x_offset;
-      *offset_y = info_ptr->y_offset;
-      *unit_type = (int)info_ptr->offset_unit_type;
-      return (PNG_INFO_oFFs);
-   }
-
-   return (0);
-}
-#endif
-
-#ifdef PNG_pCAL_SUPPORTED
-png_uint_32 PNGAPI
-png_get_pCAL(png_const_structp png_ptr, png_const_infop info_ptr,
-    png_charp *purpose, png_int_32 *X0, png_int_32 *X1, int *type, int *nparams,
-    png_charp *units, png_charpp *params)
-{
-   png_debug1(1, "in %s retrieval function", "pCAL");
-
-   if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_pCAL)
-       && purpose != NULL && X0 != NULL && X1 != NULL && type != NULL &&
-       nparams != NULL && units != NULL && params != NULL)
-   {
-      *purpose = info_ptr->pcal_purpose;
-      *X0 = info_ptr->pcal_X0;
-      *X1 = info_ptr->pcal_X1;
-      *type = (int)info_ptr->pcal_type;
-      *nparams = (int)info_ptr->pcal_nparams;
-      *units = info_ptr->pcal_units;
-      *params = info_ptr->pcal_params;
-      return (PNG_INFO_pCAL);
-   }
-
-   return (0);
-}
-#endif
-
-#ifdef PNG_sCAL_SUPPORTED
-#  ifdef PNG_FIXED_POINT_SUPPORTED
-#    ifdef PNG_FLOATING_ARITHMETIC_SUPPORTED
-png_uint_32 PNGAPI
-png_get_sCAL_fixed(png_structp png_ptr, png_const_infop info_ptr,
-    int *unit, png_fixed_point *width, png_fixed_point *height)
-{
-   if (png_ptr != NULL && info_ptr != NULL &&
-       (info_ptr->valid & PNG_INFO_sCAL))
-   {
-      *unit = info_ptr->scal_unit;
-      /*TODO: make this work without FP support */
-      *width = png_fixed(png_ptr, atof(info_ptr->scal_s_width), "sCAL width");
-      *height = png_fixed(png_ptr, atof(info_ptr->scal_s_height),
-         "sCAL height");
-      return (PNG_INFO_sCAL);
-   }
-
-   return(0);
-}
-#    endif /* FLOATING_ARITHMETIC */
-#  endif /* FIXED_POINT */
-#  ifdef PNG_FLOATING_POINT_SUPPORTED
-png_uint_32 PNGAPI
-png_get_sCAL(png_const_structp png_ptr, png_const_infop info_ptr,
-    int *unit, double *width, double *height)
-{
-   if (png_ptr != NULL && info_ptr != NULL &&
-       (info_ptr->valid & PNG_INFO_sCAL))
-   {
-      *unit = info_ptr->scal_unit;
-      *width = atof(info_ptr->scal_s_width);
-      *height = atof(info_ptr->scal_s_height);
-      return (PNG_INFO_sCAL);
-   }
-
-   return(0);
-}
-#  endif /* FLOATING POINT */
-png_uint_32 PNGAPI
-png_get_sCAL_s(png_const_structp png_ptr, png_const_infop info_ptr,
-    int *unit, png_charpp width, png_charpp height)
-{
-   if (png_ptr != NULL && info_ptr != NULL &&
-       (info_ptr->valid & PNG_INFO_sCAL))
-   {
-      *unit = info_ptr->scal_unit;
-      *width = info_ptr->scal_s_width;
-      *height = info_ptr->scal_s_height;
-      return (PNG_INFO_sCAL);
-   }
-
-   return(0);
-}
-#endif /* sCAL */
-
-#ifdef PNG_pHYs_SUPPORTED
-png_uint_32 PNGAPI
-png_get_pHYs(png_const_structp png_ptr, png_const_infop info_ptr,
-    png_uint_32 *res_x, png_uint_32 *res_y, int *unit_type)
-{
-   png_uint_32 retval = 0;
-
-   png_debug1(1, "in %s retrieval function", "pHYs");
-
-   if (png_ptr != NULL && info_ptr != NULL &&
-       (info_ptr->valid & PNG_INFO_pHYs))
-   {
-      if (res_x != NULL)
-      {
-         *res_x = info_ptr->x_pixels_per_unit;
-         retval |= PNG_INFO_pHYs;
-      }
-
-      if (res_y != NULL)
-      {
-         *res_y = info_ptr->y_pixels_per_unit;
-         retval |= PNG_INFO_pHYs;
-      }
-
-      if (unit_type != NULL)
-      {
-         *unit_type = (int)info_ptr->phys_unit_type;
-         retval |= PNG_INFO_pHYs;
-      }
-   }
-
-   return (retval);
-}
-#endif /* pHYs */
-
-png_uint_32 PNGAPI
-png_get_PLTE(png_const_structp png_ptr, png_const_infop info_ptr,
-    png_colorp *palette, int *num_palette)
-{
-   png_debug1(1, "in %s retrieval function", "PLTE");
-
-   if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_PLTE)
-       && palette != NULL)
-   {
-      *palette = info_ptr->palette;
-      *num_palette = info_ptr->num_palette;
-      png_debug1(3, "num_palette = %d", *num_palette);
-      return (PNG_INFO_PLTE);
-   }
-
-   return (0);
-}
-
-#ifdef PNG_sBIT_SUPPORTED
-png_uint_32 PNGAPI
-png_get_sBIT(png_const_structp png_ptr, png_infop info_ptr,
-    png_color_8p *sig_bit)
-{
-   png_debug1(1, "in %s retrieval function", "sBIT");
-
-   if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_sBIT)
-       && sig_bit != NULL)
-   {
-      *sig_bit = &(info_ptr->sig_bit);
-      return (PNG_INFO_sBIT);
-   }
-
-   return (0);
-}
-#endif
-
-#ifdef PNG_TEXT_SUPPORTED
-png_uint_32 PNGAPI
-png_get_text(png_const_structp png_ptr, png_const_infop info_ptr,
-    png_textp *text_ptr, int *num_text)
-{
-   if (png_ptr != NULL && info_ptr != NULL && info_ptr->num_text > 0)
-   {
-      png_debug1(1, "in 0x%lx retrieval function",
-         (unsigned long)png_ptr->chunk_name);
-
-      if (text_ptr != NULL)
-         *text_ptr = info_ptr->text;
-
-      if (num_text != NULL)
-         *num_text = info_ptr->num_text;
-
-      return ((png_uint_32)info_ptr->num_text);
-   }
-
-   if (num_text != NULL)
-      *num_text = 0;
-
-   return(0);
-}
-#endif
-
-#ifdef PNG_tIME_SUPPORTED
-png_uint_32 PNGAPI
-png_get_tIME(png_const_structp png_ptr, png_infop info_ptr, png_timep *mod_time)
-{
-   png_debug1(1, "in %s retrieval function", "tIME");
-
-   if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_tIME)
-       && mod_time != NULL)
-   {
-      *mod_time = &(info_ptr->mod_time);
-      return (PNG_INFO_tIME);
-   }
-
-   return (0);
-}
-#endif
-
-#ifdef PNG_tRNS_SUPPORTED
-png_uint_32 PNGAPI
-png_get_tRNS(png_const_structp png_ptr, png_infop info_ptr,
-    png_bytep *trans_alpha, int *num_trans, png_color_16p *trans_color)
-{
-   png_uint_32 retval = 0;
-   if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_tRNS))
-   {
-      png_debug1(1, "in %s retrieval function", "tRNS");
-
-      if (info_ptr->color_type == PNG_COLOR_TYPE_PALETTE)
-      {
-         if (trans_alpha != NULL)
-         {
-            *trans_alpha = info_ptr->trans_alpha;
-            retval |= PNG_INFO_tRNS;
-         }
-
-         if (trans_color != NULL)
-            *trans_color = &(info_ptr->trans_color);
-      }
-
-      else /* if (info_ptr->color_type != PNG_COLOR_TYPE_PALETTE) */
-      {
-         if (trans_color != NULL)
-         {
-            *trans_color = &(info_ptr->trans_color);
-            retval |= PNG_INFO_tRNS;
-         }
-
-         if (trans_alpha != NULL)
-            *trans_alpha = NULL;
-      }
-
-      if (num_trans != NULL)
-      {
-         *num_trans = info_ptr->num_trans;
-         retval |= PNG_INFO_tRNS;
-      }
-   }
-
-   return (retval);
-}
-#endif
-
-#ifdef PNG_UNKNOWN_CHUNKS_SUPPORTED
-int PNGAPI
-png_get_unknown_chunks(png_const_structp png_ptr, png_const_infop info_ptr,
-    png_unknown_chunkpp unknowns)
-{
-   if (png_ptr != NULL && info_ptr != NULL && unknowns != NULL)
-   {
-      *unknowns = info_ptr->unknown_chunks;
-      return info_ptr->unknown_chunks_num;
-   }
-
-   return (0);
-}
-#endif
-
-#ifdef PNG_READ_RGB_TO_GRAY_SUPPORTED
-png_byte PNGAPI
-png_get_rgb_to_gray_status (png_const_structp png_ptr)
-{
-   return (png_byte)(png_ptr ? png_ptr->rgb_to_gray_status : 0);
-}
-#endif
-
-#ifdef PNG_USER_CHUNKS_SUPPORTED
-png_voidp PNGAPI
-png_get_user_chunk_ptr(png_const_structp png_ptr)
-{
-   return (png_ptr ? png_ptr->user_chunk_ptr : NULL);
-}
-#endif
-
-png_size_t PNGAPI
-png_get_compression_buffer_size(png_const_structp png_ptr)
-{
-   return (png_ptr ? png_ptr->zbuf_size : 0);
-}
-
-#ifdef PNG_SET_USER_LIMITS_SUPPORTED
-/* These functions were added to libpng 1.2.6 and were enabled
- * by default in libpng-1.4.0 */
-png_uint_32 PNGAPI
-png_get_user_width_max (png_const_structp png_ptr)
-{
-   return (png_ptr ? png_ptr->user_width_max : 0);
-}
-
-png_uint_32 PNGAPI
-png_get_user_height_max (png_const_structp png_ptr)
-{
-   return (png_ptr ? png_ptr->user_height_max : 0);
-}
-
-/* This function was added to libpng 1.4.0 */
-png_uint_32 PNGAPI
-png_get_chunk_cache_max (png_const_structp png_ptr)
-{
-   return (png_ptr ? png_ptr->user_chunk_cache_max : 0);
-}
-
-/* This function was added to libpng 1.4.1 */
-png_alloc_size_t PNGAPI
-png_get_chunk_malloc_max (png_const_structp png_ptr)
-{
-   return (png_ptr ? png_ptr->user_chunk_malloc_max : 0);
-}
-#endif /* ?PNG_SET_USER_LIMITS_SUPPORTED */
-
-/* These functions were added to libpng 1.4.0 */
-#ifdef PNG_IO_STATE_SUPPORTED
-png_uint_32 PNGAPI
-png_get_io_state (png_structp png_ptr)
-{
-   return png_ptr->io_state;
-}
-
-png_uint_32 PNGAPI
-png_get_io_chunk_type (png_const_structp png_ptr)
-{
-   return png_ptr->chunk_name;
-}
-
-png_const_bytep PNGAPI
-png_get_io_chunk_name (png_structp png_ptr)
-{
-   PNG_CSTRING_FROM_CHUNK(png_ptr->io_chunk_string, png_ptr->chunk_name);
-   return png_ptr->io_chunk_string;
-}
-#endif /* ?PNG_IO_STATE_SUPPORTED */
-
-#endif /* PNG_READ_SUPPORTED || PNG_WRITE_SUPPORTED */
diff --git a/plugingui/png/pnginfo.h b/plugingui/png/pnginfo.h
deleted file mode 100644
index a33bfab..0000000
--- a/plugingui/png/pnginfo.h
+++ /dev/null
@@ -1,269 +0,0 @@
-
-/* pnginfo.h - header file for PNG reference library
- *
- * Copyright (c) 1998-2011 Glenn Randers-Pehrson
- * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
- * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)
- *
- * Last changed in libpng 1.5.0 [January 6, 2011]
- *
- * This code is released under the libpng license.
- * For conditions of distribution and use, see the disclaimer
- * and license in png.h
- */
-
- /* png_info is a structure that holds the information in a PNG file so
- * that the application can find out the characteristics of the image.
- * If you are reading the file, this structure will tell you what is
- * in the PNG file.  If you are writing the file, fill in the information
- * you want to put into the PNG file, using png_set_*() functions, then
- * call png_write_info().
- *
- * The names chosen should be very close to the PNG specification, so
- * consult that document for information about the meaning of each field.
- *
- * With libpng < 0.95, it was only possible to directly set and read the
- * the values in the png_info_struct, which meant that the contents and
- * order of the values had to remain fixed.  With libpng 0.95 and later,
- * however, there are now functions that abstract the contents of
- * png_info_struct from the application, so this makes it easier to use
- * libpng with dynamic libraries, and even makes it possible to use
- * libraries that don't have all of the libpng ancillary chunk-handing
- * functionality.  In libpng-1.5.0 this was moved into a separate private
- * file that is not visible to applications.
- *
- * The following members may have allocated storage attached that should be
- * cleaned up before the structure is discarded: palette, trans, text,
- * pcal_purpose, pcal_units, pcal_params, hist, iccp_name, iccp_profile,
- * splt_palettes, scal_unit, row_pointers, and unknowns.   By default, these
- * are automatically freed when the info structure is deallocated, if they were
- * allocated internally by libpng.  This behavior can be changed by means
- * of the png_data_freer() function.
- *
- * More allocation details: all the chunk-reading functions that
- * change these members go through the corresponding png_set_*
- * functions.  A function to clear these members is available: see
- * png_free_data().  The png_set_* functions do not depend on being
- * able to point info structure members to any of the storage they are
- * passed (they make their own copies), EXCEPT that the png_set_text
- * functions use the same storage passed to them in the text_ptr or
- * itxt_ptr structure argument, and the png_set_rows and png_set_unknowns
- * functions do not make their own copies.
- */
-#ifndef PNGINFO_H
-#define PNGINFO_H
-
-struct png_info_def
-{
-   /* the following are necessary for every PNG file */
-   png_uint_32 width;  /* width of image in pixels (from IHDR) */
-   png_uint_32 height; /* height of image in pixels (from IHDR) */
-   png_uint_32 valid;  /* valid chunk data (see PNG_INFO_ below) */
-   png_size_t rowbytes; /* bytes needed to hold an untransformed row */
-   png_colorp palette;      /* array of color values (valid & PNG_INFO_PLTE) */
-   png_uint_16 num_palette; /* number of color entries in "palette" (PLTE) */
-   png_uint_16 num_trans;   /* number of transparent palette color (tRNS) */
-   png_byte bit_depth;      /* 1, 2, 4, 8, or 16 bits/channel (from IHDR) */
-   png_byte color_type;     /* see PNG_COLOR_TYPE_ below (from IHDR) */
-   /* The following three should have been named *_method not *_type */
-   png_byte compression_type; /* must be PNG_COMPRESSION_TYPE_BASE (IHDR) */
-   png_byte filter_type;    /* must be PNG_FILTER_TYPE_BASE (from IHDR) */
-   png_byte interlace_type; /* One of PNG_INTERLACE_NONE, PNG_INTERLACE_ADAM7 */
-
-   /* The following is informational only on read, and not used on writes. */
-   png_byte channels;       /* number of data channels per pixel (1, 2, 3, 4) */
-   png_byte pixel_depth;    /* number of bits per pixel */
-   png_byte spare_byte;     /* to align the data, and for future use */
-   png_byte signature[8];   /* magic bytes read by libpng from start of file */
-
-   /* The rest of the data is optional.  If you are reading, check the
-    * valid field to see if the information in these are valid.  If you
-    * are writing, set the valid field to those chunks you want written,
-    * and initialize the appropriate fields below.
-    */
-
-#if defined(PNG_gAMA_SUPPORTED)
-   /* The gAMA chunk describes the gamma characteristics of the system
-    * on which the image was created, normally in the range [1.0, 2.5].
-    * Data is valid if (valid & PNG_INFO_gAMA) is non-zero.
-    */
-   png_fixed_point gamma;
-#endif
-
-#ifdef PNG_sRGB_SUPPORTED
-    /* GR-P, 0.96a */
-    /* Data valid if (valid & PNG_INFO_sRGB) non-zero. */
-   png_byte srgb_intent; /* sRGB rendering intent [0, 1, 2, or 3] */
-#endif
-
-#ifdef PNG_TEXT_SUPPORTED
-   /* The tEXt, and zTXt chunks contain human-readable textual data in
-    * uncompressed, compressed, and optionally compressed forms, respectively.
-    * The data in "text" is an array of pointers to uncompressed,
-    * null-terminated C strings. Each chunk has a keyword that describes the
-    * textual data contained in that chunk.  Keywords are not required to be
-    * unique, and the text string may be empty.  Any number of text chunks may
-    * be in an image.
-    */
-   int num_text; /* number of comments read or comments to write */
-   int max_text; /* current size of text array */
-   png_textp text; /* array of comments read or comments to write */
-#endif /* PNG_TEXT_SUPPORTED */
-
-#ifdef PNG_tIME_SUPPORTED
-   /* The tIME chunk holds the last time the displayed image data was
-    * modified.  See the png_time struct for the contents of this struct.
-    */
-   png_time mod_time;
-#endif
-
-#ifdef PNG_sBIT_SUPPORTED
-   /* The sBIT chunk specifies the number of significant high-order bits
-    * in the pixel data.  Values are in the range [1, bit_depth], and are
-    * only specified for the channels in the pixel data.  The contents of
-    * the low-order bits is not specified.  Data is valid if
-    * (valid & PNG_INFO_sBIT) is non-zero.
-    */
-   png_color_8 sig_bit; /* significant bits in color channels */
-#endif
-
-#if defined(PNG_tRNS_SUPPORTED) || defined(PNG_READ_EXPAND_SUPPORTED) || \
-defined(PNG_READ_BACKGROUND_SUPPORTED)
-   /* The tRNS chunk supplies transparency data for paletted images and
-    * other image types that don't need a full alpha channel.  There are
-    * "num_trans" transparency values for a paletted image, stored in the
-    * same order as the palette colors, starting from index 0.  Values
-    * for the data are in the range [0, 255], ranging from fully transparent
-    * to fully opaque, respectively.  For non-paletted images, there is a
-    * single color specified that should be treated as fully transparent.
-    * Data is valid if (valid & PNG_INFO_tRNS) is non-zero.
-    */
-   png_bytep trans_alpha;    /* alpha values for paletted image */
-   png_color_16 trans_color; /* transparent color for non-palette image */
-#endif
-
-#if defined(PNG_bKGD_SUPPORTED) || defined(PNG_READ_BACKGROUND_SUPPORTED)
-   /* The bKGD chunk gives the suggested image background color if the
-    * display program does not have its own background color and the image
-    * is needs to composited onto a background before display.  The colors
-    * in "background" are normally in the same color space/depth as the
-    * pixel data.  Data is valid if (valid & PNG_INFO_bKGD) is non-zero.
-    */
-   png_color_16 background;
-#endif
-
-#ifdef PNG_oFFs_SUPPORTED
-   /* The oFFs chunk gives the offset in "offset_unit_type" units rightwards
-    * and downwards from the top-left corner of the display, page, or other
-    * application-specific co-ordinate space.  See the PNG_OFFSET_ defines
-    * below for the unit types.  Valid if (valid & PNG_INFO_oFFs) non-zero.
-    */
-   png_int_32 x_offset; /* x offset on page */
-   png_int_32 y_offset; /* y offset on page */
-   png_byte offset_unit_type; /* offset units type */
-#endif
-
-#ifdef PNG_pHYs_SUPPORTED
-   /* The pHYs chunk gives the physical pixel density of the image for
-    * display or printing in "phys_unit_type" units (see PNG_RESOLUTION_
-    * defines below).  Data is valid if (valid & PNG_INFO_pHYs) is non-zero.
-    */
-   png_uint_32 x_pixels_per_unit; /* horizontal pixel density */
-   png_uint_32 y_pixels_per_unit; /* vertical pixel density */
-   png_byte phys_unit_type; /* resolution type (see PNG_RESOLUTION_ below) */
-#endif
-
-#ifdef PNG_hIST_SUPPORTED
-   /* The hIST chunk contains the relative frequency or importance of the
-    * various palette entries, so that a viewer can intelligently select a
-    * reduced-color palette, if required.  Data is an array of "num_palette"
-    * values in the range [0,65535]. Data valid if (valid & PNG_INFO_hIST)
-    * is non-zero.
-    */
-   png_uint_16p hist;
-#endif
-
-#ifdef PNG_cHRM_SUPPORTED
-   /* The cHRM chunk describes the CIE color characteristics of the monitor
-    * on which the PNG was created.  This data allows the viewer to do gamut
-    * mapping of the input image to ensure that the viewer sees the same
-    * colors in the image as the creator.  Values are in the range
-    * [0.0, 0.8].  Data valid if (valid & PNG_INFO_cHRM) non-zero.
-    */
-   png_fixed_point x_white;
-   png_fixed_point y_white;
-   png_fixed_point x_red;
-   png_fixed_point y_red;
-   png_fixed_point x_green;
-   png_fixed_point y_green;
-   png_fixed_point x_blue;
-   png_fixed_point y_blue;
-#endif
-
-#ifdef PNG_pCAL_SUPPORTED
-   /* The pCAL chunk describes a transformation between the stored pixel
-    * values and original physical data values used to create the image.
-    * The integer range [0, 2^bit_depth - 1] maps to the floating-point
-    * range given by [pcal_X0, pcal_X1], and are further transformed by a
-    * (possibly non-linear) transformation function given by "pcal_type"
-    * and "pcal_params" into "pcal_units".  Please see the PNG_EQUATION_
-    * defines below, and the PNG-Group's PNG extensions document for a
-    * complete description of the transformations and how they should be
-    * implemented, and for a description of the ASCII parameter strings.
-    * Data values are valid if (valid & PNG_INFO_pCAL) non-zero.
-    */
-   png_charp pcal_purpose;  /* pCAL chunk description string */
-   png_int_32 pcal_X0;      /* minimum value */
-   png_int_32 pcal_X1;      /* maximum value */
-   png_charp pcal_units;    /* Latin-1 string giving physical units */
-   png_charpp pcal_params;  /* ASCII strings containing parameter values */
-   png_byte pcal_type;      /* equation type (see PNG_EQUATION_ below) */
-   png_byte pcal_nparams;   /* number of parameters given in pcal_params */
-#endif
-
-/* New members added in libpng-1.0.6 */
-   png_uint_32 free_me;     /* flags items libpng is responsible for freeing */
-
-#if defined(PNG_UNKNOWN_CHUNKS_SUPPORTED) || \
- defined(PNG_HANDLE_AS_UNKNOWN_SUPPORTED)
-   /* Storage for unknown chunks that the library doesn't recognize. */
-   png_unknown_chunkp unknown_chunks;
-   int unknown_chunks_num;
-#endif
-
-#ifdef PNG_iCCP_SUPPORTED
-   /* iCCP chunk data. */
-   png_charp iccp_name;     /* profile name */
-   png_bytep iccp_profile;  /* International Color Consortium profile data */
-   png_uint_32 iccp_proflen;  /* ICC profile data length */
-   png_byte iccp_compression; /* Always zero */
-#endif
-
-#ifdef PNG_sPLT_SUPPORTED
-   /* Data on sPLT chunks (there may be more than one). */
-   png_sPLT_tp splt_palettes;
-   png_uint_32 splt_palettes_num;
-#endif
-
-#ifdef PNG_sCAL_SUPPORTED
-   /* The sCAL chunk describes the actual physical dimensions of the
-    * subject matter of the graphic.  The chunk contains a unit specification
-    * a byte value, and two ASCII strings representing floating-point
-    * values.  The values are width and height corresponsing to one pixel
-    * in the image.  Data values are valid if (valid & PNG_INFO_sCAL) is
-    * non-zero.
-    */
-   png_byte scal_unit;         /* unit of physical scale */
-   png_charp scal_s_width;     /* string containing height */
-   png_charp scal_s_height;    /* string containing width */
-#endif
-
-#ifdef PNG_INFO_IMAGE_SUPPORTED
-   /* Memory has been allocated if (valid & PNG_ALLOCATED_INFO_ROWS)
-      non-zero */
-   /* Data valid if (valid & PNG_INFO_IDAT) non-zero */
-   png_bytepp row_pointers;        /* the image bits */
-#endif
-
-};
-#endif /* PNGINFO_H */
diff --git a/plugingui/png/pnglibconf.h b/plugingui/png/pnglibconf.h
deleted file mode 100644
index 92a92ee..0000000
--- a/plugingui/png/pnglibconf.h
+++ /dev/null
@@ -1,186 +0,0 @@
-
-/* libpng STANDARD API DEFINITION */
-
-/* pnglibconf.h - library build configuration */
-
-/* Libpng 1.5.13 - September 27, 2012 */
-
-/* Copyright (c) 1998-2012 Glenn Randers-Pehrson */
-
-/* This code is released under the libpng license. */
-/* For conditions of distribution and use, see the disclaimer */
-/* and license in png.h */
-
-/* pnglibconf.h */
-/* Derived from: scripts/pnglibconf.dfa */
-/* If you edit this file by hand you must obey the rules expressed in */
-/* pnglibconf.dfa with respect to the dependencies between the following */
-/* symbols.  It is much better to generate a new file using */
-/* scripts/libpngconf.mak */
-
-#ifndef PNGLCONF_H
-#define PNGLCONF_H
-/* settings */
-#define PNG_API_RULE 0
-#define PNG_CALLOC_SUPPORTED
-#define PNG_COST_SHIFT 3
-#define PNG_DEFAULT_READ_MACROS 1
-#define PNG_GAMMA_THRESHOLD_FIXED 5000
-#define PNG_MAX_GAMMA_8 11
-#define PNG_QUANTIZE_BLUE_BITS 5
-#define PNG_QUANTIZE_GREEN_BITS 5
-#define PNG_QUANTIZE_RED_BITS 5
-#define PNG_sCAL_PRECISION 5
-#define PNG_WEIGHT_SHIFT 8
-#define PNG_ZBUF_SIZE 8192
-/* end of settings */
-/* options */
-#define PNG_16BIT_SUPPORTED
-#define PNG_ALIGN_MEMORY_SUPPORTED
-#define PNG_BENIGN_ERRORS_SUPPORTED
-#define PNG_bKGD_SUPPORTED
-#define PNG_BUILD_GRAYSCALE_PALETTE_SUPPORTED
-#define PNG_CHECK_cHRM_SUPPORTED
-#define PNG_CHECK_FOR_INVALID_INDEX_SUPPORTED
-#define PNG_cHRM_SUPPORTED
-#define PNG_CONSOLE_IO_SUPPORTED
-#define PNG_CONVERT_tIME_SUPPORTED
-#define PNG_EASY_ACCESS_SUPPORTED
-/*#undef PNG_ERROR_NUMBERS_SUPPORTED*/
-#define PNG_ERROR_TEXT_SUPPORTED
-#define PNG_FIXED_POINT_SUPPORTED
-#define PNG_FLOATING_ARITHMETIC_SUPPORTED
-#define PNG_FLOATING_POINT_SUPPORTED
-#define PNG_gAMA_SUPPORTED
-#define PNG_HANDLE_AS_UNKNOWN_SUPPORTED
-#define PNG_hIST_SUPPORTED
-#define PNG_iCCP_SUPPORTED
-#define PNG_INCH_CONVERSIONS_SUPPORTED
-#define PNG_INFO_IMAGE_SUPPORTED
-#define PNG_IO_STATE_SUPPORTED
-#define PNG_iTXt_SUPPORTED
-#define PNG_MNG_FEATURES_SUPPORTED
-#define PNG_oFFs_SUPPORTED
-#define PNG_pCAL_SUPPORTED
-#define PNG_pHYs_SUPPORTED
-#define PNG_POINTER_INDEXING_SUPPORTED
-#define PNG_PROGRESSIVE_READ_SUPPORTED
-#define PNG_READ_16BIT_SUPPORTED
-#define PNG_READ_ALPHA_MODE_SUPPORTED
-#define PNG_READ_ANCILLARY_CHUNKS_SUPPORTED
-#define PNG_READ_BACKGROUND_SUPPORTED
-#define PNG_READ_BGR_SUPPORTED
-#define PNG_READ_bKGD_SUPPORTED
-#define PNG_READ_CHECK_FOR_INVALID_INDEX_SUPPORTED
-#define PNG_READ_cHRM_SUPPORTED
-#define PNG_READ_COMPOSITE_NODIV_SUPPORTED
-#define PNG_READ_COMPRESSED_TEXT_SUPPORTED
-#define PNG_READ_EXPAND_16_SUPPORTED
-#define PNG_READ_EXPAND_SUPPORTED
-#define PNG_READ_FILLER_SUPPORTED
-#define PNG_READ_gAMA_SUPPORTED
-#define PNG_READ_GAMMA_SUPPORTED
-#define PNG_READ_GRAY_TO_RGB_SUPPORTED
-#define PNG_READ_hIST_SUPPORTED
-#define PNG_READ_iCCP_SUPPORTED
-#define PNG_READ_INTERLACING_SUPPORTED
-#define PNG_READ_INT_FUNCTIONS_SUPPORTED
-#define PNG_READ_INVERT_ALPHA_SUPPORTED
-#define PNG_READ_INVERT_SUPPORTED
-#define PNG_READ_iTXt_SUPPORTED
-#define PNG_READ_oFFs_SUPPORTED
-#define PNG_READ_OPT_PLTE_SUPPORTED
-#define PNG_READ_PACK_SUPPORTED
-#define PNG_READ_PACKSWAP_SUPPORTED
-#define PNG_READ_pCAL_SUPPORTED
-#define PNG_READ_pHYs_SUPPORTED
-#define PNG_READ_QUANTIZE_SUPPORTED
-#define PNG_READ_RGB_TO_GRAY_SUPPORTED
-#define PNG_READ_sBIT_SUPPORTED
-#define PNG_READ_SCALE_16_TO_8_SUPPORTED
-#define PNG_READ_sCAL_SUPPORTED
-#define PNG_READ_SHIFT_SUPPORTED
-#define PNG_READ_sPLT_SUPPORTED
-#define PNG_READ_sRGB_SUPPORTED
-#define PNG_READ_STRIP_16_TO_8_SUPPORTED
-#define PNG_READ_STRIP_ALPHA_SUPPORTED
-#define PNG_READ_SUPPORTED
-#define PNG_READ_SWAP_ALPHA_SUPPORTED
-#define PNG_READ_SWAP_SUPPORTED
-#define PNG_READ_tEXt_SUPPORTED
-#define PNG_READ_TEXT_SUPPORTED
-#define PNG_READ_tIME_SUPPORTED
-#define PNG_READ_TRANSFORMS_SUPPORTED
-#define PNG_READ_tRNS_SUPPORTED
-#define PNG_READ_UNKNOWN_CHUNKS_SUPPORTED
-#define PNG_READ_USER_CHUNKS_SUPPORTED
-#define PNG_READ_USER_TRANSFORM_SUPPORTED
-#define PNG_READ_zTXt_SUPPORTED
-#define PNG_SAVE_INT_32_SUPPORTED
-#define PNG_sBIT_SUPPORTED
-#define PNG_sCAL_SUPPORTED
-#define PNG_SEQUENTIAL_READ_SUPPORTED
-#define PNG_SET_CHUNK_CACHE_LIMIT_SUPPORTED
-#define PNG_SET_CHUNK_MALLOC_LIMIT_SUPPORTED
-#define PNG_SETJMP_SUPPORTED
-#define PNG_SET_USER_LIMITS_SUPPORTED
-#define PNG_sPLT_SUPPORTED
-#define PNG_sRGB_SUPPORTED
-#define PNG_STDIO_SUPPORTED
-#define PNG_tEXt_SUPPORTED
-#define PNG_TEXT_SUPPORTED
-#define PNG_TIME_RFC1123_SUPPORTED
-#define PNG_tIME_SUPPORTED
-#define PNG_tRNS_SUPPORTED
-#define PNG_UNKNOWN_CHUNKS_SUPPORTED
-#define PNG_USER_CHUNKS_SUPPORTED
-#define PNG_USER_LIMITS_SUPPORTED
-#define PNG_USER_MEM_SUPPORTED
-#define PNG_USER_TRANSFORM_INFO_SUPPORTED
-#define PNG_USER_TRANSFORM_PTR_SUPPORTED
-#define PNG_WARNINGS_SUPPORTED
-#define PNG_WRITE_16BIT_SUPPORTED
-#define PNG_WRITE_ANCILLARY_CHUNKS_SUPPORTED
-#define PNG_WRITE_BGR_SUPPORTED
-#define PNG_WRITE_bKGD_SUPPORTED
-#define PNG_WRITE_CHECK_FOR_INVALID_INDEX_SUPPORTED
-#define PNG_WRITE_cHRM_SUPPORTED
-#define PNG_WRITE_COMPRESSED_TEXT_SUPPORTED
-#define PNG_WRITE_CUSTOMIZE_ZTXT_COMPRESSION_SUPPORTED
-#define PNG_WRITE_FILLER_SUPPORTED
-#define PNG_WRITE_FILTER_SUPPORTED
-#define PNG_WRITE_FLUSH_SUPPORTED
-#define PNG_WRITE_gAMA_SUPPORTED
-#define PNG_WRITE_hIST_SUPPORTED
-#define PNG_WRITE_iCCP_SUPPORTED
-#define PNG_WRITE_INTERLACING_SUPPORTED
-#define PNG_WRITE_INT_FUNCTIONS_SUPPORTED
-#define PNG_WRITE_INVERT_ALPHA_SUPPORTED
-#define PNG_WRITE_INVERT_SUPPORTED
-#define PNG_WRITE_iTXt_SUPPORTED
-#define PNG_WRITE_oFFs_SUPPORTED
-#define PNG_WRITE_OPTIMIZE_CMF_SUPPORTED
-#define PNG_WRITE_PACK_SUPPORTED
-#define PNG_WRITE_PACKSWAP_SUPPORTED
-#define PNG_WRITE_pCAL_SUPPORTED
-#define PNG_WRITE_pHYs_SUPPORTED
-#define PNG_WRITE_sBIT_SUPPORTED
-#define PNG_WRITE_sCAL_SUPPORTED
-#define PNG_WRITE_SHIFT_SUPPORTED
-#define PNG_WRITE_sPLT_SUPPORTED
-#define PNG_WRITE_sRGB_SUPPORTED
-#define PNG_WRITE_SUPPORTED
-#define PNG_WRITE_SWAP_ALPHA_SUPPORTED
-#define PNG_WRITE_SWAP_SUPPORTED
-#define PNG_WRITE_tEXt_SUPPORTED
-#define PNG_WRITE_TEXT_SUPPORTED
-#define PNG_WRITE_tIME_SUPPORTED
-#define PNG_WRITE_TRANSFORMS_SUPPORTED
-#define PNG_WRITE_tRNS_SUPPORTED
-#define PNG_WRITE_UNKNOWN_CHUNKS_SUPPORTED
-#define PNG_WRITE_USER_TRANSFORM_SUPPORTED
-#define PNG_WRITE_WEIGHTED_FILTER_SUPPORTED
-#define PNG_WRITE_zTXt_SUPPORTED
-#define PNG_zTXt_SUPPORTED
-/* end of options */
-#endif /* PNGLCONF_H */
diff --git a/plugingui/png/pngmem.c b/plugingui/png/pngmem.c
deleted file mode 100644
index ca258d0..0000000
--- a/plugingui/png/pngmem.c
+++ /dev/null
@@ -1,667 +0,0 @@
-
-/* pngmem.c - stub functions for memory allocation
- *
- * Last changed in libpng 1.5.13 [September 27, 2012]
- * Copyright (c) 1998-2012 Glenn Randers-Pehrson
- * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
- * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)
- *
- * This code is released under the libpng license.
- * For conditions of distribution and use, see the disclaimer
- * and license in png.h
- *
- * This file provides a location for all memory allocation.  Users who
- * need special memory handling are expected to supply replacement
- * functions for png_malloc() and png_free(), and to use
- * png_create_read_struct_2() and png_create_write_struct_2() to
- * identify the replacement functions.
- */
-
-#include "pngpriv.h"
-
-#if defined(PNG_READ_SUPPORTED) || defined(PNG_WRITE_SUPPORTED)
-
-/* Borland DOS special memory handler */
-#if defined(__TURBOC__) && !defined(_Windows) && !defined(__FLAT__)
-/* If you change this, be sure to change the one in png.h also */
-
-/* Allocate memory for a png_struct.  The malloc and memset can be replaced
-   by a single call to calloc() if this is thought to improve performance. */
-PNG_FUNCTION(png_voidp /* PRIVATE */,
-png_create_struct,(int type),PNG_ALLOCATED)
-{
-#  ifdef PNG_USER_MEM_SUPPORTED
-   return (png_create_struct_2(type, NULL, NULL));
-}
-
-/* Alternate version of png_create_struct, for use with user-defined malloc. */
-PNG_FUNCTION(png_voidp /* PRIVATE */,
-png_create_struct_2,(int type, png_malloc_ptr malloc_fn, png_voidp mem_ptr),
-   PNG_ALLOCATED)
-{
-#  endif /* PNG_USER_MEM_SUPPORTED */
-   png_size_t size;
-   png_voidp struct_ptr;
-
-   if (type == PNG_STRUCT_INFO)
-      size = png_sizeof(png_info);
-
-   else if (type == PNG_STRUCT_PNG)
-      size = png_sizeof(png_struct);
-
-   else
-      return (png_get_copyright(NULL));
-
-#  ifdef PNG_USER_MEM_SUPPORTED
-   if (malloc_fn != NULL)
-   {
-      png_struct dummy_struct;
-      png_memset(&dummy_struct, 0, sizeof dummy_struct);
-      dummy_struct.mem_ptr=mem_ptr;
-      struct_ptr = (*(malloc_fn))(&dummy_struct, (png_alloc_size_t)size);
-   }
-
-   else
-#  endif /* PNG_USER_MEM_SUPPORTED */
-   struct_ptr = (png_voidp)farmalloc(size);
-   if (struct_ptr != NULL)
-      png_memset(struct_ptr, 0, size);
-
-   return (struct_ptr);
-}
-
-/* Free memory allocated by a png_create_struct() call */
-void /* PRIVATE */
-png_destroy_struct(png_voidp struct_ptr)
-{
-#  ifdef PNG_USER_MEM_SUPPORTED
-   png_destroy_struct_2(struct_ptr, NULL, NULL);
-}
-
-/* Free memory allocated by a png_create_struct() call */
-void /* PRIVATE */
-png_destroy_struct_2(png_voidp struct_ptr, png_free_ptr free_fn,
-    png_voidp mem_ptr)
-{
-#  endif
-   if (struct_ptr != NULL)
-   {
-#  ifdef PNG_USER_MEM_SUPPORTED
-      if (free_fn != NULL)
-      {
-         png_struct dummy_struct;
-         png_memset(&dummy_struct, 0, sizeof dummy_struct);
-         dummy_struct.mem_ptr=mem_ptr;
-         (*(free_fn))(&dummy_struct, struct_ptr);
-         return;
-      }
-
-#  endif /* PNG_USER_MEM_SUPPORTED */
-      farfree (struct_ptr);
-   }
-}
-
-/* Allocate memory.  For reasonable files, size should never exceed
- * 64K.  However, zlib may allocate more then 64K if you don't tell
- * it not to.  See zconf.h and png.h for more information. zlib does
- * need to allocate exactly 64K, so whatever you call here must
- * have the ability to do that.
- *
- * Borland seems to have a problem in DOS mode for exactly 64K.
- * It gives you a segment with an offset of 8 (perhaps to store its
- * memory stuff).  zlib doesn't like this at all, so we have to
- * detect and deal with it.  This code should not be needed in
- * Windows or OS/2 modes, and only in 16 bit mode.  This code has
- * been updated by Alexander Lehmann for version 0.89 to waste less
- * memory.
- *
- * Note that we can't use png_size_t for the "size" declaration,
- * since on some systems a png_size_t is a 16-bit quantity, and as a
- * result, we would be truncating potentially larger memory requests
- * (which should cause a fatal error) and introducing major problems.
- */
-PNG_FUNCTION(png_voidp,PNGAPI
-png_calloc,(png_structp png_ptr, png_alloc_size_t size),PNG_ALLOCATED)
-{
-   png_voidp ret;
-
-   ret = (png_malloc(png_ptr, size));
-
-   if (ret != NULL)
-      png_memset(ret,0,(png_size_t)size);
-
-   return (ret);
-}
-
-PNG_FUNCTION(png_voidp,PNGAPI
-png_malloc,(png_structp png_ptr, png_alloc_size_t size),PNG_ALLOCATED)
-{
-   png_voidp ret;
-
-   if (png_ptr == NULL || size == 0)
-      return (NULL);
-
-#  ifdef PNG_USER_MEM_SUPPORTED
-   if (png_ptr->malloc_fn != NULL)
-      ret = ((png_voidp)(*(png_ptr->malloc_fn))(png_ptr, size));
-
-   else
-      ret = (png_malloc_default(png_ptr, size));
-
-   if (ret == NULL && (png_ptr->flags&PNG_FLAG_MALLOC_NULL_MEM_OK) == 0)
-       dg_png_error(png_ptr, "Out of memory");
-
-   return (ret);
-}
-
-PNG_FUNCTION(png_voidp,PNGAPI
-png_malloc_default,(png_structp png_ptr, png_alloc_size_t size),PNG_ALLOCATED)
-{
-   png_voidp ret;
-#  endif /* PNG_USER_MEM_SUPPORTED */
-
-   if (png_ptr == NULL || size == 0)
-      return (NULL);
-
-#  ifdef PNG_MAX_MALLOC_64K
-   if (size > (png_uint_32)65536L)
-   {
-      png_warning(png_ptr, "Cannot Allocate > 64K");
-      ret = NULL;
-   }
-
-   else
-#  endif
-
-   if (size != (size_t)size)
-      ret = NULL;
-
-   else if (size == (png_uint_32)65536L)
-   {
-      if (png_ptr->offset_table == NULL)
-      {
-         /* Try to see if we need to do any of this fancy stuff */
-         ret = farmalloc(size);
-         if (ret == NULL || ((png_size_t)ret & 0xffff))
-         {
-            int num_blocks;
-            png_uint_32 total_size;
-            png_bytep table;
-            int i, mem_level, window_bits;
-            png_byte huge * hptr;
-            int window_bits
-
-            if (ret != NULL)
-            {
-               farfree(ret);
-               ret = NULL;
-            }
-
-            window_bits =
-                png_ptr->zlib_window_bits >= png_ptr->zlib_text_window_bits ?
-                png_ptr->zlib_window_bits : png_ptr->zlib_text_window_bits;
-
-            if (window_bits > 14)
-               num_blocks = (int)(1 << (window_bits - 14));
-
-            else
-               num_blocks = 1;
-
-            mem_level =
-                png_ptr->zlib_mem_level >= png_ptr->zlib_text_mem_level ?
-                png_ptr->zlib_mem_level : png_ptr->zlib_text_mem_level;
-
-            if (mem_level >= 7)
-               num_blocks += (int)(1 << (mem_level - 7));
-
-            else
-               num_blocks++;
-
-            total_size = ((png_uint_32)65536L) * (png_uint_32)num_blocks+16;
-
-            table = farmalloc(total_size);
-
-            if (table == NULL)
-            {
-#  ifndef PNG_USER_MEM_SUPPORTED
-               if ((png_ptr->flags&PNG_FLAG_MALLOC_NULL_MEM_OK) == 0)
-                  dg_png_error(png_ptr, "Out Of Memory"); /* Note "O", "M" */
-
-               else
-                  png_warning(png_ptr, "Out Of Memory");
-#  endif
-               return (NULL);
-            }
-
-            if ((png_size_t)table & 0xfff0)
-            {
-#  ifndef PNG_USER_MEM_SUPPORTED
-               if ((png_ptr->flags&PNG_FLAG_MALLOC_NULL_MEM_OK) == 0)
-                  dg_png_error(png_ptr,
-                    "Farmalloc didn't return normalized pointer");
-
-               else
-                  png_warning(png_ptr,
-                    "Farmalloc didn't return normalized pointer");
-#  endif
-               return (NULL);
-            }
-
-            png_ptr->offset_table = table;
-            png_ptr->offset_table_ptr = farmalloc(num_blocks *
-               png_sizeof(png_bytep));
-
-            if (png_ptr->offset_table_ptr == NULL)
-            {
-#  ifndef PNG_USER_MEM_SUPPORTED
-               if ((png_ptr->flags&PNG_FLAG_MALLOC_NULL_MEM_OK) == 0)
-                  dg_png_error(png_ptr, "Out Of memory"); /* Note "O", "m" */
-
-               else
-                  png_warning(png_ptr, "Out Of memory");
-#  endif
-               return (NULL);
-            }
-
-            hptr = (png_byte huge *)table;
-            if ((png_size_t)hptr & 0xf)
-            {
-               hptr = (png_byte huge *)((long)(hptr) & 0xfffffff0L);
-               hptr = hptr + 16L;  /* "hptr += 16L" fails on Turbo C++ 3.0 */
-            }
-
-            for (i = 0; i < num_blocks; i++)
-            {
-               png_ptr->offset_table_ptr[i] = (png_bytep)hptr;
-               hptr = hptr + (png_uint_32)65536L;  /* "+=" fails on TC++3.0 */
-            }
-
-            png_ptr->offset_table_number = num_blocks;
-            png_ptr->offset_table_count = 0;
-            png_ptr->offset_table_count_free = 0;
-         }
-      }
-
-      if (png_ptr->offset_table_count >= png_ptr->offset_table_number)
-      {
-#  ifndef PNG_USER_MEM_SUPPORTED
-         if ((png_ptr->flags&PNG_FLAG_MALLOC_NULL_MEM_OK) == 0)
-            dg_png_error(png_ptr, "Out of Memory"); /* Note "O" and "M" */
-
-         else
-            png_warning(png_ptr, "Out of Memory");
-#  endif
-         return (NULL);
-      }
-
-      ret = png_ptr->offset_table_ptr[png_ptr->offset_table_count++];
-   }
-
-   else
-      ret = farmalloc(size);
-
-#  ifndef PNG_USER_MEM_SUPPORTED
-   if (ret == NULL)
-   {
-      if ((png_ptr->flags&PNG_FLAG_MALLOC_NULL_MEM_OK) == 0)
-         dg_png_error(png_ptr, "Out of memory"); /* Note "o" and "m" */
-
-      else
-         png_warning(png_ptr, "Out of memory"); /* Note "o" and "m" */
-   }
-#  endif
-
-   return (ret);
-}
-
-/* Free a pointer allocated by png_malloc().  In the default
- * configuration, png_ptr is not used, but is passed in case it
- * is needed.  If ptr is NULL, return without taking any action.
- */
-void PNGAPI
-png_free(png_structp png_ptr, png_voidp ptr)
-{
-   if (png_ptr == NULL || ptr == NULL)
-      return;
-
-#  ifdef PNG_USER_MEM_SUPPORTED
-   if (png_ptr->free_fn != NULL)
-   {
-      (*(png_ptr->free_fn))(png_ptr, ptr);
-      return;
-   }
-
-   else
-      png_free_default(png_ptr, ptr);
-}
-
-void PNGAPI
-png_free_default(png_structp png_ptr, png_voidp ptr)
-{
-#  endif /* PNG_USER_MEM_SUPPORTED */
-
-   if (png_ptr == NULL || ptr == NULL)
-      return;
-
-   if (png_ptr->offset_table != NULL)
-   {
-      int i;
-
-      for (i = 0; i < png_ptr->offset_table_count; i++)
-      {
-         if (ptr == png_ptr->offset_table_ptr[i])
-         {
-            ptr = NULL;
-            png_ptr->offset_table_count_free++;
-            break;
-         }
-      }
-      if (png_ptr->offset_table_count_free == png_ptr->offset_table_count)
-      {
-         farfree(png_ptr->offset_table);
-         farfree(png_ptr->offset_table_ptr);
-         png_ptr->offset_table = NULL;
-         png_ptr->offset_table_ptr = NULL;
-      }
-   }
-
-   if (ptr != NULL)
-      farfree(ptr);
-}
-
-#else /* Not the Borland DOS special memory handler */
-
-/* Allocate memory for a png_struct or a png_info.  The malloc and
-   memset can be replaced by a single call to calloc() if this is thought
-   to improve performance noticably. */
-PNG_FUNCTION(png_voidp /* PRIVATE */,
-png_create_struct,(int type),PNG_ALLOCATED)
-{
-#  ifdef PNG_USER_MEM_SUPPORTED
-   return (png_create_struct_2(type, NULL, NULL));
-}
-
-/* Allocate memory for a png_struct or a png_info.  The malloc and
-   memset can be replaced by a single call to calloc() if this is thought
-   to improve performance noticably. */
-PNG_FUNCTION(png_voidp /* PRIVATE */,
-png_create_struct_2,(int type, png_malloc_ptr malloc_fn, png_voidp mem_ptr),
-   PNG_ALLOCATED)
-{
-#  endif /* PNG_USER_MEM_SUPPORTED */
-   png_size_t size;
-   png_voidp struct_ptr;
-
-   if (type == PNG_STRUCT_INFO)
-      size = png_sizeof(png_info);
-
-   else if (type == PNG_STRUCT_PNG)
-      size = png_sizeof(png_struct);
-
-   else
-      return (NULL);
-
-#  ifdef PNG_USER_MEM_SUPPORTED
-   if (malloc_fn != NULL)
-   {
-      png_struct dummy_struct;
-      png_structp png_ptr = &dummy_struct;
-      png_ptr->mem_ptr=mem_ptr;
-      struct_ptr = (*(malloc_fn))(png_ptr, size);
-
-      if (struct_ptr != NULL)
-         png_memset(struct_ptr, 0, size);
-
-      return (struct_ptr);
-   }
-#  endif /* PNG_USER_MEM_SUPPORTED */
-
-#  if defined(__TURBOC__) && !defined(__FLAT__)
-   struct_ptr = (png_voidp)farmalloc(size);
-#  else
-#    if defined(_MSC_VER) && defined(MAXSEG_64K)
-   struct_ptr = (png_voidp)halloc(size, 1);
-#    else
-   struct_ptr = (png_voidp)malloc(size);
-#    endif
-#  endif
-
-   if (struct_ptr != NULL)
-      png_memset(struct_ptr, 0, size);
-
-   return (struct_ptr);
-}
-
-
-/* Free memory allocated by a png_create_struct() call */
-void /* PRIVATE */
-png_destroy_struct(png_voidp struct_ptr)
-{
-#  ifdef PNG_USER_MEM_SUPPORTED
-   png_destroy_struct_2(struct_ptr, NULL, NULL);
-}
-
-/* Free memory allocated by a png_create_struct() call */
-void /* PRIVATE */
-png_destroy_struct_2(png_voidp struct_ptr, png_free_ptr free_fn,
-    png_voidp mem_ptr)
-{
-#  endif /* PNG_USER_MEM_SUPPORTED */
-   if (struct_ptr != NULL)
-   {
-#  ifdef PNG_USER_MEM_SUPPORTED
-      if (free_fn != NULL)
-      {
-         png_struct dummy_struct;
-         png_structp png_ptr = &dummy_struct;
-         png_ptr->mem_ptr=mem_ptr;
-         (*(free_fn))(png_ptr, struct_ptr);
-         return;
-      }
-#  endif /* PNG_USER_MEM_SUPPORTED */
-#  if defined(__TURBOC__) && !defined(__FLAT__)
-      farfree(struct_ptr);
-
-#  else
-#    if defined(_MSC_VER) && defined(MAXSEG_64K)
-      hfree(struct_ptr);
-
-#    else
-      free(struct_ptr);
-
-#    endif
-#  endif
-   }
-}
-
-/* Allocate memory.  For reasonable files, size should never exceed
- * 64K.  However, zlib may allocate more then 64K if you don't tell
- * it not to.  See zconf.h and png.h for more information.  zlib does
- * need to allocate exactly 64K, so whatever you call here must
- * have the ability to do that.
- */
-
-PNG_FUNCTION(png_voidp,PNGAPI
-png_calloc,(png_structp png_ptr, png_alloc_size_t size),PNG_ALLOCATED)
-{
-   png_voidp ret;
-
-   ret = (png_malloc(png_ptr, size));
-
-   if (ret != NULL)
-      png_memset(ret,0,(png_size_t)size);
-
-   return (ret);
-}
-
-PNG_FUNCTION(png_voidp,PNGAPI
-png_malloc,(png_structp png_ptr, png_alloc_size_t size),PNG_ALLOCATED)
-{
-   png_voidp ret;
-
-#  ifdef PNG_USER_MEM_SUPPORTED
-   if (png_ptr == NULL || size == 0)
-      return (NULL);
-
-   if (png_ptr->malloc_fn != NULL)
-      ret = ((png_voidp)(*(png_ptr->malloc_fn))(png_ptr, (png_size_t)size));
-
-   else
-      ret = (png_malloc_default(png_ptr, size));
-
-   if (ret == NULL && (png_ptr->flags&PNG_FLAG_MALLOC_NULL_MEM_OK) == 0)
-       dg_png_error(png_ptr, "Out of Memory");
-
-   return (ret);
-}
-
-PNG_FUNCTION(png_voidp,PNGAPI
-png_malloc_default,(png_structp png_ptr, png_alloc_size_t size),PNG_ALLOCATED)
-{
-   png_voidp ret;
-#  endif /* PNG_USER_MEM_SUPPORTED */
-
-   if (png_ptr == NULL || size == 0)
-      return (NULL);
-
-#  ifdef PNG_MAX_MALLOC_64K
-   if (size > (png_uint_32)65536L)
-   {
-#    ifndef PNG_USER_MEM_SUPPORTED
-      if ((png_ptr->flags&PNG_FLAG_MALLOC_NULL_MEM_OK) == 0)
-         dg_png_error(png_ptr, "Cannot Allocate > 64K");
-
-      else
-#    endif
-         return NULL;
-   }
-#  endif
-
-   /* Check for overflow */
-#  if defined(__TURBOC__) && !defined(__FLAT__)
-
-   if (size != (unsigned long)size)
-      ret = NULL;
-
-   else
-      ret = farmalloc(size);
-
-#  else
-#    if defined(_MSC_VER) && defined(MAXSEG_64K)
-   if (size != (unsigned long)size)
-      ret = NULL;
-
-   else
-      ret = halloc(size, 1);
-
-#    else
-   if (size != (size_t)size)
-      ret = NULL;
-
-   else
-      ret = malloc((size_t)size);
-#    endif
-#  endif
-
-#  ifndef PNG_USER_MEM_SUPPORTED
-   if (ret == NULL && (png_ptr->flags&PNG_FLAG_MALLOC_NULL_MEM_OK) == 0)
-      dg_png_error(png_ptr, "Out of Memory");
-#  endif
-
-   return (ret);
-}
-
-/* Free a pointer allocated by png_malloc().  If ptr is NULL, return
- * without taking any action.
- */
-void PNGAPI
-png_free(png_structp png_ptr, png_voidp ptr)
-{
-   if (png_ptr == NULL || ptr == NULL)
-      return;
-
-#  ifdef PNG_USER_MEM_SUPPORTED
-   if (png_ptr->free_fn != NULL)
-   {
-      (*(png_ptr->free_fn))(png_ptr, ptr);
-      return;
-   }
-
-   else
-      png_free_default(png_ptr, ptr);
-}
-
-void PNGAPI
-png_free_default(png_structp png_ptr, png_voidp ptr)
-{
-   if (png_ptr == NULL || ptr == NULL)
-      return;
-
-#  endif /* PNG_USER_MEM_SUPPORTED */
-
-#  if defined(__TURBOC__) && !defined(__FLAT__)
-   farfree(ptr);
-
-#  else
-#    if defined(_MSC_VER) && defined(MAXSEG_64K)
-   hfree(ptr);
-
-#    else
-   free(ptr);
-
-#    endif
-#  endif
-}
-#endif /* Not Borland DOS special memory handler */
-
-/* This function was added at libpng version 1.2.3.  The png_malloc_warn()
- * function will set up png_malloc() to issue a png_warning and return NULL
- * instead of issuing a png_error, if it fails to allocate the requested
- * memory.
- */
-PNG_FUNCTION(png_voidp,PNGAPI
-png_malloc_warn,(png_structp png_ptr, png_alloc_size_t size),PNG_ALLOCATED)
-{
-   png_voidp ptr;
-   png_uint_32 save_flags;
-   if (png_ptr == NULL)
-      return (NULL);
-
-   save_flags = png_ptr->flags;
-   png_ptr->flags|=PNG_FLAG_MALLOC_NULL_MEM_OK;
-   ptr = (png_voidp)png_malloc((png_structp)png_ptr, size);
-   png_ptr->flags=save_flags;
-   return(ptr);
-}
-
-
-#ifdef PNG_USER_MEM_SUPPORTED
-/* This function is called when the application wants to use another method
- * of allocating and freeing memory.
- */
-void PNGAPI
-png_set_mem_fn(png_structp png_ptr, png_voidp mem_ptr, png_malloc_ptr
-  malloc_fn, png_free_ptr free_fn)
-{
-   if (png_ptr != NULL)
-   {
-      png_ptr->mem_ptr = mem_ptr;
-      png_ptr->malloc_fn = malloc_fn;
-      png_ptr->free_fn = free_fn;
-   }
-}
-
-/* This function returns a pointer to the mem_ptr associated with the user
- * functions.  The application should free any memory associated with this
- * pointer before png_write_destroy and png_read_destroy are called.
- */
-png_voidp PNGAPI
-png_get_mem_ptr(png_const_structp png_ptr)
-{
-   if (png_ptr == NULL)
-      return (NULL);
-
-   return ((png_voidp)png_ptr->mem_ptr);
-}
-#endif /* PNG_USER_MEM_SUPPORTED */
-#endif /* PNG_READ_SUPPORTED || PNG_WRITE_SUPPORTED */
diff --git a/plugingui/png/pngpriv.h b/plugingui/png/pngpriv.h
deleted file mode 100644
index dd35e52..0000000
--- a/plugingui/png/pngpriv.h
+++ /dev/null
@@ -1,1675 +0,0 @@
-
-/* pngpriv.h - private declarations for use inside libpng
- *
- * For conditions of distribution and use, see copyright notice in png.h
- * Copyright (c) 1998-2012 Glenn Randers-Pehrson
- * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
- * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)
- *
- * Last changed in libpng 1.5.10 [March 29, 2012]
- *
- * This code is released under the libpng license.
- * For conditions of distribution and use, see the disclaimer
- * and license in png.h
- */
-
-/* The symbols declared in this file (including the functions declared
- * as PNG_EXTERN) are PRIVATE.  They are not part of the libpng public
- * interface, and are not recommended for use by regular applications.
- * Some of them may become public in the future; others may stay private,
- * change in an incompatible way, or even disappear.
- * Although the libpng users are not forbidden to include this header,
- * they should be well aware of the issues that may arise from doing so.
- */
-
-#ifndef PNGPRIV_H
-#define PNGPRIV_H
-
-/* Feature Test Macros.  The following are defined here to ensure that correctly
- * implemented libraries reveal the APIs libpng needs to build and hide those
- * that are not needed and potentially damaging to the compilation.
- *
- * Feature Test Macros must be defined before any system header is included (see
- * POSIX 1003.1 2.8.2 "POSIX Symbols."
- *
- * These macros only have an effect if the operating system supports either
- * POSIX 1003.1 or C99, or both.  On other operating systems (particularly
- * Windows/Visual Studio) there is no effect; the OS specific tests below are
- * still required (as of 2011-05-02.)
- */
-#define _POSIX_SOURCE 1 /* Just the POSIX 1003.1 and C89 APIs */
-
-/* This is required for the definition of abort(), used as a last ditch
- * error handler when all else fails.
- */
-#include <stdlib.h>
-
-/* This is used to find 'offsetof', used below for alignment tests. */
-#include <stddef.h>
-
-#define PNGLIB_BUILD /*libpng is being built, not used*/
-
-#ifdef PNG_USER_CONFIG
-#  include "pngusr.h"
-   /* These should have been defined in pngusr.h */
-#  ifndef PNG_USER_PRIVATEBUILD
-#    define PNG_USER_PRIVATEBUILD "Custom libpng build"
-#  endif
-#  ifndef PNG_USER_DLLFNAME_POSTFIX
-#    define PNG_USER_DLLFNAME_POSTFIX "Cb"
-#  endif
-#endif
-
-/* Is this a build of a DLL where compilation of the object modules requires
- * different preprocessor settings to those required for a simple library?  If
- * so PNG_BUILD_DLL must be set.
- *
- * If libpng is used inside a DLL but that DLL does not export the libpng APIs
- * PNG_BUILD_DLL must not be set.  To avoid the code below kicking in build a
- * static library of libpng then link the DLL against that.
- */
-#ifndef PNG_BUILD_DLL
-#  ifdef DLL_EXPORT
-      /* This is set by libtool when files are compiled for a DLL; libtool
-       * always compiles twice, even on systems where it isn't necessary.  Set
-       * PNG_BUILD_DLL in case it is necessary:
-       */
-#     define PNG_BUILD_DLL
-#  else
-#     ifdef _WINDLL
-         /* This is set by the Microsoft Visual Studio IDE in projects that
-          * build a DLL.  It can't easily be removed from those projects (it
-          * isn't visible in the Visual Studio UI) so it is a fairly reliable
-          * indication that PNG_IMPEXP needs to be set to the DLL export
-          * attributes.
-          */
-#        define PNG_BUILD_DLL
-#     else
-#        ifdef __DLL__
-            /* This is set by the Borland C system when compiling for a DLL
-             * (as above.)
-             */
-#           define PNG_BUILD_DLL
-#        else
-            /* Add additional compiler cases here. */
-#        endif
-#     endif
-#  endif
-#endif /* Setting PNG_BUILD_DLL if required */
-
-/* See pngconf.h for more details: the builder of the library may set this on
- * the command line to the right thing for the specific compilation system or it
- * may be automagically set above (at present we know of no system where it does
- * need to be set on the command line.)
- *
- * PNG_IMPEXP must be set here when building the library to prevent pngconf.h
- * setting it to the "import" setting for a DLL build.
- */
-#ifndef PNG_IMPEXP
-#  ifdef PNG_BUILD_DLL
-#     define PNG_IMPEXP PNG_DLL_EXPORT
-#  else
-      /* Not building a DLL, or the DLL doesn't require specific export
-       * definitions.
-       */
-#     define PNG_IMPEXP
-#  endif
-#endif
-
-/* No warnings for private or deprecated functions in the build: */
-#ifndef PNG_DEPRECATED
-#  define PNG_DEPRECATED
-#endif
-#ifndef PNG_PRIVATE
-#  define PNG_PRIVATE
-#endif
-
-#include "png.h"
-#include "pnginfo.h"
-#include "pngstruct.h"
-
-/* pngconf.h does not set PNG_DLL_EXPORT unless it is required, so: */
-#ifndef PNG_DLL_EXPORT
-#  define PNG_DLL_EXPORT
-#endif
-
-/* SECURITY and SAFETY:
- *
- * By default libpng is built without any internal limits on image size,
- * individual heap (png_malloc) allocations or the total amount of memory used.
- * If PNG_SAFE_LIMITS_SUPPORTED is defined, however, the limits below are used
- * (unless individually overridden).  These limits are believed to be fairly
- * safe, but builders of secure systems should verify the values against the
- * real system capabilities.
- */
-
-#ifdef PNG_SAFE_LIMITS_SUPPORTED
-   /* 'safe' limits */
-#  ifndef PNG_USER_WIDTH_MAX
-#     define PNG_USER_WIDTH_MAX 1000000
-#  endif
-#  ifndef PNG_USER_HEIGHT_MAX
-#     define PNG_USER_HEIGHT_MAX 1000000
-#  endif
-#  ifndef PNG_USER_CHUNK_CACHE_MAX
-#     define PNG_USER_CHUNK_CACHE_MAX 128
-#  endif
-#  ifndef PNG_USER_CHUNK_MALLOC_MAX
-#     define PNG_USER_CHUNK_MALLOC_MAX 8000000
-#  endif
-#else
-   /* values for no limits */
-#  ifndef PNG_USER_WIDTH_MAX
-#     define PNG_USER_WIDTH_MAX 0x7fffffff
-#  endif
-#  ifndef PNG_USER_HEIGHT_MAX
-#     define PNG_USER_HEIGHT_MAX 0x7fffffff
-#  endif
-#  ifndef PNG_USER_CHUNK_CACHE_MAX
-#     define PNG_USER_CHUNK_CACHE_MAX 0
-#  endif
-#  ifndef PNG_USER_CHUNK_MALLOC_MAX
-#     define PNG_USER_CHUNK_MALLOC_MAX 0
-#  endif
-#endif
-
-/* This is used for 16 bit gamma tables - only the top level pointers are const,
- * this could be changed:
- */
-typedef PNG_CONST png_uint_16p FAR * png_const_uint_16pp;
-
-/* Added at libpng-1.2.9 */
-/* Moved to pngpriv.h at libpng-1.5.0 */
-
-/* config.h is created by and PNG_CONFIGURE_LIBPNG is set by the "configure"
- * script.  We may need it here to get the correct configuration on things
- * like limits.
- */
-#ifdef PNG_CONFIGURE_LIBPNG
-#  ifdef HAVE_CONFIG_H
-#    include "config.h"
-#  endif
-#endif
-
-/* Moved to pngpriv.h at libpng-1.5.0 */
-/* NOTE: some of these may have been used in external applications as
- * these definitions were exposed in pngconf.h prior to 1.5.
- */
-
-/* If you are running on a machine where you cannot allocate more
- * than 64K of memory at once, uncomment this.  While libpng will not
- * normally need that much memory in a chunk (unless you load up a very
- * large file), zlib needs to know how big of a chunk it can use, and
- * libpng thus makes sure to check any memory allocation to verify it
- * will fit into memory.
- *
- * zlib provides 'MAXSEG_64K' which, if defined, indicates the
- * same limit and pngconf.h (already included) sets the limit
- * if certain operating systems are detected.
- */
-#if defined(MAXSEG_64K) && !defined(PNG_MAX_MALLOC_64K)
-#  define PNG_MAX_MALLOC_64K
-#endif
-
-#ifndef PNG_UNUSED
-/* Unused formal parameter warnings are silenced using the following macro
- * which is expected to have no bad effects on performance (optimizing
- * compilers will probably remove it entirely).  Note that if you replace
- * it with something other than whitespace, you must include the terminating
- * semicolon.
- */
-#  define PNG_UNUSED(param) (void)param;
-#endif
-
-/* Just a little check that someone hasn't tried to define something
- * contradictory.
- */
-#if (PNG_ZBUF_SIZE > 65536L) && defined(PNG_MAX_MALLOC_64K)
-#  undef PNG_ZBUF_SIZE
-#  define PNG_ZBUF_SIZE 65536L
-#endif
-
-/* PNG_STATIC is used to mark internal file scope functions if they need to be
- * accessed for implementation tests (see the code in tests/?*).
- */
-#ifndef PNG_STATIC
-#   define PNG_STATIC static
-#endif
-
-/* C99 restrict is used where possible, to do this 'restrict' is defined as
- * empty if we can't be sure it is supported.  configure builds have already
- * done this work.
- */
-#ifdef PNG_CONFIGURE_LIBPNG
-#  define PNG_RESTRICT restrict
-#else
-   /* Modern compilers support restrict, but assume not for anything not
-    * recognized here:
-    */
-#  if defined __GNUC__ || defined _MSC_VER || defined __WATCOMC__
-#     define PNG_RESTRICT restrict
-#  else
-#     define PNG_RESTRICT
-#  endif
-#endif
-
-/* If warnings or errors are turned off the code is disabled or redirected here.
- * From 1.5.4 functions have been added to allow very limited formatting of
- * error and warning messages - this code will also be disabled here.
- */
-#ifdef PNG_WARNINGS_SUPPORTED
-#  define PNG_WARNING_PARAMETERS(p) png_warning_parameters p;
-#else
-#  define png_warning(s1,s2) ((void)(s1))
-#  define png_chunk_warning(s1,s2) ((void)(s1))
-#  define png_warning_parameter(p,number,string) ((void)0)
-#  define png_warning_parameter_unsigned(p,number,format,value) ((void)0)
-#  define png_warning_parameter_signed(p,number,format,value) ((void)0)
-#  define png_formatted_warning(pp,p,message) ((void)(pp))
-#  define PNG_WARNING_PARAMETERS(p)
-#endif
-#ifndef PNG_ERROR_TEXT_SUPPORTED
-#  define png_error(s1,s2) png_err(s1)
-#  define png_chunk_error(s1,s2) png_err(s1)
-#  define png_fixed_error(s1,s2) png_err(s1)
-#endif
-
-/* C allows up-casts from (void*) to any pointer and (const void*) to any
- * pointer to a const object.  C++ regards this as a type error and requires an
- * explicit, static, cast and provides the static_cast<> rune to ensure that
- * const is not cast away.
- */
-#ifdef __cplusplus
-#  define png_voidcast(type, value) static_cast<type>(value)
-#else
-#  define png_voidcast(type, value) (value)
-#endif /* __cplusplus */
-
-#ifndef PNG_EXTERN
-/* The functions exported by PNG_EXTERN are internal functions, which
- * aren't usually used outside the library (as far as I know), so it is
- * debatable if they should be exported at all.  In the future, when it
- * is possible to have run-time registry of chunk-handling functions,
- * some of these might be made available again.
- *
- * 1.5.7: turned the use of 'extern' back on, since it is localized to pngpriv.h
- * it should be safe now (it is unclear why it was turned off.)
- */
-#  define PNG_EXTERN extern
-#endif
-
-/* Some fixed point APIs are still required even if not exported because
- * they get used by the corresponding floating point APIs.  This magic
- * deals with this:
- */
-#ifdef PNG_FIXED_POINT_SUPPORTED
-#  define PNGFAPI PNGAPI
-#else
-#  define PNGFAPI /* PRIVATE */
-#endif
-
-/* Other defines specific to compilers can go here.  Try to keep
- * them inside an appropriate ifdef/endif pair for portability.
- */
-#if defined(PNG_FLOATING_POINT_SUPPORTED) ||\
-    defined(PNG_FLOATING_ARITHMETIC_SUPPORTED)
-   /* png.c requires the following ANSI-C constants if the conversion of
-    * floating point to ASCII is implemented therein:
-    *
-    *  DBL_DIG  Maximum number of decimal digits (can be set to any constant)
-    *  DBL_MIN  Smallest normalized fp number (can be set to an arbitrary value)
-    *  DBL_MAX  Maximum floating point number (can be set to an arbitrary value)
-    */
-#  include <float.h>
-
-#  if (defined(__MWERKS__) && defined(macintosh)) || defined(applec) || \
-    defined(THINK_C) || defined(__SC__) || defined(TARGET_OS_MAC)
-     /* We need to check that <math.h> hasn't already been included earlier
-      * as it seems it doesn't agree with <fp.h>, yet we should really use
-      * <fp.h> if possible.
-      */
-#    if !defined(__MATH_H__) && !defined(__MATH_H) && !defined(__cmath__)
-#      include <fp.h>
-#    endif
-#  else
-#    include <math.h>
-#  endif
-#  if defined(_AMIGA) && defined(__SASC) && defined(_M68881)
-     /* Amiga SAS/C: We must include builtin FPU functions when compiling using
-      * MATH=68881
-      */
-#    include <m68881.h>
-#  endif
-#endif
-
-/* This provides the non-ANSI (far) memory allocation routines. */
-#if defined(__TURBOC__) && defined(__MSDOS__)
-#  include <mem.h>
-#  include <alloc.h>
-#endif
-
-#if defined(WIN32) || defined(_Windows) || defined(_WINDOWS) || \
-    defined(_WIN32) || defined(__WIN32__)
-#  include <windows.h>  /* defines _WINDOWS_ macro */
-#endif
-
-/* Moved here around 1.5.0beta36 from pngconf.h */
-/* Users may want to use these so they are not private.  Any library
- * functions that are passed far data must be model-independent.
- */
-
-/* Memory model/platform independent fns */
-#ifndef PNG_ABORT
-#  ifdef _WINDOWS_
-#    define PNG_ABORT() ExitProcess(0)
-#  else
-#    define PNG_ABORT() abort()
-#  endif
-#endif
-
-#ifdef USE_FAR_KEYWORD
-/* Use this to make far-to-near assignments */
-#  define CHECK   1
-#  define NOCHECK 0
-#  define CVT_PTR(ptr) (png_far_to_near(png_ptr,ptr,CHECK))
-#  define CVT_PTR_NOCHECK(ptr) (png_far_to_near(png_ptr,ptr,NOCHECK))
-#  define png_strlen  _fstrlen
-#  define png_memcmp  _fmemcmp    /* SJT: added */
-#  define png_memcpy  _fmemcpy
-#  define png_memset  _fmemset
-#else
-#  ifdef _WINDOWS_  /* Favor Windows over C runtime fns */
-#    define CVT_PTR(ptr)         (ptr)
-#    define CVT_PTR_NOCHECK(ptr) (ptr)
-#    define png_strlen  lstrlenA
-#    define png_memcmp  memcmp
-#    define png_memcpy  CopyMemory
-#    define png_memset  memset
-#  else
-#    define CVT_PTR(ptr)         (ptr)
-#    define CVT_PTR_NOCHECK(ptr) (ptr)
-#    define png_strlen  strlen
-#    define png_memcmp  memcmp      /* SJT: added */
-#    define png_memcpy  memcpy
-#    define png_memset  memset
-#  endif
-#endif
-
-/* These macros may need to be architecture dependent. */
-#define PNG_ALIGN_NONE   0 /* do not use data alignment */
-#define PNG_ALIGN_ALWAYS 1 /* assume unaligned accesses are OK */
-#ifdef offsetof
-#  define PNG_ALIGN_OFFSET 2 /* use offsetof to determine alignment */
-#else
-#  define PNG_ALIGN_OFFSET -1 /* prevent the use of this */
-#endif
-#define PNG_ALIGN_SIZE   3 /* use sizeof to determine alignment */
-
-#ifndef PNG_ALIGN_TYPE
-   /* Default to using aligned access optimizations and requiring alignment to a
-    * multiple of the data type size.  Override in a compiler specific fashion
-    * if necessary by inserting tests here:
-    */
-#  define PNG_ALIGN_TYPE PNG_ALIGN_SIZE
-#endif
-
-#if PNG_ALIGN_TYPE == PNG_ALIGN_SIZE
-   /* This is used because in some compiler implementations non-aligned
-    * structure members are supported, so the offsetof approach below fails.
-    * Set PNG_ALIGN_TO_SIZE=0 for compiler combinations where unaligned access
-    * is good for performance.  Do not do this unless you have tested the result
-    * and understand it.
-    */
-#  define png_alignof(type) (sizeof (type))
-#else
-#  if PNG_ALIGN_TYPE == PNG_ALIGN_OFFSET
-#     define png_alignof(type) offsetof(struct{char c; type t;}, t)
-#  else
-#     if PNG_ALIGN_TYPE == PNG_ALIGN_ALWAYS
-#        define png_alignof(type) (1)
-#     endif
-      /* Else leave png_alignof undefined to prevent use thereof */
-#  endif
-#endif
-
-/* This implicitly assumes alignment is always to a power of 2. */
-#ifdef png_alignof
-#  define png_isaligned(ptr, type)\
-   ((((const char*)ptr-(const char*)0) & (png_alignof(type)-1)) == 0)
-#else
-#  define png_isaligned(ptr, type) 0
-#endif
-
-/* End of memory model/platform independent support */
-/* End of 1.5.0beta36 move from pngconf.h */
-
-/* CONSTANTS and UTILITY MACROS
- * These are used internally by libpng and not exposed in the API
- */
-
-/* Various modes of operation.  Note that after an init, mode is set to
- * zero automatically when the structure is created.  Three of these
- * are defined in png.h because they need to be visible to applications
- * that call png_set_unknown_chunk().
- */
-/* #define PNG_HAVE_IHDR            0x01 (defined in png.h) */
-/* #define PNG_HAVE_PLTE            0x02 (defined in png.h) */
-#define PNG_HAVE_IDAT               0x04
-/* #define PNG_AFTER_IDAT           0x08 (defined in png.h) */
-#define PNG_HAVE_IEND               0x10
-#define PNG_HAVE_gAMA               0x20
-#define PNG_HAVE_cHRM               0x40
-#define PNG_HAVE_sRGB               0x80
-#define PNG_HAVE_CHUNK_HEADER      0x100
-#define PNG_WROTE_tIME             0x200
-#define PNG_WROTE_INFO_BEFORE_PLTE 0x400
-#define PNG_BACKGROUND_IS_GRAY     0x800
-#define PNG_HAVE_PNG_SIGNATURE    0x1000
-#define PNG_HAVE_CHUNK_AFTER_IDAT 0x2000 /* Have another chunk after IDAT */
-#define PNG_HAVE_iCCP             0x4000
-
-/* Flags for the transformations the PNG library does on the image data */
-#define PNG_BGR                 0x0001
-#define PNG_INTERLACE           0x0002
-#define PNG_PACK                0x0004
-#define PNG_SHIFT               0x0008
-#define PNG_SWAP_BYTES          0x0010
-#define PNG_INVERT_MONO         0x0020
-#define PNG_QUANTIZE            0x0040
-#define PNG_COMPOSE             0x0080     /* Was PNG_BACKGROUND */
-#define PNG_BACKGROUND_EXPAND   0x0100
-#define PNG_EXPAND_16           0x0200     /* Added to libpng 1.5.2 */
-#define PNG_16_TO_8             0x0400     /* Becomes 'chop' in 1.5.4 */
-#define PNG_RGBA                0x0800
-#define PNG_EXPAND              0x1000
-#define PNG_GAMMA               0x2000
-#define PNG_GRAY_TO_RGB         0x4000
-#define PNG_FILLER              0x8000
-#define PNG_PACKSWAP           0x10000
-#define PNG_SWAP_ALPHA         0x20000
-#define PNG_STRIP_ALPHA        0x40000
-#define PNG_INVERT_ALPHA       0x80000
-#define PNG_USER_TRANSFORM    0x100000
-#define PNG_RGB_TO_GRAY_ERR   0x200000
-#define PNG_RGB_TO_GRAY_WARN  0x400000
-#define PNG_RGB_TO_GRAY       0x600000 /* two bits, RGB_TO_GRAY_ERR|WARN */
-#define PNG_ENCODE_ALPHA      0x800000 /* Added to libpng-1.5.4 */
-#define PNG_ADD_ALPHA         0x1000000 /* Added to libpng-1.2.7 */
-#define PNG_EXPAND_tRNS       0x2000000 /* Added to libpng-1.2.9 */
-#define PNG_SCALE_16_TO_8     0x4000000 /* Added to libpng-1.5.4 */
-                       /*   0x8000000 unused */
-                       /*  0x10000000 unused */
-                       /*  0x20000000 unused */
-                       /*  0x40000000 unused */
-/* Flags for png_create_struct */
-#define PNG_STRUCT_PNG   0x0001
-#define PNG_STRUCT_INFO  0x0002
-
-/* Scaling factor for filter heuristic weighting calculations */
-#define PNG_WEIGHT_FACTOR (1<<(PNG_WEIGHT_SHIFT))
-#define PNG_COST_FACTOR (1<<(PNG_COST_SHIFT))
-
-/* Flags for the png_ptr->flags rather than declaring a byte for each one */
-#define PNG_FLAG_ZLIB_CUSTOM_STRATEGY     0x0001
-#define PNG_FLAG_ZLIB_CUSTOM_LEVEL        0x0002
-#define PNG_FLAG_ZLIB_CUSTOM_MEM_LEVEL    0x0004
-#define PNG_FLAG_ZLIB_CUSTOM_WINDOW_BITS  0x0008
-#define PNG_FLAG_ZLIB_CUSTOM_METHOD       0x0010
-#define PNG_FLAG_ZLIB_FINISHED            0x0020
-#define PNG_FLAG_ROW_INIT                 0x0040
-#define PNG_FLAG_FILLER_AFTER             0x0080
-#define PNG_FLAG_CRC_ANCILLARY_USE        0x0100
-#define PNG_FLAG_CRC_ANCILLARY_NOWARN     0x0200
-#define PNG_FLAG_CRC_CRITICAL_USE         0x0400
-#define PNG_FLAG_CRC_CRITICAL_IGNORE      0x0800
-#define PNG_FLAG_ASSUME_sRGB              0x1000  /* Added to libpng-1.5.4 */
-#define PNG_FLAG_OPTIMIZE_ALPHA           0x2000  /* Added to libpng-1.5.4 */
-#define PNG_FLAG_DETECT_UNINITIALIZED     0x4000  /* Added to libpng-1.5.4 */
-#define PNG_FLAG_KEEP_UNKNOWN_CHUNKS      0x8000
-#define PNG_FLAG_KEEP_UNSAFE_CHUNKS       0x10000
-#define PNG_FLAG_LIBRARY_MISMATCH         0x20000
-#define PNG_FLAG_STRIP_ERROR_NUMBERS      0x40000
-#define PNG_FLAG_STRIP_ERROR_TEXT         0x80000
-#define PNG_FLAG_MALLOC_NULL_MEM_OK       0x100000
-                                  /*      0x200000  unused */
-                                  /*      0x400000  unused */
-#define PNG_FLAG_BENIGN_ERRORS_WARN       0x800000  /* Added to libpng-1.4.0 */
-#define PNG_FLAG_ZTXT_CUSTOM_STRATEGY    0x1000000  /* 5 lines added */
-#define PNG_FLAG_ZTXT_CUSTOM_LEVEL       0x2000000  /* to libpng-1.5.4 */
-#define PNG_FLAG_ZTXT_CUSTOM_MEM_LEVEL   0x4000000
-#define PNG_FLAG_ZTXT_CUSTOM_WINDOW_BITS 0x8000000
-#define PNG_FLAG_ZTXT_CUSTOM_METHOD      0x10000000
-                                  /*     0x20000000  unused */
-                                  /*     0x40000000  unused */
-
-#define PNG_FLAG_CRC_ANCILLARY_MASK (PNG_FLAG_CRC_ANCILLARY_USE | \
-                                     PNG_FLAG_CRC_ANCILLARY_NOWARN)
-
-#define PNG_FLAG_CRC_CRITICAL_MASK  (PNG_FLAG_CRC_CRITICAL_USE | \
-                                     PNG_FLAG_CRC_CRITICAL_IGNORE)
-
-#define PNG_FLAG_CRC_MASK           (PNG_FLAG_CRC_ANCILLARY_MASK | \
-                                     PNG_FLAG_CRC_CRITICAL_MASK)
-
-/* zlib.h declares a magic type 'uInt' that limits the amount of data that zlib
- * can handle at once.  This type need be no larger than 16 bits (so maximum of
- * 65535), this define allows us to discover how big it is, but limited by the
- * maximuum for png_size_t.  The value can be overriden in a library build
- * (pngusr.h, or set it in CPPFLAGS) and it works to set it to a considerably
- * lower value (e.g. 255 works).  A lower value may help memory usage (slightly)
- * and may even improve performance on some systems (and degrade it on others.)
- */
-#ifndef ZLIB_IO_MAX
-#  define ZLIB_IO_MAX ((uInt)-1)
-#endif
-
-/* Save typing and make code easier to understand */
-
-#define PNG_COLOR_DIST(c1, c2) (abs((int)((c1).red) - (int)((c2).red)) + \
-   abs((int)((c1).green) - (int)((c2).green)) + \
-   abs((int)((c1).blue) - (int)((c2).blue)))
-
-/* Added to libpng-1.2.6 JB */
-#define PNG_ROWBYTES(pixel_bits, width) \
-    ((pixel_bits) >= 8 ? \
-    ((png_size_t)(width) * (((png_size_t)(pixel_bits)) >> 3)) : \
-    (( ((png_size_t)(width) * ((png_size_t)(pixel_bits))) + 7) >> 3) )
-
-/* PNG_OUT_OF_RANGE returns true if value is outside the range
- * ideal-delta..ideal+delta.  Each argument is evaluated twice.
- * "ideal" and "delta" should be constants, normally simple
- * integers, "value" a variable. Added to libpng-1.2.6 JB
- */
-#define PNG_OUT_OF_RANGE(value, ideal, delta) \
-   ( (value) < (ideal)-(delta) || (value) > (ideal)+(delta) )
-
-/* Conversions between fixed and floating point, only defined if
- * required (to make sure the code doesn't accidentally use float
- * when it is supposedly disabled.)
- */
-#ifdef PNG_FLOATING_POINT_SUPPORTED
-/* The floating point conversion can't overflow, though it can and
- * does lose accuracy relative to the original fixed point value.
- * In practice this doesn't matter because png_fixed_point only
- * stores numbers with very low precision.  The png_ptr and s
- * arguments are unused by default but are there in case error
- * checking becomes a requirement.
- */
-#define png_float(png_ptr, fixed, s) (.00001 * (fixed))
-
-/* The fixed point conversion performs range checking and evaluates
- * its argument multiple times, so must be used with care.  The
- * range checking uses the PNG specification values for a signed
- * 32 bit fixed point value except that the values are deliberately
- * rounded-to-zero to an integral value - 21474 (21474.83 is roughly
- * (2^31-1) * 100000). 's' is a string that describes the value being
- * converted.
- *
- * NOTE: this macro will raise a png_error if the range check fails,
- * therefore it is normally only appropriate to use this on values
- * that come from API calls or other sources where an out of range
- * error indicates a programming error, not a data error!
- *
- * NOTE: by default this is off - the macro is not used - because the
- * function call saves a lot of code.
- */
-#ifdef PNG_FIXED_POINT_MACRO_SUPPORTED
-#define png_fixed(png_ptr, fp, s) ((fp) <= 21474 && (fp) >= -21474 ?\
-    ((png_fixed_point)(100000 * (fp))) : (png_fixed_error(png_ptr, s),0))
-#else
-PNG_EXTERN png_fixed_point png_fixed PNGARG((png_structp png_ptr, double fp,
-   png_const_charp text));
-#endif
-#endif
-
-/* Constants for known chunk types.  If you need to add a chunk, define the name
- * here.  For historical reasons these constants have the form png_<name>; i.e.
- * the prefix is lower case.  Please use decimal values as the parameters to
- * match the ISO PNG specification and to avoid relying on the C locale
- * interpretation of character values.
- *
- * Prior to 1.5.6 these constants were strings, as of 1.5.6 png_uint_32 values
- * are computed and a new macro (PNG_STRING_FROM_CHUNK) added to allow a string
- * to be generated if required.
- *
- * PNG_32b correctly produces a value shifted by up to 24 bits, even on
- * architectures where (int) is only 16 bits.
- */
-#define PNG_32b(b,s) ((png_uint_32)(b) << (s))
-#define PNG_CHUNK(b1,b2,b3,b4) \
-   (PNG_32b(b1,24) | PNG_32b(b2,16) | PNG_32b(b3,8) | PNG_32b(b4,0))
-
-#define png_IHDR PNG_CHUNK( 73,  72,  68,  82)
-#define png_IDAT PNG_CHUNK( 73,  68,  65,  84)
-#define png_IEND PNG_CHUNK( 73,  69,  78,  68)
-#define png_PLTE PNG_CHUNK( 80,  76,  84,  69)
-#define png_bKGD PNG_CHUNK( 98,  75,  71,  68)
-#define png_cHRM PNG_CHUNK( 99,  72,  82,  77)
-#define png_gAMA PNG_CHUNK(103,  65,  77,  65)
-#define png_hIST PNG_CHUNK(104,  73,  83,  84)
-#define png_iCCP PNG_CHUNK(105,  67,  67,  80)
-#define png_iTXt PNG_CHUNK(105,  84,  88, 116)
-#define png_oFFs PNG_CHUNK(111,  70,  70, 115)
-#define png_pCAL PNG_CHUNK(112,  67,  65,  76)
-#define png_sCAL PNG_CHUNK(115,  67,  65,  76)
-#define png_pHYs PNG_CHUNK(112,  72,  89, 115)
-#define png_sBIT PNG_CHUNK(115,  66,  73,  84)
-#define png_sPLT PNG_CHUNK(115,  80,  76,  84)
-#define png_sRGB PNG_CHUNK(115,  82,  71,  66)
-#define png_sTER PNG_CHUNK(115,  84,  69,  82)
-#define png_tEXt PNG_CHUNK(116,  69,  88, 116)
-#define png_tIME PNG_CHUNK(116,  73,  77,  69)
-#define png_tRNS PNG_CHUNK(116,  82,  78,  83)
-#define png_zTXt PNG_CHUNK(122,  84,  88, 116)
-
-/* The following will work on (signed char*) strings, whereas the get_uint_32
- * macro will fail on top-bit-set values because of the sign extension.
- */
-#define PNG_CHUNK_FROM_STRING(s)\
-   PNG_CHUNK(0xff&(s)[0], 0xff&(s)[1], 0xff&(s)[2], 0xff&(s)[3])
-
-/* This uses (char), not (png_byte) to avoid warnings on systems where (char) is
- * signed and the argument is a (char[])  This macro will fail miserably on
- * systems where (char) is more than 8 bits.
- */
-#define PNG_STRING_FROM_CHUNK(s,c)\
-   (void)(((char*)(s))[0]=(char)((c)>>24), ((char*)(s))[1]=(char)((c)>>16),\
-   ((char*)(s))[2]=(char)((c)>>8), ((char*)(s))[3]=(char)((c)))
-
-/* Do the same but terminate with a null character. */
-#define PNG_CSTRING_FROM_CHUNK(s,c)\
-   (void)(PNG_STRING_FROM_CHUNK(s,c), ((char*)(s))[4] = 0)
-
-/* Test on flag values as defined in the spec (section 5.4): */
-#define PNG_CHUNK_ANCILLIARY(c)   (1 & ((c) >> 29))
-#define PNG_CHUNK_CRITICAL(c)     (!PNG_CHUNK_ANCILLIARY(c))
-#define PNG_CHUNK_PRIVATE(c)      (1 & ((c) >> 21))
-#define PNG_CHUNK_RESERVED(c)     (1 & ((c) >> 13))
-#define PNG_CHUNK_SAFE_TO_COPY(c) (1 & ((c) >>  5))
-
-/* Gamma values (new at libpng-1.5.4): */
-#define PNG_GAMMA_MAC_OLD 151724  /* Assume '1.8' is really 2.2/1.45! */
-#define PNG_GAMMA_MAC_INVERSE 65909
-#define PNG_GAMMA_sRGB_INVERSE 45455
-
-
-/* Inhibit C++ name-mangling for libpng functions but not for system calls. */
-#ifdef __cplusplus
-extern "C" {
-#endif /* __cplusplus */
-
-/* These functions are used internally in the code.  They generally
- * shouldn't be used unless you are writing code to add or replace some
- * functionality in libpng.  More information about most functions can
- * be found in the files where the functions are located.
- */
-
-/* Check the user version string for compatibility, returns false if the version
- * numbers aren't compatible.
- */
-PNG_EXTERN int png_user_version_check(png_structp png_ptr,
-   png_const_charp user_png_ver);
-
-/* Allocate memory for an internal libpng struct */
-PNG_EXTERN PNG_FUNCTION(png_voidp,png_create_struct,PNGARG((int type)),
-   PNG_ALLOCATED);
-
-/* Free memory from internal libpng struct */
-PNG_EXTERN void png_destroy_struct PNGARG((png_voidp struct_ptr));
-
-PNG_EXTERN PNG_FUNCTION(png_voidp,png_create_struct_2,
-   PNGARG((int type, png_malloc_ptr malloc_fn, png_voidp mem_ptr)),
-   PNG_ALLOCATED);
-PNG_EXTERN void png_destroy_struct_2 PNGARG((png_voidp struct_ptr,
-    png_free_ptr free_fn, png_voidp mem_ptr));
-
-/* Free any memory that info_ptr points to and reset struct. */
-PNG_EXTERN void png_info_destroy PNGARG((png_structp png_ptr,
-    png_infop info_ptr));
-
-/* Function to allocate memory for zlib.  PNGAPI is disallowed. */
-PNG_EXTERN PNG_FUNCTION(voidpf,png_zalloc,PNGARG((voidpf png_ptr, uInt items,
-   uInt size)),PNG_ALLOCATED);
-
-/* Function to free memory for zlib.  PNGAPI is disallowed. */
-PNG_EXTERN void png_zfree PNGARG((voidpf png_ptr, voidpf ptr));
-
-/* Next four functions are used internally as callbacks.  PNGCBAPI is required
- * but not PNG_EXPORT.  PNGAPI added at libpng version 1.2.3, changed to
- * PNGCBAPI at 1.5.0
- */
-
-PNG_EXTERN void PNGCBAPI png_default_read_data PNGARG((png_structp png_ptr,
-    png_bytep data, png_size_t length));
-
-#ifdef PNG_PROGRESSIVE_READ_SUPPORTED
-PNG_EXTERN void PNGCBAPI png_push_fill_buffer PNGARG((png_structp png_ptr,
-    png_bytep buffer, png_size_t length));
-#endif
-
-PNG_EXTERN void PNGCBAPI png_default_write_data PNGARG((png_structp png_ptr,
-    png_bytep data, png_size_t length));
-
-#ifdef PNG_WRITE_FLUSH_SUPPORTED
-#  ifdef PNG_STDIO_SUPPORTED
-PNG_EXTERN void PNGCBAPI png_default_flush PNGARG((png_structp png_ptr));
-#  endif
-#endif
-
-/* Reset the CRC variable */
-PNG_EXTERN void png_reset_crc PNGARG((png_structp png_ptr));
-
-/* Write the "data" buffer to whatever output you are using */
-PNG_EXTERN void png_write_data PNGARG((png_structp png_ptr,
-    png_const_bytep data, png_size_t length));
-
-/* Read and check the PNG file signature */
-PNG_EXTERN void png_read_sig PNGARG((png_structp png_ptr, png_infop info_ptr));
-
-/* Read the chunk header (length + type name) */
-PNG_EXTERN png_uint_32 png_read_chunk_header PNGARG((png_structp png_ptr));
-
-/* Read data from whatever input you are using into the "data" buffer */
-PNG_EXTERN void png_read_data PNGARG((png_structp png_ptr, png_bytep data,
-    png_size_t length));
-
-/* Read bytes into buf, and update png_ptr->crc */
-PNG_EXTERN void png_crc_read PNGARG((png_structp png_ptr, png_bytep buf,
-    png_size_t length));
-
-/* Decompress data in a chunk that uses compression */
-#if defined(PNG_READ_COMPRESSED_TEXT_SUPPORTED)
-PNG_EXTERN void png_decompress_chunk PNGARG((png_structp png_ptr,
-    int comp_type, png_size_t chunklength, png_size_t prefix_length,
-    png_size_t *data_length));
-#endif
-
-/* Read "skip" bytes, read the file crc, and (optionally) verify png_ptr->crc */
-PNG_EXTERN int png_crc_finish PNGARG((png_structp png_ptr, png_uint_32 skip));
-
-/* Read the CRC from the file and compare it to the libpng calculated CRC */
-PNG_EXTERN int png_crc_error PNGARG((png_structp png_ptr));
-
-/* Calculate the CRC over a section of data.  Note that we are only
- * passing a maximum of 64K on systems that have this as a memory limit,
- * since this is the maximum buffer size we can specify.
- */
-PNG_EXTERN void png_calculate_crc PNGARG((png_structp png_ptr,
-    png_const_bytep ptr, png_size_t length));
-
-#ifdef PNG_WRITE_FLUSH_SUPPORTED
-PNG_EXTERN void png_flush PNGARG((png_structp png_ptr));
-#endif
-
-/* Write various chunks */
-
-/* Write the IHDR chunk, and update the png_struct with the necessary
- * information.
- */
-PNG_EXTERN void png_write_IHDR PNGARG((png_structp png_ptr, png_uint_32 width,
-    png_uint_32 height,
-    int bit_depth, int color_type, int compression_method, int filter_method,
-    int interlace_method));
-
-PNG_EXTERN void png_write_PLTE PNGARG((png_structp png_ptr,
-    png_const_colorp palette, png_uint_32 num_pal));
-
-PNG_EXTERN void png_write_IDAT PNGARG((png_structp png_ptr, png_bytep data,
-    png_size_t length));
-
-PNG_EXTERN void png_write_IEND PNGARG((png_structp png_ptr));
-
-#ifdef PNG_WRITE_gAMA_SUPPORTED
-#  ifdef PNG_FLOATING_POINT_SUPPORTED
-PNG_EXTERN void png_write_gAMA PNGARG((png_structp png_ptr, double file_gamma));
-#  endif
-#  ifdef PNG_FIXED_POINT_SUPPORTED
-PNG_EXTERN void png_write_gAMA_fixed PNGARG((png_structp png_ptr,
-    png_fixed_point file_gamma));
-#  endif
-#endif
-
-#ifdef PNG_WRITE_sBIT_SUPPORTED
-PNG_EXTERN void png_write_sBIT PNGARG((png_structp png_ptr,
-    png_const_color_8p sbit, int color_type));
-#endif
-
-#ifdef PNG_WRITE_cHRM_SUPPORTED
-#  ifdef PNG_FLOATING_POINT_SUPPORTED
-PNG_EXTERN void png_write_cHRM PNGARG((png_structp png_ptr,
-    double white_x, double white_y,
-    double red_x, double red_y, double green_x, double green_y,
-    double blue_x, double blue_y));
-#  endif
-PNG_EXTERN void png_write_cHRM_fixed PNGARG((png_structp png_ptr,
-    png_fixed_point int_white_x, png_fixed_point int_white_y,
-    png_fixed_point int_red_x, png_fixed_point int_red_y, png_fixed_point
-    int_green_x, png_fixed_point int_green_y, png_fixed_point int_blue_x,
-    png_fixed_point int_blue_y));
-#endif
-
-#ifdef PNG_WRITE_sRGB_SUPPORTED
-PNG_EXTERN void png_write_sRGB PNGARG((png_structp png_ptr,
-    int intent));
-#endif
-
-#ifdef PNG_WRITE_iCCP_SUPPORTED
-PNG_EXTERN void png_write_iCCP PNGARG((png_structp png_ptr,
-    png_const_charp name, int compression_type,
-    png_const_charp profile, int proflen));
-   /* Note to maintainer: profile should be png_bytep */
-#endif
-
-#ifdef PNG_WRITE_sPLT_SUPPORTED
-PNG_EXTERN void png_write_sPLT PNGARG((png_structp png_ptr,
-    png_const_sPLT_tp palette));
-#endif
-
-#ifdef PNG_WRITE_tRNS_SUPPORTED
-PNG_EXTERN void png_write_tRNS PNGARG((png_structp png_ptr,
-    png_const_bytep trans, png_const_color_16p values, int number,
-    int color_type));
-#endif
-
-#ifdef PNG_WRITE_bKGD_SUPPORTED
-PNG_EXTERN void png_write_bKGD PNGARG((png_structp png_ptr,
-    png_const_color_16p values, int color_type));
-#endif
-
-#ifdef PNG_WRITE_hIST_SUPPORTED
-PNG_EXTERN void png_write_hIST PNGARG((png_structp png_ptr,
-    png_const_uint_16p hist, int num_hist));
-#endif
-
-/* Chunks that have keywords */
-#if defined(PNG_WRITE_TEXT_SUPPORTED) || defined(PNG_WRITE_pCAL_SUPPORTED) || \
-    defined(PNG_WRITE_iCCP_SUPPORTED) || defined(PNG_WRITE_sPLT_SUPPORTED)
-PNG_EXTERN png_size_t png_check_keyword PNGARG((png_structp png_ptr,
-    png_const_charp key, png_charpp new_key));
-#endif
-
-#ifdef PNG_WRITE_tEXt_SUPPORTED
-PNG_EXTERN void png_write_tEXt PNGARG((png_structp png_ptr, png_const_charp key,
-    png_const_charp text, png_size_t text_len));
-#endif
-
-#ifdef PNG_WRITE_zTXt_SUPPORTED
-PNG_EXTERN void png_write_zTXt PNGARG((png_structp png_ptr, png_const_charp key,
-    png_const_charp text, png_size_t text_len, int compression));
-#endif
-
-#ifdef PNG_WRITE_iTXt_SUPPORTED
-PNG_EXTERN void png_write_iTXt PNGARG((png_structp png_ptr,
-    int compression, png_const_charp key, png_const_charp lang,
-    png_const_charp lang_key, png_const_charp text));
-#endif
-
-#ifdef PNG_TEXT_SUPPORTED  /* Added at version 1.0.14 and 1.2.4 */
-PNG_EXTERN int png_set_text_2 PNGARG((png_structp png_ptr,
-    png_infop info_ptr, png_const_textp text_ptr, int num_text));
-#endif
-
-#ifdef PNG_WRITE_oFFs_SUPPORTED
-PNG_EXTERN void png_write_oFFs PNGARG((png_structp png_ptr,
-    png_int_32 x_offset, png_int_32 y_offset, int unit_type));
-#endif
-
-#ifdef PNG_WRITE_pCAL_SUPPORTED
-PNG_EXTERN void png_write_pCAL PNGARG((png_structp png_ptr, png_charp purpose,
-    png_int_32 X0, png_int_32 X1, int type, int nparams,
-    png_const_charp units, png_charpp params));
-#endif
-
-#ifdef PNG_WRITE_pHYs_SUPPORTED
-PNG_EXTERN void png_write_pHYs PNGARG((png_structp png_ptr,
-    png_uint_32 x_pixels_per_unit, png_uint_32 y_pixels_per_unit,
-    int unit_type));
-#endif
-
-#ifdef PNG_WRITE_tIME_SUPPORTED
-PNG_EXTERN void png_write_tIME PNGARG((png_structp png_ptr,
-    png_const_timep mod_time));
-#endif
-
-#ifdef PNG_WRITE_sCAL_SUPPORTED
-PNG_EXTERN void png_write_sCAL_s PNGARG((png_structp png_ptr,
-    int unit, png_const_charp width, png_const_charp height));
-#endif
-
-/* Called when finished processing a row of data */
-PNG_EXTERN void png_write_finish_row PNGARG((png_structp png_ptr));
-
-/* Internal use only.   Called before first row of data */
-PNG_EXTERN void png_write_start_row PNGARG((png_structp png_ptr));
-
-/* Combine a row of data, dealing with alpha, etc. if requested.  'row' is an
- * array of png_ptr->width pixels.  If the image is not interlaced or this
- * is the final pass this just does a png_memcpy, otherwise the "display" flag
- * is used to determine whether to copy pixels that are not in the current pass.
- *
- * Because 'png_do_read_interlace' (below) replicates pixels this allows this
- * function to achieve the documented 'blocky' appearance during interlaced read
- * if display is 1 and the 'sparkle' appearance, where existing pixels in 'row'
- * are not changed if they are not in the current pass, when display is 0.
- *
- * 'display' must be 0 or 1, otherwise the memcpy will be done regardless.
- *
- * The API always reads from the png_struct row buffer and always assumes that
- * it is full width (png_do_read_interlace has already been called.)
- *
- * This function is only ever used to write to row buffers provided by the
- * caller of the relevant libpng API and the row must have already been
- * transformed by the read transformations.
- *
- * The PNG_USE_COMPILE_TIME_MASKS option causes generation of pre-computed
- * bitmasks for use within the code, otherwise runtime generated masks are used.
- * The default is compile time masks.
- */
-#ifndef PNG_USE_COMPILE_TIME_MASKS
-#  define PNG_USE_COMPILE_TIME_MASKS 1
-#endif
-PNG_EXTERN void png_combine_row PNGARG((png_structp png_ptr, png_bytep row,
-    int display));
-
-#ifdef PNG_READ_INTERLACING_SUPPORTED
-/* Expand an interlaced row: the 'row_info' describes the pass data that has
- * been read in and must correspond to the pixels in 'row', the pixels are
- * expanded (moved apart) in 'row' to match the final layout, when doing this
- * the pixels are *replicated* to the intervening space.  This is essential for
- * the correct operation of png_combine_row, above.
- */
-PNG_EXTERN void png_do_read_interlace PNGARG((png_row_infop row_info,
-    png_bytep row, int pass, png_uint_32 transformations));
-#endif
-
-/* GRR TO DO (2.0 or whenever):  simplify other internal calling interfaces */
-
-#ifdef PNG_WRITE_INTERLACING_SUPPORTED
-/* Grab pixels out of a row for an interlaced pass */
-PNG_EXTERN void png_do_write_interlace PNGARG((png_row_infop row_info,
-    png_bytep row, int pass));
-#endif
-
-/* Unfilter a row: check the filter value before calling this, there is no point
- * calling it for PNG_FILTER_VALUE_NONE.
- */
-PNG_EXTERN void png_read_filter_row PNGARG((png_structp pp, png_row_infop
-    row_info, png_bytep row, png_const_bytep prev_row, int filter));
-
-PNG_EXTERN void png_read_filter_row_up_neon PNGARG((png_row_infop row_info,
-    png_bytep row, png_const_bytep prev_row));
-PNG_EXTERN void png_read_filter_row_sub3_neon PNGARG((png_row_infop row_info,
-    png_bytep row, png_const_bytep prev_row));
-PNG_EXTERN void png_read_filter_row_sub4_neon PNGARG((png_row_infop row_info,
-    png_bytep row, png_const_bytep prev_row));
-PNG_EXTERN void png_read_filter_row_avg3_neon PNGARG((png_row_infop row_info,
-    png_bytep row, png_const_bytep prev_row));
-PNG_EXTERN void png_read_filter_row_avg4_neon PNGARG((png_row_infop row_info,
-    png_bytep row, png_const_bytep prev_row));
-PNG_EXTERN void png_read_filter_row_paeth3_neon PNGARG((png_row_infop row_info,
-    png_bytep row, png_const_bytep prev_row));
-PNG_EXTERN void png_read_filter_row_paeth4_neon PNGARG((png_row_infop row_info,
-    png_bytep row, png_const_bytep prev_row));
-
-/* Choose the best filter to use and filter the row data */
-PNG_EXTERN void png_write_find_filter PNGARG((png_structp png_ptr,
-    png_row_infop row_info));
-
-/* Finish a row while reading, dealing with interlacing passes, etc. */
-PNG_EXTERN void png_read_finish_row PNGARG((png_structp png_ptr));
-
-/* Initialize the row buffers, etc. */
-PNG_EXTERN void png_read_start_row PNGARG((png_structp png_ptr));
-
-#ifdef PNG_READ_TRANSFORMS_SUPPORTED
-/* Optional call to update the users info structure */
-PNG_EXTERN void png_read_transform_info PNGARG((png_structp png_ptr,
-    png_infop info_ptr));
-#endif
-
-/* These are the functions that do the transformations */
-#ifdef PNG_READ_FILLER_SUPPORTED
-PNG_EXTERN void png_do_read_filler PNGARG((png_row_infop row_info,
-    png_bytep row, png_uint_32 filler, png_uint_32 flags));
-#endif
-
-#ifdef PNG_READ_SWAP_ALPHA_SUPPORTED
-PNG_EXTERN void png_do_read_swap_alpha PNGARG((png_row_infop row_info,
-    png_bytep row));
-#endif
-
-#ifdef PNG_WRITE_SWAP_ALPHA_SUPPORTED
-PNG_EXTERN void png_do_write_swap_alpha PNGARG((png_row_infop row_info,
-    png_bytep row));
-#endif
-
-#ifdef PNG_READ_INVERT_ALPHA_SUPPORTED
-PNG_EXTERN void png_do_read_invert_alpha PNGARG((png_row_infop row_info,
-    png_bytep row));
-#endif
-
-#ifdef PNG_WRITE_INVERT_ALPHA_SUPPORTED
-PNG_EXTERN void png_do_write_invert_alpha PNGARG((png_row_infop row_info,
-    png_bytep row));
-#endif
-
-#if defined(PNG_WRITE_FILLER_SUPPORTED) || \
-    defined(PNG_READ_STRIP_ALPHA_SUPPORTED)
-PNG_EXTERN void png_do_strip_channel PNGARG((png_row_infop row_info,
-    png_bytep row, int at_start));
-#endif
-
-#ifdef PNG_16BIT_SUPPORTED
-#if defined(PNG_READ_SWAP_SUPPORTED) || defined(PNG_WRITE_SWAP_SUPPORTED)
-PNG_EXTERN void png_do_swap PNGARG((png_row_infop row_info,
-    png_bytep row));
-#endif
-#endif
-
-#if defined(PNG_READ_PACKSWAP_SUPPORTED) || \
-    defined(PNG_WRITE_PACKSWAP_SUPPORTED)
-PNG_EXTERN void png_do_packswap PNGARG((png_row_infop row_info,
-    png_bytep row));
-#endif
-
-#ifdef PNG_READ_RGB_TO_GRAY_SUPPORTED
-PNG_EXTERN int png_do_rgb_to_gray PNGARG((png_structp png_ptr,
-    png_row_infop row_info, png_bytep row));
-#endif
-
-#ifdef PNG_READ_GRAY_TO_RGB_SUPPORTED
-PNG_EXTERN void png_do_gray_to_rgb PNGARG((png_row_infop row_info,
-    png_bytep row));
-#endif
-
-#ifdef PNG_READ_PACK_SUPPORTED
-PNG_EXTERN void png_do_unpack PNGARG((png_row_infop row_info,
-    png_bytep row));
-#endif
-
-#ifdef PNG_READ_SHIFT_SUPPORTED
-PNG_EXTERN void png_do_unshift PNGARG((png_row_infop row_info,
-    png_bytep row, png_const_color_8p sig_bits));
-#endif
-
-#if defined(PNG_READ_INVERT_SUPPORTED) || defined(PNG_WRITE_INVERT_SUPPORTED)
-PNG_EXTERN void png_do_invert PNGARG((png_row_infop row_info,
-    png_bytep row));
-#endif
-
-#ifdef PNG_READ_SCALE_16_TO_8_SUPPORTED
-PNG_EXTERN void png_do_scale_16_to_8 PNGARG((png_row_infop row_info,
-    png_bytep row));
-#endif
-
-#ifdef PNG_READ_STRIP_16_TO_8_SUPPORTED
-PNG_EXTERN void png_do_chop PNGARG((png_row_infop row_info,
-    png_bytep row));
-#endif
-
-#ifdef PNG_READ_QUANTIZE_SUPPORTED
-PNG_EXTERN void png_do_quantize PNGARG((png_row_infop row_info,
-    png_bytep row, png_const_bytep palette_lookup,
-    png_const_bytep quantize_lookup));
-
-#  ifdef PNG_CORRECT_PALETTE_SUPPORTED
-PNG_EXTERN void png_correct_palette PNGARG((png_structp png_ptr,
-    png_colorp palette, int num_palette));
-#  endif
-#endif
-
-#if defined(PNG_READ_BGR_SUPPORTED) || defined(PNG_WRITE_BGR_SUPPORTED)
-PNG_EXTERN void png_do_bgr PNGARG((png_row_infop row_info,
-    png_bytep row));
-#endif
-
-#ifdef PNG_WRITE_PACK_SUPPORTED
-PNG_EXTERN void png_do_pack PNGARG((png_row_infop row_info,
-   png_bytep row, png_uint_32 bit_depth));
-#endif
-
-#ifdef PNG_WRITE_SHIFT_SUPPORTED
-PNG_EXTERN void png_do_shift PNGARG((png_row_infop row_info,
-    png_bytep row, png_const_color_8p bit_depth));
-#endif
-
-#if defined(PNG_READ_BACKGROUND_SUPPORTED) ||\
-    defined(PNG_READ_ALPHA_MODE_SUPPORTED)
-PNG_EXTERN void png_do_compose PNGARG((png_row_infop row_info,
-    png_bytep row, png_structp png_ptr));
-#endif
-
-#ifdef PNG_READ_GAMMA_SUPPORTED
-PNG_EXTERN void png_do_gamma PNGARG((png_row_infop row_info,
-    png_bytep row, png_structp png_ptr));
-#endif
-
-#ifdef PNG_READ_ALPHA_MODE_SUPPORTED
-PNG_EXTERN void png_do_encode_alpha PNGARG((png_row_infop row_info,
-   png_bytep row, png_structp png_ptr));
-#endif
-
-#ifdef PNG_READ_EXPAND_SUPPORTED
-PNG_EXTERN void png_do_expand_palette PNGARG((png_row_infop row_info,
-    png_bytep row, png_const_colorp palette, png_const_bytep trans,
-    int num_trans));
-PNG_EXTERN void png_do_expand PNGARG((png_row_infop row_info,
-    png_bytep row, png_const_color_16p trans_color));
-#endif
-
-#ifdef PNG_READ_EXPAND_16_SUPPORTED
-PNG_EXTERN void png_do_expand_16 PNGARG((png_row_infop row_info,
-    png_bytep row));
-#endif
-
-/* The following decodes the appropriate chunks, and does error correction,
- * then calls the appropriate callback for the chunk if it is valid.
- */
-
-/* Decode the IHDR chunk */
-PNG_EXTERN void png_handle_IHDR PNGARG((png_structp png_ptr, png_infop info_ptr,
-    png_uint_32 length));
-PNG_EXTERN void png_handle_PLTE PNGARG((png_structp png_ptr, png_infop info_ptr,
-    png_uint_32 length));
-PNG_EXTERN void png_handle_IEND PNGARG((png_structp png_ptr, png_infop info_ptr,
-    png_uint_32 length));
-
-#ifdef PNG_READ_bKGD_SUPPORTED
-PNG_EXTERN void png_handle_bKGD PNGARG((png_structp png_ptr, png_infop info_ptr,
-    png_uint_32 length));
-#endif
-
-#ifdef PNG_READ_cHRM_SUPPORTED
-PNG_EXTERN void png_handle_cHRM PNGARG((png_structp png_ptr, png_infop info_ptr,
-    png_uint_32 length));
-#endif
-
-#ifdef PNG_READ_gAMA_SUPPORTED
-PNG_EXTERN void png_handle_gAMA PNGARG((png_structp png_ptr, png_infop info_ptr,
-    png_uint_32 length));
-#endif
-
-#ifdef PNG_READ_hIST_SUPPORTED
-PNG_EXTERN void png_handle_hIST PNGARG((png_structp png_ptr, png_infop info_ptr,
-    png_uint_32 length));
-#endif
-
-#ifdef PNG_READ_iCCP_SUPPORTED
-PNG_EXTERN void png_handle_iCCP PNGARG((png_structp png_ptr, png_infop info_ptr,
-    png_uint_32 length));
-#endif /* PNG_READ_iCCP_SUPPORTED */
-
-#ifdef PNG_READ_iTXt_SUPPORTED
-PNG_EXTERN void png_handle_iTXt PNGARG((png_structp png_ptr, png_infop info_ptr,
-    png_uint_32 length));
-#endif
-
-#ifdef PNG_READ_oFFs_SUPPORTED
-PNG_EXTERN void png_handle_oFFs PNGARG((png_structp png_ptr, png_infop info_ptr,
-    png_uint_32 length));
-#endif
-
-#ifdef PNG_READ_pCAL_SUPPORTED
-PNG_EXTERN void png_handle_pCAL PNGARG((png_structp png_ptr, png_infop info_ptr,
-    png_uint_32 length));
-#endif
-
-#ifdef PNG_READ_pHYs_SUPPORTED
-PNG_EXTERN void png_handle_pHYs PNGARG((png_structp png_ptr, png_infop info_ptr,
-    png_uint_32 length));
-#endif
-
-#ifdef PNG_READ_sBIT_SUPPORTED
-PNG_EXTERN void png_handle_sBIT PNGARG((png_structp png_ptr, png_infop info_ptr,
-    png_uint_32 length));
-#endif
-
-#ifdef PNG_READ_sCAL_SUPPORTED
-PNG_EXTERN void png_handle_sCAL PNGARG((png_structp png_ptr, png_infop info_ptr,
-    png_uint_32 length));
-#endif
-
-#ifdef PNG_READ_sPLT_SUPPORTED
-PNG_EXTERN void png_handle_sPLT PNGARG((png_structp png_ptr, png_infop info_ptr,
-    png_uint_32 length));
-#endif /* PNG_READ_sPLT_SUPPORTED */
-
-#ifdef PNG_READ_sRGB_SUPPORTED
-PNG_EXTERN void png_handle_sRGB PNGARG((png_structp png_ptr, png_infop info_ptr,
-    png_uint_32 length));
-#endif
-
-#ifdef PNG_READ_tEXt_SUPPORTED
-PNG_EXTERN void png_handle_tEXt PNGARG((png_structp png_ptr, png_infop info_ptr,
-    png_uint_32 length));
-#endif
-
-#ifdef PNG_READ_tIME_SUPPORTED
-PNG_EXTERN void png_handle_tIME PNGARG((png_structp png_ptr, png_infop info_ptr,
-    png_uint_32 length));
-#endif
-
-#ifdef PNG_READ_tRNS_SUPPORTED
-PNG_EXTERN void png_handle_tRNS PNGARG((png_structp png_ptr, png_infop info_ptr,
-    png_uint_32 length));
-#endif
-
-#ifdef PNG_READ_zTXt_SUPPORTED
-PNG_EXTERN void png_handle_zTXt PNGARG((png_structp png_ptr, png_infop info_ptr,
-    png_uint_32 length));
-#endif
-
-PNG_EXTERN void png_handle_unknown PNGARG((png_structp png_ptr,
-    png_infop info_ptr, png_uint_32 length));
-
-PNG_EXTERN void png_check_chunk_name PNGARG((png_structp png_ptr,
-    png_uint_32 chunk_name));
-
-#ifdef PNG_HANDLE_AS_UNKNOWN_SUPPORTED
-/* Exactly as png_handle_as_unknown() except that the argument is a 32-bit chunk
- * name, not a string.
- */
-PNG_EXTERN int png_chunk_unknown_handling PNGARG((png_structp png_ptr,
-    png_uint_32 chunk_name));
-#endif
-
-/* Handle the transformations for reading and writing */
-#ifdef PNG_READ_TRANSFORMS_SUPPORTED
-PNG_EXTERN void png_do_read_transformations PNGARG((png_structp png_ptr,
-   png_row_infop row_info));
-#endif
-#ifdef PNG_WRITE_TRANSFORMS_SUPPORTED
-PNG_EXTERN void png_do_write_transformations PNGARG((png_structp png_ptr,
-   png_row_infop row_info));
-#endif
-
-#ifdef PNG_READ_TRANSFORMS_SUPPORTED
-PNG_EXTERN void png_init_read_transformations PNGARG((png_structp png_ptr));
-#endif
-
-#ifdef PNG_PROGRESSIVE_READ_SUPPORTED
-PNG_EXTERN void png_push_read_chunk PNGARG((png_structp png_ptr,
-    png_infop info_ptr));
-PNG_EXTERN void png_push_read_sig PNGARG((png_structp png_ptr,
-    png_infop info_ptr));
-PNG_EXTERN void png_push_check_crc PNGARG((png_structp png_ptr));
-PNG_EXTERN void png_push_crc_skip PNGARG((png_structp png_ptr,
-    png_uint_32 length));
-PNG_EXTERN void png_push_crc_finish PNGARG((png_structp png_ptr));
-PNG_EXTERN void png_push_save_buffer PNGARG((png_structp png_ptr));
-PNG_EXTERN void png_push_restore_buffer PNGARG((png_structp png_ptr,
-    png_bytep buffer, png_size_t buffer_length));
-PNG_EXTERN void png_push_read_IDAT PNGARG((png_structp png_ptr));
-PNG_EXTERN void png_process_IDAT_data PNGARG((png_structp png_ptr,
-    png_bytep buffer, png_size_t buffer_length));
-PNG_EXTERN void png_push_process_row PNGARG((png_structp png_ptr));
-PNG_EXTERN void png_push_handle_unknown PNGARG((png_structp png_ptr,
-   png_infop info_ptr, png_uint_32 length));
-PNG_EXTERN void png_push_have_info PNGARG((png_structp png_ptr,
-   png_infop info_ptr));
-PNG_EXTERN void png_push_have_end PNGARG((png_structp png_ptr,
-   png_infop info_ptr));
-PNG_EXTERN void png_push_have_row PNGARG((png_structp png_ptr, png_bytep row));
-PNG_EXTERN void png_push_read_end PNGARG((png_structp png_ptr,
-    png_infop info_ptr));
-PNG_EXTERN void png_process_some_data PNGARG((png_structp png_ptr,
-    png_infop info_ptr));
-PNG_EXTERN void png_read_push_finish_row PNGARG((png_structp png_ptr));
-#  ifdef PNG_READ_tEXt_SUPPORTED
-PNG_EXTERN void png_push_handle_tEXt PNGARG((png_structp png_ptr,
-    png_infop info_ptr, png_uint_32 length));
-PNG_EXTERN void png_push_read_tEXt PNGARG((png_structp png_ptr,
-    png_infop info_ptr));
-#  endif
-#  ifdef PNG_READ_zTXt_SUPPORTED
-PNG_EXTERN void png_push_handle_zTXt PNGARG((png_structp png_ptr,
-    png_infop info_ptr, png_uint_32 length));
-PNG_EXTERN void png_push_read_zTXt PNGARG((png_structp png_ptr,
-    png_infop info_ptr));
-#  endif
-#  ifdef PNG_READ_iTXt_SUPPORTED
-PNG_EXTERN void png_push_handle_iTXt PNGARG((png_structp png_ptr,
-    png_infop info_ptr, png_uint_32 length));
-PNG_EXTERN void png_push_read_iTXt PNGARG((png_structp png_ptr,
-    png_infop info_ptr));
-#  endif
-
-#endif /* PNG_PROGRESSIVE_READ_SUPPORTED */
-
-#ifdef PNG_MNG_FEATURES_SUPPORTED
-PNG_EXTERN void png_do_read_intrapixel PNGARG((png_row_infop row_info,
-    png_bytep row));
-PNG_EXTERN void png_do_write_intrapixel PNGARG((png_row_infop row_info,
-    png_bytep row));
-#endif
-
-/* Added at libpng version 1.4.0 */
-#ifdef PNG_CHECK_cHRM_SUPPORTED
-PNG_EXTERN int png_check_cHRM_fixed PNGARG((png_structp png_ptr,
-    png_fixed_point int_white_x, png_fixed_point int_white_y,
-    png_fixed_point int_red_x, png_fixed_point int_red_y, png_fixed_point
-    int_green_x, png_fixed_point int_green_y, png_fixed_point int_blue_x,
-    png_fixed_point int_blue_y));
-#endif
-
-#ifdef PNG_CHECK_cHRM_SUPPORTED
-/* Added at libpng version 1.2.34 and 1.4.0 */
-/* Currently only used by png_check_cHRM_fixed */
-PNG_EXTERN void png_64bit_product PNGARG((long v1, long v2,
-    unsigned long *hi_product, unsigned long *lo_product));
-#endif
-
-#ifdef PNG_cHRM_SUPPORTED
-/* Added at libpng version 1.5.5 */
-typedef struct png_xy
-{
-   png_fixed_point redx, redy;
-   png_fixed_point greenx, greeny;
-   png_fixed_point bluex, bluey;
-   png_fixed_point whitex, whitey;
-} png_xy;
-
-typedef struct png_XYZ
-{
-   png_fixed_point redX, redY, redZ;
-   png_fixed_point greenX, greenY, greenZ;
-   png_fixed_point blueX, blueY, blueZ;
-} png_XYZ;
-
-/* The conversion APIs return 0 on success, non-zero on a parameter error. They
- * allow conversion between the above representations of a color encoding.  When
- * converting from XYZ end points to chromaticities the absolute magnitude of
- * the end points is lost, when converting back the sum of the Y values of the
- * three end points will be 1.0
- */
-PNG_EXTERN int png_xy_from_XYZ PNGARG((png_xy *xy, png_XYZ XYZ));
-PNG_EXTERN int png_XYZ_from_xy PNGARG((png_XYZ *XYZ, png_xy xy));
-PNG_EXTERN int png_XYZ_from_xy_checked PNGARG((png_structp png_ptr,
-   png_XYZ *XYZ, png_xy xy));
-#endif
-
-/* Added at libpng version 1.4.0 */
-PNG_EXTERN void png_check_IHDR PNGARG((png_structp png_ptr,
-    png_uint_32 width, png_uint_32 height, int bit_depth,
-    int color_type, int interlace_type, int compression_type,
-    int filter_type));
-
-/* Added at libpng version 1.5.10 */
-#if defined(PNG_READ_CHECK_FOR_INVALID_INDEX_SUPPORTED) || \
-    defined(PNG_WRITE_CHECK_FOR_INVALID_INDEX_SUPPORTED)
-PNG_EXTERN void png_do_check_palette_indexes PNGARG((png_structp png_ptr,
-    png_row_infop row_info));
-#endif
-
-/* Free all memory used by the read (old method - NOT DLL EXPORTED) */
-PNG_EXTERN void png_read_destroy PNGARG((png_structp png_ptr,
-    png_infop info_ptr, png_infop end_info_ptr));
-
-/* Free any memory used in png_ptr struct (old method - NOT DLL EXPORTED) */
-PNG_EXTERN void png_write_destroy PNGARG((png_structp png_ptr));
-
-#ifdef USE_FAR_KEYWORD  /* memory model conversion function */
-PNG_EXTERN void *png_far_to_near PNGARG((png_structp png_ptr, png_voidp ptr,
-    int check));
-#endif /* USE_FAR_KEYWORD */
-
-#if defined(PNG_FLOATING_POINT_SUPPORTED) && defined(PNG_ERROR_TEXT_SUPPORTED)
-PNG_EXTERN PNG_FUNCTION(void, png_fixed_error, (png_structp png_ptr,
-   png_const_charp name),PNG_NORETURN);
-#endif
-
-/* Puts 'string' into 'buffer' at buffer[pos], taking care never to overwrite
- * the end.  Always leaves the buffer nul terminated.  Never errors out (and
- * there is no error code.)
- */
-PNG_EXTERN size_t png_safecat(png_charp buffer, size_t bufsize, size_t pos,
-    png_const_charp string);
-
-/* Various internal functions to handle formatted warning messages, currently
- * only implemented for warnings.
- */
-#if defined(PNG_WARNINGS_SUPPORTED) || defined(PNG_TIME_RFC1123_SUPPORTED)
-/* Utility to dump an unsigned value into a buffer, given a start pointer and
- * and end pointer (which should point just *beyond* the end of the buffer!)
- * Returns the pointer to the start of the formatted string.  This utility only
- * does unsigned values.
- */
-PNG_EXTERN png_charp png_format_number(png_const_charp start, png_charp end,
-   int format, png_alloc_size_t number);
-
-/* Convenience macro that takes an array: */
-#define PNG_FORMAT_NUMBER(buffer,format,number) \
-   png_format_number(buffer, buffer + (sizeof buffer), format, number)
-
-/* Suggested size for a number buffer (enough for 64 bits and a sign!) */
-#define PNG_NUMBER_BUFFER_SIZE 24
-
-/* These are the integer formats currently supported, the name is formed from
- * the standard printf(3) format string.
- */
-#define PNG_NUMBER_FORMAT_u     1 /* chose unsigned API! */
-#define PNG_NUMBER_FORMAT_02u   2
-#define PNG_NUMBER_FORMAT_d     1 /* chose signed API! */
-#define PNG_NUMBER_FORMAT_02d   2
-#define PNG_NUMBER_FORMAT_x     3
-#define PNG_NUMBER_FORMAT_02x   4
-#define PNG_NUMBER_FORMAT_fixed 5 /* choose the signed API */
-#endif
-
-#ifdef PNG_WARNINGS_SUPPORTED
-/* New defines and members adding in libpng-1.5.4 */
-#  define PNG_WARNING_PARAMETER_SIZE 32
-#  define PNG_WARNING_PARAMETER_COUNT 8
-
-/* An l-value of this type has to be passed to the APIs below to cache the
- * values of the parameters to a formatted warning message.
- */
-typedef char png_warning_parameters[PNG_WARNING_PARAMETER_COUNT][
-   PNG_WARNING_PARAMETER_SIZE];
-
-PNG_EXTERN void png_warning_parameter(png_warning_parameters p, int number,
-    png_const_charp string);
-    /* Parameters are limited in size to PNG_WARNING_PARAMETER_SIZE characters,
-     * including the trailing '\0'.
-     */
-PNG_EXTERN void png_warning_parameter_unsigned(png_warning_parameters p,
-    int number, int format, png_alloc_size_t value);
-    /* Use png_alloc_size_t because it is an unsigned type as big as any we
-     * need to output.  Use the following for a signed value.
-     */
-PNG_EXTERN void png_warning_parameter_signed(png_warning_parameters p,
-    int number, int format, png_int_32 value);
-
-PNG_EXTERN void png_formatted_warning(png_structp png_ptr,
-    png_warning_parameters p, png_const_charp message);
-    /* 'message' follows the X/Open approach of using @1, @2 to insert
-     * parameters previously supplied using the above functions.  Errors in
-     * specifying the paramters will simple result in garbage substitutions.
-     */
-#endif
-
-/* ASCII to FP interfaces, currently only implemented if sCAL
- * support is required.
- */
-#if defined(PNG_READ_sCAL_SUPPORTED)
-/* MAX_DIGITS is actually the maximum number of characters in an sCAL
- * width or height, derived from the precision (number of significant
- * digits - a build time settable option) and assumpitions about the
- * maximum ridiculous exponent.
- */
-#define PNG_sCAL_MAX_DIGITS (PNG_sCAL_PRECISION+1/*.*/+1/*E*/+10/*exponent*/)
-
-#ifdef PNG_FLOATING_POINT_SUPPORTED
-PNG_EXTERN void png_ascii_from_fp PNGARG((png_structp png_ptr, png_charp ascii,
-    png_size_t size, double fp, unsigned int precision));
-#endif /* FLOATING_POINT */
-
-#ifdef PNG_FIXED_POINT_SUPPORTED
-PNG_EXTERN void png_ascii_from_fixed PNGARG((png_structp png_ptr,
-    png_charp ascii, png_size_t size, png_fixed_point fp));
-#endif /* FIXED_POINT */
-#endif /* READ_sCAL */
-
-#if defined(PNG_sCAL_SUPPORTED) || defined(PNG_pCAL_SUPPORTED)
-/* An internal API to validate the format of a floating point number.
- * The result is the index of the next character.  If the number is
- * not valid it will be the index of a character in the supposed number.
- *
- * The format of a number is defined in the PNG extensions specification
- * and this API is strictly conformant to that spec, not anyone elses!
- *
- * The format as a regular expression is:
- *
- * [+-]?[0-9]+.?([Ee][+-]?[0-9]+)?
- *
- * or:
- *
- * [+-]?.[0-9]+(.[0-9]+)?([Ee][+-]?[0-9]+)?
- *
- * The complexity is that either integer or fraction must be present and the
- * fraction is permitted to have no digits only if the integer is present.
- *
- * NOTE: The dangling E problem.
- *   There is a PNG valid floating point number in the following:
- *
- *       PNG floating point numb1.ers are not greedy.
- *
- *   Working this out requires *TWO* character lookahead (because of the
- *   sign), the parser does not do this - it will fail at the 'r' - this
- *   doesn't matter for PNG sCAL chunk values, but it requires more care
- *   if the value were ever to be embedded in something more complex.  Use
- *   ANSI-C strtod if you need the lookahead.
- */
-/* State table for the parser. */
-#define PNG_FP_INTEGER    0  /* before or in integer */
-#define PNG_FP_FRACTION   1  /* before or in fraction */
-#define PNG_FP_EXPONENT   2  /* before or in exponent */
-#define PNG_FP_STATE      3  /* mask for the above */
-#define PNG_FP_SAW_SIGN   4  /* Saw +/- in current state */
-#define PNG_FP_SAW_DIGIT  8  /* Saw a digit in current state */
-#define PNG_FP_SAW_DOT   16  /* Saw a dot in current state */
-#define PNG_FP_SAW_E     32  /* Saw an E (or e) in current state */
-#define PNG_FP_SAW_ANY   60  /* Saw any of the above 4 */
-
-/* These three values don't affect the parser.  They are set but not used.
- */
-#define PNG_FP_WAS_VALID 64  /* Preceding substring is a valid fp number */
-#define PNG_FP_NEGATIVE 128  /* A negative number, including "-0" */
-#define PNG_FP_NONZERO  256  /* A non-zero value */
-#define PNG_FP_STICKY   448  /* The above three flags */
-
-/* This is available for the caller to store in 'state' if required.  Do not
- * call the parser after setting it (the parser sometimes clears it.)
- */
-#define PNG_FP_INVALID  512  /* Available for callers as a distinct value */
-
-/* Result codes for the parser (boolean - true meants ok, false means
- * not ok yet.)
- */
-#define PNG_FP_MAYBE      0  /* The number may be valid in the future */
-#define PNG_FP_OK         1  /* The number is valid */
-
-/* Tests on the sticky non-zero and negative flags.  To pass these checks
- * the state must also indicate that the whole number is valid - this is
- * achieved by testing PNG_FP_SAW_DIGIT (see the implementation for why this
- * is equivalent to PNG_FP_OK above.)
- */
-#define PNG_FP_NZ_MASK (PNG_FP_SAW_DIGIT | PNG_FP_NEGATIVE | PNG_FP_NONZERO)
-   /* NZ_MASK: the string is valid and a non-zero negative value */
-#define PNG_FP_Z_MASK (PNG_FP_SAW_DIGIT | PNG_FP_NONZERO)
-   /* Z MASK: the string is valid and a non-zero value. */
-   /* PNG_FP_SAW_DIGIT: the string is valid. */
-#define PNG_FP_IS_ZERO(state) (((state) & PNG_FP_Z_MASK) == PNG_FP_SAW_DIGIT)
-#define PNG_FP_IS_POSITIVE(state) (((state) & PNG_FP_NZ_MASK) == PNG_FP_Z_MASK)
-#define PNG_FP_IS_NEGATIVE(state) (((state) & PNG_FP_NZ_MASK) == PNG_FP_NZ_MASK)
-
-/* The actual parser.  This can be called repeatedly, it updates
- * the index into the string and the state variable (which must
- * be initialzed to 0).  It returns a result code, as above.  There
- * is no point calling the parser any more if it fails to advance to
- * the end of the string - it is stuck on an invalid character (or
- * terminated by '\0').
- *
- * Note that the pointer will consume an E or even an E+ then leave
- * a 'maybe' state even though a preceding integer.fraction is valid.
- * The PNG_FP_WAS_VALID flag indicates that a preceding substring was
- * a valid number.  It's possible to recover from this by calling
- * the parser again (from the start, with state 0) but with a string
- * that omits the last character (i.e. set the size to the index of
- * the problem character.)  This has not been tested within libpng.
- */
-PNG_EXTERN int png_check_fp_number PNGARG((png_const_charp string,
-    png_size_t size, int *statep, png_size_tp whereami));
-
-/* This is the same but it checks a complete string and returns true
- * only if it just contains a floating point number.  As of 1.5.4 this
- * function also returns the state at the end of parsing the number if
- * it was valid (otherwise it returns 0.)  This can be used for testing
- * for negative or zero values using the sticky flag.
- */
-PNG_EXTERN int png_check_fp_string PNGARG((png_const_charp string,
-    png_size_t size));
-#endif /* pCAL || sCAL */
-
-#if defined(PNG_READ_GAMMA_SUPPORTED) ||\
-    defined(PNG_INCH_CONVERSIONS_SUPPORTED) || defined(PNG_READ_pHYs_SUPPORTED)
-/* Added at libpng version 1.5.0 */
-/* This is a utility to provide a*times/div (rounded) and indicate
- * if there is an overflow.  The result is a boolean - false (0)
- * for overflow, true (1) if no overflow, in which case *res
- * holds the result.
- */
-PNG_EXTERN int png_muldiv PNGARG((png_fixed_point_p res, png_fixed_point a,
-    png_int_32 multiplied_by, png_int_32 divided_by));
-#endif
-
-#if defined(PNG_READ_GAMMA_SUPPORTED) || defined(PNG_INCH_CONVERSIONS_SUPPORTED)
-/* Same deal, but issue a warning on overflow and return 0. */
-PNG_EXTERN png_fixed_point png_muldiv_warn PNGARG((png_structp png_ptr,
-    png_fixed_point a, png_int_32 multiplied_by, png_int_32 divided_by));
-#endif
-
-#ifdef PNG_READ_GAMMA_SUPPORTED
-/* Calculate a reciprocal - used for gamma values.  This returns
- * 0 if the argument is 0 in order to maintain an undefined value,
- * there are no warnings.
- */
-PNG_EXTERN png_fixed_point png_reciprocal PNGARG((png_fixed_point a));
-
-/* The same but gives a reciprocal of the product of two fixed point
- * values.  Accuracy is suitable for gamma calculations but this is
- * not exact - use png_muldiv for that.
- */
-PNG_EXTERN png_fixed_point png_reciprocal2 PNGARG((png_fixed_point a,
-    png_fixed_point b));
-#endif
-
-#ifdef PNG_READ_GAMMA_SUPPORTED
-/* Internal fixed point gamma correction.  These APIs are called as
- * required to convert single values - they don't need to be fast,
- * they are not used when processing image pixel values.
- *
- * While the input is an 'unsigned' value it must actually be the
- * correct bit value - 0..255 or 0..65535 as required.
- */
-PNG_EXTERN png_uint_16 png_gamma_correct PNGARG((png_structp png_ptr,
-    unsigned int value, png_fixed_point gamma_value));
-PNG_EXTERN int png_gamma_significant PNGARG((png_fixed_point gamma_value));
-PNG_EXTERN png_uint_16 png_gamma_16bit_correct PNGARG((unsigned int value,
-    png_fixed_point gamma_value));
-PNG_EXTERN png_byte png_gamma_8bit_correct PNGARG((unsigned int value,
-    png_fixed_point gamma_value));
-PNG_EXTERN void png_destroy_gamma_table(png_structp png_ptr);
-PNG_EXTERN void png_build_gamma_table PNGARG((png_structp png_ptr,
-    int bit_depth));
-#endif
-
-/* Maintainer: Put new private prototypes here ^ and in libpngpf.3 */
-
-#include "pngdebug.h"
-
-#ifdef __cplusplus
-}
-#endif
-
-#endif /* PNGPRIV_H */
diff --git a/plugingui/png/pngread.c b/plugingui/png/pngread.c
deleted file mode 100644
index ecb138d..0000000
--- a/plugingui/png/pngread.c
+++ /dev/null
@@ -1,1305 +0,0 @@
-
-/* pngread.c - read a PNG file
- *
- * Last changed in libpng 1.5.10 [March 8, 2012]
- * Copyright (c) 1998-2012 Glenn Randers-Pehrson
- * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
- * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)
- *
- * This code is released under the libpng license.
- * For conditions of distribution and use, see the disclaimer
- * and license in png.h
- *
- * This file contains routines that an application calls directly to
- * read a PNG file or stream.
- */
-
-#include "pngpriv.h"
-
-#ifdef PNG_READ_SUPPORTED
-
-/* Create a PNG structure for reading, and allocate any memory needed. */
-PNG_FUNCTION(png_structp,PNGAPI
-dg_png_create_read_struct,(png_const_charp user_png_ver, png_voidp error_ptr,
-    png_error_ptr error_fn, png_error_ptr warn_fn),PNG_ALLOCATED)
-{
-
-#ifdef PNG_USER_MEM_SUPPORTED
-   return (png_create_read_struct_2(user_png_ver, error_ptr, error_fn,
-       warn_fn, NULL, NULL, NULL));
-}
-
-/* Alternate create PNG structure for reading, and allocate any memory
- * needed.
- */
-PNG_FUNCTION(png_structp,PNGAPI
-png_create_read_struct_2,(png_const_charp user_png_ver, png_voidp error_ptr,
-    png_error_ptr error_fn, png_error_ptr warn_fn, png_voidp mem_ptr,
-    png_malloc_ptr malloc_fn, png_free_ptr free_fn),PNG_ALLOCATED)
-{
-#endif /* PNG_USER_MEM_SUPPORTED */
-
-#ifdef PNG_SETJMP_SUPPORTED
-   volatile
-#endif
-   png_structp png_ptr;
-   volatile int png_cleanup_needed = 0;
-
-#ifdef PNG_SETJMP_SUPPORTED
-#ifdef USE_FAR_KEYWORD
-   jmp_buf tmp_jmpbuf;
-#endif
-#endif
-
-   png_debug(1, "in png_create_read_struct");
-
-#ifdef PNG_USER_MEM_SUPPORTED
-   png_ptr = (png_structp)png_create_struct_2(PNG_STRUCT_PNG,
-       malloc_fn, mem_ptr);
-#else
-   png_ptr = (png_structp)png_create_struct(PNG_STRUCT_PNG);
-#endif
-   if (png_ptr == NULL)
-      return (NULL);
-
-   /* Added at libpng-1.2.6 */
-#ifdef PNG_USER_LIMITS_SUPPORTED
-   png_ptr->user_width_max = PNG_USER_WIDTH_MAX;
-   png_ptr->user_height_max = PNG_USER_HEIGHT_MAX;
-
-   /* Added at libpng-1.2.43 and 1.4.0 */
-   png_ptr->user_chunk_cache_max = PNG_USER_CHUNK_CACHE_MAX;
-
-   /* Added at libpng-1.2.43 and 1.4.1 */
-   png_ptr->user_chunk_malloc_max = PNG_USER_CHUNK_MALLOC_MAX;
-#endif
-
-#ifdef PNG_SETJMP_SUPPORTED
-/* Applications that neglect to set up their own setjmp() and then
- * encounter a png_error() will longjmp here.  Since the jmpbuf is
- * then meaningless we abort instead of returning.
- */
-#ifdef USE_FAR_KEYWORD
-   if (setjmp(tmp_jmpbuf))
-#else
-   if (setjmp(dg_png_jmpbuf(png_ptr))) /* Sets longjmp to match setjmp */
-#endif
-      PNG_ABORT();
-#ifdef USE_FAR_KEYWORD
-   png_memcpy(png_jmpbuf(png_ptr), tmp_jmpbuf, png_sizeof(jmp_buf));
-#endif
-#endif /* PNG_SETJMP_SUPPORTED */
-
-#ifdef PNG_USER_MEM_SUPPORTED
-   png_set_mem_fn(png_ptr, mem_ptr, malloc_fn, free_fn);
-#endif
-
-   png_set_error_fn(png_ptr, error_ptr, error_fn, warn_fn);
-
-   /* Call the general version checker (shared with read and write code): */
-   if (!png_user_version_check(png_ptr, user_png_ver))
-      png_cleanup_needed = 1;
-
-   if (!png_cleanup_needed)
-   {
-   /* Initialize zbuf - compression buffer */
-   png_ptr->zbuf_size = PNG_ZBUF_SIZE;
-   png_ptr->zbuf = (png_bytep)png_malloc_warn(png_ptr, png_ptr->zbuf_size);
-
-   if (png_ptr->zbuf == NULL)
-      png_cleanup_needed = 1;
-   }
-
-   png_ptr->zstream.zalloc = png_zalloc;
-   png_ptr->zstream.zfree = png_zfree;
-   png_ptr->zstream.opaque = (voidpf)png_ptr;
-
-   if (!png_cleanup_needed)
-   {
-      switch (inflateInit(&png_ptr->zstream))
-      {
-         case Z_OK:
-            break; /* Do nothing */
-
-         case Z_MEM_ERROR:
-            png_warning(png_ptr, "zlib memory error");
-            png_cleanup_needed = 1;
-            break;
-
-         case Z_STREAM_ERROR:
-            png_warning(png_ptr, "zlib stream error");
-            png_cleanup_needed = 1;
-            break;
-
-         case Z_VERSION_ERROR:
-            png_warning(png_ptr, "zlib version error");
-            png_cleanup_needed = 1;
-            break;
-
-         default: png_warning(png_ptr, "Unknown zlib error");
-            png_cleanup_needed = 1;
-      }
-   }
-
-   if (png_cleanup_needed)
-   {
-      /* Clean up PNG structure and deallocate any memory. */
-      png_free(png_ptr, png_ptr->zbuf);
-      png_ptr->zbuf = NULL;
-#ifdef PNG_USER_MEM_SUPPORTED
-      png_destroy_struct_2((png_voidp)png_ptr,
-          (png_free_ptr)free_fn, (png_voidp)mem_ptr);
-#else
-      png_destroy_struct((png_voidp)png_ptr);
-#endif
-      return (NULL);
-   }
-
-   png_ptr->zstream.next_out = png_ptr->zbuf;
-   png_ptr->zstream.avail_out = (uInt)png_ptr->zbuf_size;
-
-   dg_png_set_read_fn(png_ptr, NULL, NULL);
-
-
-   return (png_ptr);
-}
-
-
-#ifdef PNG_SEQUENTIAL_READ_SUPPORTED
-/* Read the information before the actual image data.  This has been
- * changed in v0.90 to allow reading a file that already has the magic
- * bytes read from the stream.  You can tell libpng how many bytes have
- * been read from the beginning of the stream (up to the maximum of 8)
- * via png_set_sig_bytes(), and we will only check the remaining bytes
- * here.  The application can then have access to the signature bytes we
- * read if it is determined that this isn't a valid PNG file.
- */
-void PNGAPI
-dg_png_read_info(png_structp png_ptr, png_infop info_ptr)
-{
-   png_debug(1, "in png_read_info");
-
-   if (png_ptr == NULL || info_ptr == NULL)
-      return;
-
-   /* Read and check the PNG file signature. */
-   png_read_sig(png_ptr, info_ptr);
-
-   for (;;)
-   {
-      png_uint_32 length = png_read_chunk_header(png_ptr);
-      png_uint_32 chunk_name = png_ptr->chunk_name;
-
-      /* This should be a binary subdivision search or a hash for
-       * matching the chunk name rather than a linear search.
-       */
-      if (chunk_name == png_IDAT)
-         if (png_ptr->mode & PNG_AFTER_IDAT)
-            png_ptr->mode |= PNG_HAVE_CHUNK_AFTER_IDAT;
-
-      if (chunk_name == png_IHDR)
-         png_handle_IHDR(png_ptr, info_ptr, length);
-
-      else if (chunk_name == png_IEND)
-         png_handle_IEND(png_ptr, info_ptr, length);
-
-#ifdef PNG_HANDLE_AS_UNKNOWN_SUPPORTED
-      else if (png_chunk_unknown_handling(png_ptr, chunk_name) !=
-         PNG_HANDLE_CHUNK_AS_DEFAULT)
-      {
-         if (chunk_name == png_IDAT)
-            png_ptr->mode |= PNG_HAVE_IDAT;
-
-         png_handle_unknown(png_ptr, info_ptr, length);
-
-         if (chunk_name == png_PLTE)
-            png_ptr->mode |= PNG_HAVE_PLTE;
-
-         else if (chunk_name == png_IDAT)
-         {
-            if (!(png_ptr->mode & PNG_HAVE_IHDR))
-               dg_png_error(png_ptr, "Missing IHDR before IDAT");
-
-            else if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE &&
-                !(png_ptr->mode & PNG_HAVE_PLTE))
-               dg_png_error(png_ptr, "Missing PLTE before IDAT");
-
-            break;
-         }
-      }
-#endif
-      else if (chunk_name == png_PLTE)
-         png_handle_PLTE(png_ptr, info_ptr, length);
-
-      else if (chunk_name == png_IDAT)
-      {
-         if (!(png_ptr->mode & PNG_HAVE_IHDR))
-            dg_png_error(png_ptr, "Missing IHDR before IDAT");
-
-         else if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE &&
-             !(png_ptr->mode & PNG_HAVE_PLTE))
-            dg_png_error(png_ptr, "Missing PLTE before IDAT");
-
-         png_ptr->idat_size = length;
-         png_ptr->mode |= PNG_HAVE_IDAT;
-         break;
-      }
-
-#ifdef PNG_READ_bKGD_SUPPORTED
-      else if (chunk_name == png_bKGD)
-         png_handle_bKGD(png_ptr, info_ptr, length);
-#endif
-
-#ifdef PNG_READ_cHRM_SUPPORTED
-      else if (chunk_name == png_cHRM)
-         png_handle_cHRM(png_ptr, info_ptr, length);
-#endif
-
-#ifdef PNG_READ_gAMA_SUPPORTED
-      else if (chunk_name == png_gAMA)
-         png_handle_gAMA(png_ptr, info_ptr, length);
-#endif
-
-#ifdef PNG_READ_hIST_SUPPORTED
-      else if (chunk_name == png_hIST)
-         png_handle_hIST(png_ptr, info_ptr, length);
-#endif
-
-#ifdef PNG_READ_oFFs_SUPPORTED
-      else if (chunk_name == png_oFFs)
-         png_handle_oFFs(png_ptr, info_ptr, length);
-#endif
-
-#ifdef PNG_READ_pCAL_SUPPORTED
-      else if (chunk_name == png_pCAL)
-         png_handle_pCAL(png_ptr, info_ptr, length);
-#endif
-
-#ifdef PNG_READ_sCAL_SUPPORTED
-      else if (chunk_name == png_sCAL)
-         png_handle_sCAL(png_ptr, info_ptr, length);
-#endif
-
-#ifdef PNG_READ_pHYs_SUPPORTED
-      else if (chunk_name == png_pHYs)
-         png_handle_pHYs(png_ptr, info_ptr, length);
-#endif
-
-#ifdef PNG_READ_sBIT_SUPPORTED
-      else if (chunk_name == png_sBIT)
-         png_handle_sBIT(png_ptr, info_ptr, length);
-#endif
-
-#ifdef PNG_READ_sRGB_SUPPORTED
-      else if (chunk_name == png_sRGB)
-         png_handle_sRGB(png_ptr, info_ptr, length);
-#endif
-
-#ifdef PNG_READ_iCCP_SUPPORTED
-      else if (chunk_name == png_iCCP)
-         png_handle_iCCP(png_ptr, info_ptr, length);
-#endif
-
-#ifdef PNG_READ_sPLT_SUPPORTED
-      else if (chunk_name == png_sPLT)
-         png_handle_sPLT(png_ptr, info_ptr, length);
-#endif
-
-#ifdef PNG_READ_tEXt_SUPPORTED
-      else if (chunk_name == png_tEXt)
-         png_handle_tEXt(png_ptr, info_ptr, length);
-#endif
-
-#ifdef PNG_READ_tIME_SUPPORTED
-      else if (chunk_name == png_tIME)
-         png_handle_tIME(png_ptr, info_ptr, length);
-#endif
-
-#ifdef PNG_READ_tRNS_SUPPORTED
-      else if (chunk_name == png_tRNS)
-         png_handle_tRNS(png_ptr, info_ptr, length);
-#endif
-
-#ifdef PNG_READ_zTXt_SUPPORTED
-      else if (chunk_name == png_zTXt)
-         png_handle_zTXt(png_ptr, info_ptr, length);
-#endif
-
-#ifdef PNG_READ_iTXt_SUPPORTED
-      else if (chunk_name == png_iTXt)
-         png_handle_iTXt(png_ptr, info_ptr, length);
-#endif
-
-      else
-         png_handle_unknown(png_ptr, info_ptr, length);
-   }
-}
-#endif /* PNG_SEQUENTIAL_READ_SUPPORTED */
-
-/* Optional call to update the users info_ptr structure */
-void PNGAPI
-dg_png_read_update_info(png_structp png_ptr, png_infop info_ptr)
-{
-   png_debug(1, "in png_read_update_info");
-
-   if (png_ptr == NULL)
-      return;
-
-   png_read_start_row(png_ptr);
-
-#ifdef PNG_READ_TRANSFORMS_SUPPORTED
-   png_read_transform_info(png_ptr, info_ptr);
-#else
-   PNG_UNUSED(info_ptr)
-#endif
-}
-
-#ifdef PNG_SEQUENTIAL_READ_SUPPORTED
-/* Initialize palette, background, etc, after transformations
- * are set, but before any reading takes place.  This allows
- * the user to obtain a gamma-corrected palette, for example.
- * If the user doesn't call this, we will do it ourselves.
- */
-void PNGAPI
-png_start_read_image(png_structp png_ptr)
-{
-   png_debug(1, "in png_start_read_image");
-
-   if (png_ptr != NULL)
-     png_read_start_row(png_ptr);
-}
-#endif /* PNG_SEQUENTIAL_READ_SUPPORTED */
-
-#ifdef PNG_SEQUENTIAL_READ_SUPPORTED
-void PNGAPI
-png_read_row(png_structp png_ptr, png_bytep row, png_bytep dsp_row)
-{
-   int ret;
-
-   png_row_info row_info;
-
-   if (png_ptr == NULL)
-      return;
-
-   png_debug2(1, "in png_read_row (row %lu, pass %d)",
-       (unsigned long)png_ptr->row_number, png_ptr->pass);
-
-   /* png_read_start_row sets the information (in particular iwidth) for this
-    * interlace pass.
-    */
-   if (!(png_ptr->flags & PNG_FLAG_ROW_INIT))
-      png_read_start_row(png_ptr);
-
-   /* 1.5.6: row_info moved out of png_struct to a local here. */
-   row_info.width = png_ptr->iwidth; /* NOTE: width of current interlaced row */
-   row_info.color_type = png_ptr->color_type;
-   row_info.bit_depth = png_ptr->bit_depth;
-   row_info.channels = png_ptr->channels;
-   row_info.pixel_depth = png_ptr->pixel_depth;
-   row_info.rowbytes = PNG_ROWBYTES(row_info.pixel_depth, row_info.width);
-
-   if (png_ptr->row_number == 0 && png_ptr->pass == 0)
-   {
-   /* Check for transforms that have been set but were defined out */
-#if defined(PNG_WRITE_INVERT_SUPPORTED) && !defined(PNG_READ_INVERT_SUPPORTED)
-   if (png_ptr->transformations & PNG_INVERT_MONO)
-      png_warning(png_ptr, "PNG_READ_INVERT_SUPPORTED is not defined");
-#endif
-
-#if defined(PNG_WRITE_FILLER_SUPPORTED) && !defined(PNG_READ_FILLER_SUPPORTED)
-   if (png_ptr->transformations & PNG_FILLER)
-      png_warning(png_ptr, "PNG_READ_FILLER_SUPPORTED is not defined");
-#endif
-
-#if defined(PNG_WRITE_PACKSWAP_SUPPORTED) && \
-    !defined(PNG_READ_PACKSWAP_SUPPORTED)
-   if (png_ptr->transformations & PNG_PACKSWAP)
-      png_warning(png_ptr, "PNG_READ_PACKSWAP_SUPPORTED is not defined");
-#endif
-
-#if defined(PNG_WRITE_PACK_SUPPORTED) && !defined(PNG_READ_PACK_SUPPORTED)
-   if (png_ptr->transformations & PNG_PACK)
-      png_warning(png_ptr, "PNG_READ_PACK_SUPPORTED is not defined");
-#endif
-
-#if defined(PNG_WRITE_SHIFT_SUPPORTED) && !defined(PNG_READ_SHIFT_SUPPORTED)
-   if (png_ptr->transformations & PNG_SHIFT)
-      png_warning(png_ptr, "PNG_READ_SHIFT_SUPPORTED is not defined");
-#endif
-
-#if defined(PNG_WRITE_BGR_SUPPORTED) && !defined(PNG_READ_BGR_SUPPORTED)
-   if (png_ptr->transformations & PNG_BGR)
-      png_warning(png_ptr, "PNG_READ_BGR_SUPPORTED is not defined");
-#endif
-
-#if defined(PNG_WRITE_SWAP_SUPPORTED) && !defined(PNG_READ_SWAP_SUPPORTED)
-   if (png_ptr->transformations & PNG_SWAP_BYTES)
-      png_warning(png_ptr, "PNG_READ_SWAP_SUPPORTED is not defined");
-#endif
-   }
-
-#ifdef PNG_READ_INTERLACING_SUPPORTED
-   /* If interlaced and we do not need a new row, combine row and return.
-    * Notice that the pixels we have from previous rows have been transformed
-    * already; we can only combine like with like (transformed or
-    * untransformed) and, because of the libpng API for interlaced images, this
-    * means we must transform before de-interlacing.
-    */
-   if (png_ptr->interlaced && (png_ptr->transformations & PNG_INTERLACE))
-   {
-      switch (png_ptr->pass)
-      {
-         case 0:
-            if (png_ptr->row_number & 0x07)
-            {
-               if (dsp_row != NULL)
-                  png_combine_row(png_ptr, dsp_row, 1/*display*/);
-               png_read_finish_row(png_ptr);
-               return;
-            }
-            break;
-
-         case 1:
-            if ((png_ptr->row_number & 0x07) || png_ptr->width < 5)
-            {
-               if (dsp_row != NULL)
-                  png_combine_row(png_ptr, dsp_row, 1/*display*/);
-
-               png_read_finish_row(png_ptr);
-               return;
-            }
-            break;
-
-         case 2:
-            if ((png_ptr->row_number & 0x07) != 4)
-            {
-               if (dsp_row != NULL && (png_ptr->row_number & 4))
-                  png_combine_row(png_ptr, dsp_row, 1/*display*/);
-
-               png_read_finish_row(png_ptr);
-               return;
-            }
-            break;
-
-         case 3:
-            if ((png_ptr->row_number & 3) || png_ptr->width < 3)
-            {
-               if (dsp_row != NULL)
-                  png_combine_row(png_ptr, dsp_row, 1/*display*/);
-
-               png_read_finish_row(png_ptr);
-               return;
-            }
-            break;
-
-         case 4:
-            if ((png_ptr->row_number & 3) != 2)
-            {
-               if (dsp_row != NULL && (png_ptr->row_number & 2))
-                  png_combine_row(png_ptr, dsp_row, 1/*display*/);
-
-               png_read_finish_row(png_ptr);
-               return;
-            }
-            break;
-         case 5:
-            if ((png_ptr->row_number & 1) || png_ptr->width < 2)
-            {
-               if (dsp_row != NULL)
-                  png_combine_row(png_ptr, dsp_row, 1/*display*/);
-
-               png_read_finish_row(png_ptr);
-               return;
-            }
-            break;
-
-         default:
-         case 6:
-            if (!(png_ptr->row_number & 1))
-            {
-               png_read_finish_row(png_ptr);
-               return;
-            }
-            break;
-      }
-   }
-#endif
-
-   if (!(png_ptr->mode & PNG_HAVE_IDAT))
-      dg_png_error(png_ptr, "Invalid attempt to read row data");
-
-   png_ptr->zstream.next_out = png_ptr->row_buf;
-   png_ptr->zstream.avail_out =
-       (uInt)(PNG_ROWBYTES(png_ptr->pixel_depth,
-       png_ptr->iwidth) + 1);
-
-   do
-   {
-      if (!(png_ptr->zstream.avail_in))
-      {
-         while (!png_ptr->idat_size)
-         {
-            png_crc_finish(png_ptr, 0);
-
-            png_ptr->idat_size = png_read_chunk_header(png_ptr);
-            if (png_ptr->chunk_name != png_IDAT)
-               dg_png_error(png_ptr, "Not enough image data");
-         }
-         png_ptr->zstream.avail_in = (uInt)png_ptr->zbuf_size;
-         png_ptr->zstream.next_in = png_ptr->zbuf;
-         if (png_ptr->zbuf_size > png_ptr->idat_size)
-            png_ptr->zstream.avail_in = (uInt)png_ptr->idat_size;
-         png_crc_read(png_ptr, png_ptr->zbuf,
-             (png_size_t)png_ptr->zstream.avail_in);
-         png_ptr->idat_size -= png_ptr->zstream.avail_in;
-      }
-
-      ret = inflate(&png_ptr->zstream, Z_PARTIAL_FLUSH);
-
-      if (ret == Z_STREAM_END)
-      {
-         if (png_ptr->zstream.avail_out || png_ptr->zstream.avail_in ||
-            png_ptr->idat_size)
-            png_benign_error(png_ptr, "Extra compressed data");
-         png_ptr->mode |= PNG_AFTER_IDAT;
-         png_ptr->flags |= PNG_FLAG_ZLIB_FINISHED;
-         break;
-      }
-
-      if (ret != Z_OK)
-         dg_png_error(png_ptr, png_ptr->zstream.msg ? png_ptr->zstream.msg :
-             "Decompression error");
-
-   } while (png_ptr->zstream.avail_out);
-
-   if (png_ptr->row_buf[0] > PNG_FILTER_VALUE_NONE)
-   {
-      if (png_ptr->row_buf[0] < PNG_FILTER_VALUE_LAST)
-         png_read_filter_row(png_ptr, &row_info, png_ptr->row_buf + 1,
-            png_ptr->prev_row + 1, png_ptr->row_buf[0]);
-      else
-         dg_png_error(png_ptr, "bad adaptive filter value");
-   }
-
-   /* libpng 1.5.6: the following line was copying png_ptr->rowbytes before
-    * 1.5.6, while the buffer really is this big in current versions of libpng
-    * it may not be in the future, so this was changed just to copy the
-    * interlaced count:
-    */
-   png_memcpy(png_ptr->prev_row, png_ptr->row_buf, row_info.rowbytes + 1);
-
-#ifdef PNG_MNG_FEATURES_SUPPORTED
-   if ((png_ptr->mng_features_permitted & PNG_FLAG_MNG_FILTER_64) &&
-       (png_ptr->filter_type == PNG_INTRAPIXEL_DIFFERENCING))
-   {
-      /* Intrapixel differencing */
-      png_do_read_intrapixel(&row_info, png_ptr->row_buf + 1);
-   }
-#endif
-
-
-#ifdef PNG_READ_TRANSFORMS_SUPPORTED
-   if (png_ptr->transformations)
-      png_do_read_transformations(png_ptr, &row_info);
-#endif
-
-   /* The transformed pixel depth should match the depth now in row_info. */
-   if (png_ptr->transformed_pixel_depth == 0)
-   {
-      png_ptr->transformed_pixel_depth = row_info.pixel_depth;
-      if (row_info.pixel_depth > png_ptr->maximum_pixel_depth)
-         dg_png_error(png_ptr, "sequential row overflow");
-   }
-
-   else if (png_ptr->transformed_pixel_depth != row_info.pixel_depth)
-      dg_png_error(png_ptr, "internal sequential row size calculation error");
-
-#ifdef PNG_READ_INTERLACING_SUPPORTED
-   /* Blow up interlaced rows to full size */
-   if (png_ptr->interlaced &&
-      (png_ptr->transformations & PNG_INTERLACE))
-   {
-      if (png_ptr->pass < 6)
-         png_do_read_interlace(&row_info, png_ptr->row_buf + 1, png_ptr->pass,
-            png_ptr->transformations);
-
-      if (dsp_row != NULL)
-         png_combine_row(png_ptr, dsp_row, 1/*display*/);
-
-      if (row != NULL)
-         png_combine_row(png_ptr, row, 0/*row*/);
-   }
-
-   else
-#endif
-   {
-      if (row != NULL)
-         png_combine_row(png_ptr, row, -1/*ignored*/);
-
-      if (dsp_row != NULL)
-         png_combine_row(png_ptr, dsp_row, -1/*ignored*/);
-   }
-   png_read_finish_row(png_ptr);
-
-   if (png_ptr->read_row_fn != NULL)
-      (*(png_ptr->read_row_fn))(png_ptr, png_ptr->row_number, png_ptr->pass);
-}
-#endif /* PNG_SEQUENTIAL_READ_SUPPORTED */
-
-#ifdef PNG_SEQUENTIAL_READ_SUPPORTED
-/* Read one or more rows of image data.  If the image is interlaced,
- * and png_set_interlace_handling() has been called, the rows need to
- * contain the contents of the rows from the previous pass.  If the
- * image has alpha or transparency, and png_handle_alpha()[*] has been
- * called, the rows contents must be initialized to the contents of the
- * screen.
- *
- * "row" holds the actual image, and pixels are placed in it
- * as they arrive.  If the image is displayed after each pass, it will
- * appear to "sparkle" in.  "display_row" can be used to display a
- * "chunky" progressive image, with finer detail added as it becomes
- * available.  If you do not want this "chunky" display, you may pass
- * NULL for display_row.  If you do not want the sparkle display, and
- * you have not called png_handle_alpha(), you may pass NULL for rows.
- * If you have called png_handle_alpha(), and the image has either an
- * alpha channel or a transparency chunk, you must provide a buffer for
- * rows.  In this case, you do not have to provide a display_row buffer
- * also, but you may.  If the image is not interlaced, or if you have
- * not called png_set_interlace_handling(), the display_row buffer will
- * be ignored, so pass NULL to it.
- *
- * [*] png_handle_alpha() does not exist yet, as of this version of libpng
- */
-
-void PNGAPI
-png_read_rows(png_structp png_ptr, png_bytepp row,
-    png_bytepp display_row, png_uint_32 num_rows)
-{
-   png_uint_32 i;
-   png_bytepp rp;
-   png_bytepp dp;
-
-   png_debug(1, "in png_read_rows");
-
-   if (png_ptr == NULL)
-      return;
-
-   rp = row;
-   dp = display_row;
-   if (rp != NULL && dp != NULL)
-      for (i = 0; i < num_rows; i++)
-      {
-         png_bytep rptr = *rp++;
-         png_bytep dptr = *dp++;
-
-         png_read_row(png_ptr, rptr, dptr);
-      }
-
-   else if (rp != NULL)
-      for (i = 0; i < num_rows; i++)
-      {
-         png_bytep rptr = *rp;
-         png_read_row(png_ptr, rptr, NULL);
-         rp++;
-      }
-
-   else if (dp != NULL)
-      for (i = 0; i < num_rows; i++)
-      {
-         png_bytep dptr = *dp;
-         png_read_row(png_ptr, NULL, dptr);
-         dp++;
-      }
-}
-#endif /* PNG_SEQUENTIAL_READ_SUPPORTED */
-
-#ifdef PNG_SEQUENTIAL_READ_SUPPORTED
-/* Read the entire image.  If the image has an alpha channel or a tRNS
- * chunk, and you have called png_handle_alpha()[*], you will need to
- * initialize the image to the current image that PNG will be overlaying.
- * We set the num_rows again here, in case it was incorrectly set in
- * png_read_start_row() by a call to png_read_update_info() or
- * png_start_read_image() if png_set_interlace_handling() wasn't called
- * prior to either of these functions like it should have been.  You can
- * only call this function once.  If you desire to have an image for
- * each pass of a interlaced image, use png_read_rows() instead.
- *
- * [*] png_handle_alpha() does not exist yet, as of this version of libpng
- */
-void PNGAPI
-dg_png_read_image(png_structp png_ptr, png_bytepp image)
-{
-   png_uint_32 i, image_height;
-   int pass, j;
-   png_bytepp rp;
-
-   png_debug(1, "in png_read_image");
-
-   if (png_ptr == NULL)
-      return;
-
-#ifdef PNG_READ_INTERLACING_SUPPORTED
-   if (!(png_ptr->flags & PNG_FLAG_ROW_INIT))
-   {
-      pass = dg_png_set_interlace_handling(png_ptr);
-      /* And make sure transforms are initialized. */
-      png_start_read_image(png_ptr);
-   }
-   else
-   {
-      if (png_ptr->interlaced && !(png_ptr->transformations & PNG_INTERLACE))
-      {
-         /* Caller called png_start_read_image or png_read_update_info without
-          * first turning on the PNG_INTERLACE transform.  We can fix this here,
-          * but the caller should do it!
-          */
-         png_warning(png_ptr, "Interlace handling should be turned on when "
-            "using png_read_image");
-         /* Make sure this is set correctly */
-         png_ptr->num_rows = png_ptr->height;
-      }
-
-      /* Obtain the pass number, which also turns on the PNG_INTERLACE flag in
-       * the above error case.
-       */
-      pass = dg_png_set_interlace_handling(png_ptr);
-   }
-#else
-   if (png_ptr->interlaced)
-      dg_png_error(png_ptr,
-          "Cannot read interlaced image -- interlace handler disabled");
-
-   pass = 1;
-#endif
-
-   image_height=png_ptr->height;
-
-   for (j = 0; j < pass; j++)
-   {
-      rp = image;
-      for (i = 0; i < image_height; i++)
-      {
-         png_read_row(png_ptr, *rp, NULL);
-         rp++;
-      }
-   }
-}
-#endif /* PNG_SEQUENTIAL_READ_SUPPORTED */
-
-#ifdef PNG_SEQUENTIAL_READ_SUPPORTED
-/* Read the end of the PNG file.  Will not read past the end of the
- * file, will verify the end is accurate, and will read any comments
- * or time information at the end of the file, if info is not NULL.
- */
-void PNGAPI
-png_read_end(png_structp png_ptr, png_infop info_ptr)
-{
-   png_debug(1, "in png_read_end");
-
-   if (png_ptr == NULL)
-      return;
-
-   png_crc_finish(png_ptr, 0); /* Finish off CRC from last IDAT chunk */
-
-#ifdef PNG_READ_CHECK_FOR_INVALID_INDEX_SUPPORTED
-   /* Report invalid palette index; added at libng-1.5.10 */
-   if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE &&
-      png_ptr->num_palette_max > png_ptr->num_palette)
-     png_benign_error(png_ptr, "Read palette index exceeding num_palette");
-#endif
-
-   do
-   {
-      png_uint_32 length = png_read_chunk_header(png_ptr);
-      png_uint_32 chunk_name = png_ptr->chunk_name;
-
-      if (chunk_name == png_IHDR)
-         png_handle_IHDR(png_ptr, info_ptr, length);
-
-      else if (chunk_name == png_IEND)
-         png_handle_IEND(png_ptr, info_ptr, length);
-
-#ifdef PNG_HANDLE_AS_UNKNOWN_SUPPORTED
-      else if (png_chunk_unknown_handling(png_ptr, chunk_name) !=
-         PNG_HANDLE_CHUNK_AS_DEFAULT)
-      {
-         if (chunk_name == png_IDAT)
-         {
-            if ((length > 0) || (png_ptr->mode & PNG_HAVE_CHUNK_AFTER_IDAT))
-               png_benign_error(png_ptr, "Too many IDATs found");
-         }
-         png_handle_unknown(png_ptr, info_ptr, length);
-         if (chunk_name == png_PLTE)
-            png_ptr->mode |= PNG_HAVE_PLTE;
-      }
-#endif
-
-      else if (chunk_name == png_IDAT)
-      {
-         /* Zero length IDATs are legal after the last IDAT has been
-          * read, but not after other chunks have been read.
-          */
-         if ((length > 0) || (png_ptr->mode & PNG_HAVE_CHUNK_AFTER_IDAT))
-            png_benign_error(png_ptr, "Too many IDATs found");
-
-         png_crc_finish(png_ptr, length);
-      }
-      else if (chunk_name == png_PLTE)
-         png_handle_PLTE(png_ptr, info_ptr, length);
-
-#ifdef PNG_READ_bKGD_SUPPORTED
-      else if (chunk_name == png_bKGD)
-         png_handle_bKGD(png_ptr, info_ptr, length);
-#endif
-
-#ifdef PNG_READ_cHRM_SUPPORTED
-      else if (chunk_name == png_cHRM)
-         png_handle_cHRM(png_ptr, info_ptr, length);
-#endif
-
-#ifdef PNG_READ_gAMA_SUPPORTED
-      else if (chunk_name == png_gAMA)
-         png_handle_gAMA(png_ptr, info_ptr, length);
-#endif
-
-#ifdef PNG_READ_hIST_SUPPORTED
-      else if (chunk_name == png_hIST)
-         png_handle_hIST(png_ptr, info_ptr, length);
-#endif
-
-#ifdef PNG_READ_oFFs_SUPPORTED
-      else if (chunk_name == png_oFFs)
-         png_handle_oFFs(png_ptr, info_ptr, length);
-#endif
-
-#ifdef PNG_READ_pCAL_SUPPORTED
-      else if (chunk_name == png_pCAL)
-         png_handle_pCAL(png_ptr, info_ptr, length);
-#endif
-
-#ifdef PNG_READ_sCAL_SUPPORTED
-      else if (chunk_name == png_sCAL)
-         png_handle_sCAL(png_ptr, info_ptr, length);
-#endif
-
-#ifdef PNG_READ_pHYs_SUPPORTED
-      else if (chunk_name == png_pHYs)
-         png_handle_pHYs(png_ptr, info_ptr, length);
-#endif
-
-#ifdef PNG_READ_sBIT_SUPPORTED
-      else if (chunk_name == png_sBIT)
-         png_handle_sBIT(png_ptr, info_ptr, length);
-#endif
-
-#ifdef PNG_READ_sRGB_SUPPORTED
-      else if (chunk_name == png_sRGB)
-         png_handle_sRGB(png_ptr, info_ptr, length);
-#endif
-
-#ifdef PNG_READ_iCCP_SUPPORTED
-      else if (chunk_name == png_iCCP)
-         png_handle_iCCP(png_ptr, info_ptr, length);
-#endif
-
-#ifdef PNG_READ_sPLT_SUPPORTED
-      else if (chunk_name == png_sPLT)
-         png_handle_sPLT(png_ptr, info_ptr, length);
-#endif
-
-#ifdef PNG_READ_tEXt_SUPPORTED
-      else if (chunk_name == png_tEXt)
-         png_handle_tEXt(png_ptr, info_ptr, length);
-#endif
-
-#ifdef PNG_READ_tIME_SUPPORTED
-      else if (chunk_name == png_tIME)
-         png_handle_tIME(png_ptr, info_ptr, length);
-#endif
-
-#ifdef PNG_READ_tRNS_SUPPORTED
-      else if (chunk_name == png_tRNS)
-         png_handle_tRNS(png_ptr, info_ptr, length);
-#endif
-
-#ifdef PNG_READ_zTXt_SUPPORTED
-      else if (chunk_name == png_zTXt)
-         png_handle_zTXt(png_ptr, info_ptr, length);
-#endif
-
-#ifdef PNG_READ_iTXt_SUPPORTED
-      else if (chunk_name == png_iTXt)
-         png_handle_iTXt(png_ptr, info_ptr, length);
-#endif
-
-      else
-         png_handle_unknown(png_ptr, info_ptr, length);
-   } while (!(png_ptr->mode & PNG_HAVE_IEND));
-}
-#endif /* PNG_SEQUENTIAL_READ_SUPPORTED */
-
-/* Free all memory used by the read */
-void PNGAPI
-dg_png_destroy_read_struct(png_structpp png_ptr_ptr, png_infopp info_ptr_ptr,
-    png_infopp end_info_ptr_ptr)
-{
-   png_structp png_ptr = NULL;
-   png_infop info_ptr = NULL, end_info_ptr = NULL;
-#ifdef PNG_USER_MEM_SUPPORTED
-   png_free_ptr free_fn = NULL;
-   png_voidp mem_ptr = NULL;
-#endif
-
-   png_debug(1, "in png_destroy_read_struct");
-
-   if (png_ptr_ptr != NULL)
-      png_ptr = *png_ptr_ptr;
-   if (png_ptr == NULL)
-      return;
-
-#ifdef PNG_USER_MEM_SUPPORTED
-   free_fn = png_ptr->free_fn;
-   mem_ptr = png_ptr->mem_ptr;
-#endif
-
-   if (info_ptr_ptr != NULL)
-      info_ptr = *info_ptr_ptr;
-
-   if (end_info_ptr_ptr != NULL)
-      end_info_ptr = *end_info_ptr_ptr;
-
-   png_read_destroy(png_ptr, info_ptr, end_info_ptr);
-
-   if (info_ptr != NULL)
-   {
-#ifdef PNG_TEXT_SUPPORTED
-      png_free_data(png_ptr, info_ptr, PNG_FREE_TEXT, -1);
-#endif
-
-#ifdef PNG_USER_MEM_SUPPORTED
-      png_destroy_struct_2((png_voidp)info_ptr, (png_free_ptr)free_fn,
-          (png_voidp)mem_ptr);
-#else
-      png_destroy_struct((png_voidp)info_ptr);
-#endif
-      *info_ptr_ptr = NULL;
-   }
-
-   if (end_info_ptr != NULL)
-   {
-#ifdef PNG_READ_TEXT_SUPPORTED
-      png_free_data(png_ptr, end_info_ptr, PNG_FREE_TEXT, -1);
-#endif
-#ifdef PNG_USER_MEM_SUPPORTED
-      png_destroy_struct_2((png_voidp)end_info_ptr, (png_free_ptr)free_fn,
-          (png_voidp)mem_ptr);
-#else
-      png_destroy_struct((png_voidp)end_info_ptr);
-#endif
-      *end_info_ptr_ptr = NULL;
-   }
-
-   if (png_ptr != NULL)
-   {
-#ifdef PNG_USER_MEM_SUPPORTED
-      png_destroy_struct_2((png_voidp)png_ptr, (png_free_ptr)free_fn,
-          (png_voidp)mem_ptr);
-#else
-      png_destroy_struct((png_voidp)png_ptr);
-#endif
-      *png_ptr_ptr = NULL;
-   }
-}
-
-/* Free all memory used by the read (old method) */
-void /* PRIVATE */
-png_read_destroy(png_structp png_ptr, png_infop info_ptr,
-    png_infop end_info_ptr)
-{
-#ifdef PNG_SETJMP_SUPPORTED
-   jmp_buf tmp_jmp;
-#endif
-   png_error_ptr error_fn;
-#ifdef PNG_WARNINGS_SUPPORTED
-   png_error_ptr warning_fn;
-#endif
-   png_voidp error_ptr;
-#ifdef PNG_USER_MEM_SUPPORTED
-   png_free_ptr free_fn;
-#endif
-
-   png_debug(1, "in png_read_destroy");
-
-   if (info_ptr != NULL)
-      png_info_destroy(png_ptr, info_ptr);
-
-   if (end_info_ptr != NULL)
-      png_info_destroy(png_ptr, end_info_ptr);
-
-#ifdef PNG_READ_GAMMA_SUPPORTED
-   png_destroy_gamma_table(png_ptr);
-#endif
-
-   png_free(png_ptr, png_ptr->zbuf);
-   png_free(png_ptr, png_ptr->big_row_buf);
-   png_free(png_ptr, png_ptr->big_prev_row);
-   png_free(png_ptr, png_ptr->chunkdata);
-
-#ifdef PNG_READ_QUANTIZE_SUPPORTED
-   png_free(png_ptr, png_ptr->palette_lookup);
-   png_free(png_ptr, png_ptr->quantize_index);
-#endif
-
-   if (png_ptr->free_me & PNG_FREE_PLTE)
-      png_zfree(png_ptr, png_ptr->palette);
-   png_ptr->free_me &= ~PNG_FREE_PLTE;
-
-#if defined(PNG_tRNS_SUPPORTED) || \
-    defined(PNG_READ_EXPAND_SUPPORTED) || defined(PNG_READ_BACKGROUND_SUPPORTED)
-   if (png_ptr->free_me & PNG_FREE_TRNS)
-      png_free(png_ptr, png_ptr->trans_alpha);
-   png_ptr->free_me &= ~PNG_FREE_TRNS;
-#endif
-
-#ifdef PNG_READ_hIST_SUPPORTED
-   if (png_ptr->free_me & PNG_FREE_HIST)
-      png_free(png_ptr, png_ptr->hist);
-   png_ptr->free_me &= ~PNG_FREE_HIST;
-#endif
-
-   inflateEnd(&png_ptr->zstream);
-
-#ifdef PNG_PROGRESSIVE_READ_SUPPORTED
-   png_free(png_ptr, png_ptr->save_buffer);
-#endif
-
-   /* Save the important info out of the png_struct, in case it is
-    * being used again.
-    */
-#ifdef PNG_SETJMP_SUPPORTED
-   png_memcpy(tmp_jmp, png_ptr->longjmp_buffer, png_sizeof(jmp_buf));
-#endif
-
-   error_fn = png_ptr->error_fn;
-#ifdef PNG_WARNINGS_SUPPORTED
-   warning_fn = png_ptr->warning_fn;
-#endif
-   error_ptr = png_ptr->error_ptr;
-#ifdef PNG_USER_MEM_SUPPORTED
-   free_fn = png_ptr->free_fn;
-#endif
-
-   png_memset(png_ptr, 0, png_sizeof(png_struct));
-
-   png_ptr->error_fn = error_fn;
-#ifdef PNG_WARNINGS_SUPPORTED
-   png_ptr->warning_fn = warning_fn;
-#endif
-   png_ptr->error_ptr = error_ptr;
-#ifdef PNG_USER_MEM_SUPPORTED
-   png_ptr->free_fn = free_fn;
-#endif
-
-#ifdef PNG_SETJMP_SUPPORTED
-   png_memcpy(png_ptr->longjmp_buffer, tmp_jmp, png_sizeof(jmp_buf));
-#endif
-
-}
-
-void PNGAPI
-png_set_read_status_fn(png_structp png_ptr, png_read_status_ptr read_row_fn)
-{
-   if (png_ptr == NULL)
-      return;
-
-   png_ptr->read_row_fn = read_row_fn;
-}
-
-
-#ifdef PNG_SEQUENTIAL_READ_SUPPORTED
-#ifdef PNG_INFO_IMAGE_SUPPORTED
-void PNGAPI
-png_read_png(png_structp png_ptr, png_infop info_ptr,
-                           int transforms,
-                           voidp params)
-{
-   int row;
-
-   if (png_ptr == NULL || info_ptr == NULL)
-      return;
-
-   /* png_read_info() gives us all of the information from the
-    * PNG file before the first IDAT (image data chunk).
-    */
-   dg_png_read_info(png_ptr, info_ptr);
-   if (info_ptr->height > PNG_UINT_32_MAX/png_sizeof(png_bytep))
-      dg_png_error(png_ptr, "Image is too high to process with png_read_png()");
-
-   /* -------------- image transformations start here ------------------- */
-
-#ifdef PNG_READ_SCALE_16_TO_8_SUPPORTED
-   /* Tell libpng to strip 16-bit/color files down to 8 bits per color.
-    */
-   if (transforms & PNG_TRANSFORM_SCALE_16)
-   {
-     /* Added at libpng-1.5.4. "strip_16" produces the same result that it
-      * did in earlier versions, while "scale_16" is now more accurate.
-      */
-      png_set_scale_16(png_ptr);
-   }
-#endif
-
-#ifdef PNG_READ_STRIP_16_TO_8_SUPPORTED
-   /* If both SCALE and STRIP are required pngrtran will effectively cancel the
-    * latter by doing SCALE first.  This is ok and allows apps not to check for
-    * which is supported to get the right answer.
-    */
-   if (transforms & PNG_TRANSFORM_STRIP_16)
-      png_set_strip_16(png_ptr);
-#endif
-
-#ifdef PNG_READ_STRIP_ALPHA_SUPPORTED
-   /* Strip alpha bytes from the input data without combining with
-    * the background (not recommended).
-    */
-   if (transforms & PNG_TRANSFORM_STRIP_ALPHA)
-      png_set_strip_alpha(png_ptr);
-#endif
-
-#if defined(PNG_READ_PACK_SUPPORTED) && !defined(PNG_READ_EXPAND_SUPPORTED)
-   /* Extract multiple pixels with bit depths of 1, 2, or 4 from a single
-    * byte into separate bytes (useful for paletted and grayscale images).
-    */
-   if (transforms & PNG_TRANSFORM_PACKING)
-      png_set_packing(png_ptr);
-#endif
-
-#ifdef PNG_READ_PACKSWAP_SUPPORTED
-   /* Change the order of packed pixels to least significant bit first
-    * (not useful if you are using png_set_packing).
-    */
-   if (transforms & PNG_TRANSFORM_PACKSWAP)
-      png_set_packswap(png_ptr);
-#endif
-
-#ifdef PNG_READ_EXPAND_SUPPORTED
-   /* Expand paletted colors into true RGB triplets
-    * Expand grayscale images to full 8 bits from 1, 2, or 4 bits/pixel
-    * Expand paletted or RGB images with transparency to full alpha
-    * channels so the data will be available as RGBA quartets.
-    */
-   if (transforms & PNG_TRANSFORM_EXPAND)
-      if ((png_ptr->bit_depth < 8) ||
-          (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE) ||
-          (png_get_valid(png_ptr, info_ptr, PNG_INFO_tRNS)))
-         png_set_expand(png_ptr);
-#endif
-
-   /* We don't handle background color or gamma transformation or quantizing.
-    */
-
-#ifdef PNG_READ_INVERT_SUPPORTED
-   /* Invert monochrome files to have 0 as white and 1 as black
-    */
-   if (transforms & PNG_TRANSFORM_INVERT_MONO)
-      png_set_invert_mono(png_ptr);
-#endif
-
-#ifdef PNG_READ_SHIFT_SUPPORTED
-   /* If you want to shift the pixel values from the range [0,255] or
-    * [0,65535] to the original [0,7] or [0,31], or whatever range the
-    * colors were originally in:
-    */
-   if ((transforms & PNG_TRANSFORM_SHIFT)
-       && png_get_valid(png_ptr, info_ptr, PNG_INFO_sBIT))
-   {
-      png_color_8p sig_bit;
-
-      png_get_sBIT(png_ptr, info_ptr, &sig_bit);
-      png_set_shift(png_ptr, sig_bit);
-   }
-#endif
-
-#ifdef PNG_READ_BGR_SUPPORTED
-   /* Flip the RGB pixels to BGR (or RGBA to BGRA) */
-   if (transforms & PNG_TRANSFORM_BGR)
-      png_set_bgr(png_ptr);
-#endif
-
-#ifdef PNG_READ_SWAP_ALPHA_SUPPORTED
-   /* Swap the RGBA or GA data to ARGB or AG (or BGRA to ABGR) */
-   if (transforms & PNG_TRANSFORM_SWAP_ALPHA)
-      png_set_swap_alpha(png_ptr);
-#endif
-
-#ifdef PNG_READ_SWAP_SUPPORTED
-   /* Swap bytes of 16-bit files to least significant byte first */
-   if (transforms & PNG_TRANSFORM_SWAP_ENDIAN)
-      png_set_swap(png_ptr);
-#endif
-
-/* Added at libpng-1.2.41 */
-#ifdef PNG_READ_INVERT_ALPHA_SUPPORTED
-   /* Invert the alpha channel from opacity to transparency */
-   if (transforms & PNG_TRANSFORM_INVERT_ALPHA)
-      png_set_invert_alpha(png_ptr);
-#endif
-
-/* Added at libpng-1.2.41 */
-#ifdef PNG_READ_GRAY_TO_RGB_SUPPORTED
-   /* Expand grayscale image to RGB */
-   if (transforms & PNG_TRANSFORM_GRAY_TO_RGB)
-      png_set_gray_to_rgb(png_ptr);
-#endif
-
-/* Added at libpng-1.5.4 */
-#ifdef PNG_READ_EXPAND_16_SUPPORTED
-   if (transforms & PNG_TRANSFORM_EXPAND_16)
-      png_set_expand_16(png_ptr);
-#endif
-
-   /* We don't handle adding filler bytes */
-
-   /* We use png_read_image and rely on that for interlace handling, but we also
-    * call png_read_update_info therefore must turn on interlace handling now:
-    */
-   (void)dg_png_set_interlace_handling(png_ptr);
-
-   /* Optional call to gamma correct and add the background to the palette
-    * and update info structure.  REQUIRED if you are expecting libpng to
-    * update the palette for you (i.e., you selected such a transform above).
-    */
-   dg_png_read_update_info(png_ptr, info_ptr);
-
-   /* -------------- image transformations end here ------------------- */
-
-   png_free_data(png_ptr, info_ptr, PNG_FREE_ROWS, 0);
-   if (info_ptr->row_pointers == NULL)
-   {
-      png_uint_32 iptr;
-
-      info_ptr->row_pointers = (png_bytepp)png_malloc(png_ptr,
-          info_ptr->height * png_sizeof(png_bytep));
-      for (iptr=0; iptr<info_ptr->height; iptr++)
-         info_ptr->row_pointers[iptr] = NULL;
-
-      info_ptr->free_me |= PNG_FREE_ROWS;
-
-      for (row = 0; row < (int)info_ptr->height; row++)
-         info_ptr->row_pointers[row] = (png_bytep)png_malloc(png_ptr,
-            dg_png_get_rowbytes(png_ptr, info_ptr));
-   }
-
-   dg_png_read_image(png_ptr, info_ptr->row_pointers);
-   info_ptr->valid |= PNG_INFO_IDAT;
-
-   /* Read rest of file, and get additional chunks in info_ptr - REQUIRED */
-   png_read_end(png_ptr, info_ptr);
-
-   PNG_UNUSED(transforms)   /* Quiet compiler warnings */
-   PNG_UNUSED(params)
-
-}
-#endif /* PNG_INFO_IMAGE_SUPPORTED */
-#endif /* PNG_SEQUENTIAL_READ_SUPPORTED */
-#endif /* PNG_READ_SUPPORTED */
diff --git a/plugingui/png/pngrio.c b/plugingui/png/pngrio.c
deleted file mode 100644
index e45df21..0000000
--- a/plugingui/png/pngrio.c
+++ /dev/null
@@ -1,176 +0,0 @@
-
-/* pngrio.c - functions for data input
- *
- * Last changed in libpng 1.5.0 [January 6, 2011]
- * Copyright (c) 1998-2011 Glenn Randers-Pehrson
- * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
- * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)
- *
- * This code is released under the libpng license.
- * For conditions of distribution and use, see the disclaimer
- * and license in png.h
- *
- * This file provides a location for all input.  Users who need
- * special handling are expected to write a function that has the same
- * arguments as this and performs a similar function, but that possibly
- * has a different input method.  Note that you shouldn't change this
- * function, but rather write a replacement function and then make
- * libpng use it at run time with png_set_read_fn(...).
- */
-
-#include "pngpriv.h"
-
-#ifdef PNG_READ_SUPPORTED
-
-/* Read the data from whatever input you are using.  The default routine
- * reads from a file pointer.  Note that this routine sometimes gets called
- * with very small lengths, so you should implement some kind of simple
- * buffering if you are using unbuffered reads.  This should never be asked
- * to read more then 64K on a 16 bit machine.
- */
-void /* PRIVATE */
-png_read_data(png_structp png_ptr, png_bytep data, png_size_t length)
-{
-   png_debug1(4, "reading %d bytes", (int)length);
-
-   if (png_ptr->read_data_fn != NULL)
-      (*(png_ptr->read_data_fn))(png_ptr, data, length);
-
-   else
-      dg_png_error(png_ptr, "Call to NULL read function");
-}
-
-#ifdef PNG_STDIO_SUPPORTED
-/* This is the function that does the actual reading of data.  If you are
- * not reading from a standard C stream, you should create a replacement
- * read_data function and use it at run time with png_set_read_fn(), rather
- * than changing the library.
- */
-#  ifndef USE_FAR_KEYWORD
-void PNGCBAPI
-png_default_read_data(png_structp png_ptr, png_bytep data, png_size_t length)
-{
-   png_size_t check;
-
-   if (png_ptr == NULL)
-      return;
-
-   /* fread() returns 0 on error, so it is OK to store this in a png_size_t
-    * instead of an int, which is what fread() actually returns.
-    */
-   check = fread(data, 1, length, (png_FILE_p)png_ptr->io_ptr);
-
-   if (check != length)
-      dg_png_error(png_ptr, "Read Error");
-}
-#  else
-/* This is the model-independent version. Since the standard I/O library
-   can't handle far buffers in the medium and small models, we have to copy
-   the data.
-*/
-
-#define NEAR_BUF_SIZE 1024
-#define MIN(a,b) (a <= b ? a : b)
-
-static void PNGCBAPI
-png_default_read_data(png_structp png_ptr, png_bytep data, png_size_t length)
-{
-   png_size_t check;
-   png_byte *n_data;
-   png_FILE_p io_ptr;
-
-   if (png_ptr == NULL)
-      return;
-
-   /* Check if data really is near. If so, use usual code. */
-   n_data = (png_byte *)CVT_PTR_NOCHECK(data);
-   io_ptr = (png_FILE_p)CVT_PTR(png_ptr->io_ptr);
-
-   if ((png_bytep)n_data == data)
-   {
-      check = fread(n_data, 1, length, io_ptr);
-   }
-
-   else
-   {
-      png_byte buf[NEAR_BUF_SIZE];
-      png_size_t read, remaining, err;
-      check = 0;
-      remaining = length;
-
-      do
-      {
-         read = MIN(NEAR_BUF_SIZE, remaining);
-         err = fread(buf, 1, read, io_ptr);
-         png_memcpy(data, buf, read); /* copy far buffer to near buffer */
-
-         if (err != read)
-            break;
-
-         else
-            check += err;
-
-         data += read;
-         remaining -= read;
-      }
-      while (remaining != 0);
-   }
-
-   if ((png_uint_32)check != (png_uint_32)length)
-      dg_png_error(png_ptr, "read Error");
-}
-#  endif
-#endif
-
-/* This function allows the application to supply a new input function
- * for libpng if standard C streams aren't being used.
- *
- * This function takes as its arguments:
- *
- * png_ptr      - pointer to a png input data structure
- *
- * io_ptr       - pointer to user supplied structure containing info about
- *                the input functions.  May be NULL.
- *
- * read_data_fn - pointer to a new input function that takes as its
- *                arguments a pointer to a png_struct, a pointer to
- *                a location where input data can be stored, and a 32-bit
- *                unsigned int that is the number of bytes to be read.
- *                To exit and output any fatal error messages the new write
- *                function should call png_error(png_ptr, "Error msg").
- *                May be NULL, in which case libpng's default function will
- *                be used.
- */
-void PNGAPI
-dg_png_set_read_fn(png_structp png_ptr, png_voidp io_ptr,
-   png_rw_ptr read_data_fn)
-{
-   if (png_ptr == NULL)
-      return;
-
-   png_ptr->io_ptr = io_ptr;
-
-#ifdef PNG_STDIO_SUPPORTED
-   if (read_data_fn != NULL)
-      png_ptr->read_data_fn = read_data_fn;
-
-   else
-      png_ptr->read_data_fn = png_default_read_data;
-#else
-   png_ptr->read_data_fn = read_data_fn;
-#endif
-
-   /* It is an error to write to a read device */
-   if (png_ptr->write_data_fn != NULL)
-   {
-      png_ptr->write_data_fn = NULL;
-      png_warning(png_ptr,
-          "Can't set both read_data_fn and write_data_fn in the"
-          " same structure");
-   }
-
-#ifdef PNG_WRITE_FLUSH_SUPPORTED
-   png_ptr->output_flush_fn = NULL;
-#endif
-}
-#endif /* PNG_READ_SUPPORTED */
diff --git a/plugingui/png/pngrtran.c b/plugingui/png/pngrtran.c
deleted file mode 100644
index 33e0d30..0000000
--- a/plugingui/png/pngrtran.c
+++ /dev/null
@@ -1,5054 +0,0 @@
-
-/* pngrtran.c - transforms the data in a row for PNG readers
- *
- * Last changed in libpng 1.5.11 [June 14, 2012]
- * Copyright (c) 1998-2012 Glenn Randers-Pehrson
- * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
- * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)
- *
- * This code is released under the libpng license.
- * For conditions of distribution and use, see the disclaimer
- * and license in png.h
- *
- * This file contains functions optionally called by an application
- * in order to tell libpng how to handle data when reading a PNG.
- * Transformations that are used in both reading and writing are
- * in pngtrans.c.
- */
-
-#include "pngpriv.h"
-
-#ifdef PNG_READ_SUPPORTED
-
-/* Set the action on getting a CRC error for an ancillary or critical chunk. */
-void PNGAPI
-png_set_crc_action(png_structp png_ptr, int crit_action, int ancil_action)
-{
-   png_debug(1, "in png_set_crc_action");
-
-   if (png_ptr == NULL)
-      return;
-
-   /* Tell libpng how we react to CRC errors in critical chunks */
-   switch (crit_action)
-   {
-      case PNG_CRC_NO_CHANGE:                        /* Leave setting as is */
-         break;
-
-      case PNG_CRC_WARN_USE:                               /* Warn/use data */
-         png_ptr->flags &= ~PNG_FLAG_CRC_CRITICAL_MASK;
-         png_ptr->flags |= PNG_FLAG_CRC_CRITICAL_USE;
-         break;
-
-      case PNG_CRC_QUIET_USE:                             /* Quiet/use data */
-         png_ptr->flags &= ~PNG_FLAG_CRC_CRITICAL_MASK;
-         png_ptr->flags |= PNG_FLAG_CRC_CRITICAL_USE |
-                           PNG_FLAG_CRC_CRITICAL_IGNORE;
-         break;
-
-      case PNG_CRC_WARN_DISCARD:    /* Not a valid action for critical data */
-         png_warning(png_ptr,
-            "Can't discard critical data on CRC error");
-      case PNG_CRC_ERROR_QUIT:                                /* Error/quit */
-
-      case PNG_CRC_DEFAULT:
-      default:
-         png_ptr->flags &= ~PNG_FLAG_CRC_CRITICAL_MASK;
-         break;
-   }
-
-   /* Tell libpng how we react to CRC errors in ancillary chunks */
-   switch (ancil_action)
-   {
-      case PNG_CRC_NO_CHANGE:                       /* Leave setting as is */
-         break;
-
-      case PNG_CRC_WARN_USE:                              /* Warn/use data */
-         png_ptr->flags &= ~PNG_FLAG_CRC_ANCILLARY_MASK;
-         png_ptr->flags |= PNG_FLAG_CRC_ANCILLARY_USE;
-         break;
-
-      case PNG_CRC_QUIET_USE:                            /* Quiet/use data */
-         png_ptr->flags &= ~PNG_FLAG_CRC_ANCILLARY_MASK;
-         png_ptr->flags |= PNG_FLAG_CRC_ANCILLARY_USE |
-                           PNG_FLAG_CRC_ANCILLARY_NOWARN;
-         break;
-
-      case PNG_CRC_ERROR_QUIT:                               /* Error/quit */
-         png_ptr->flags &= ~PNG_FLAG_CRC_ANCILLARY_MASK;
-         png_ptr->flags |= PNG_FLAG_CRC_ANCILLARY_NOWARN;
-         break;
-
-      case PNG_CRC_WARN_DISCARD:                      /* Warn/discard data */
-
-      case PNG_CRC_DEFAULT:
-      default:
-         png_ptr->flags &= ~PNG_FLAG_CRC_ANCILLARY_MASK;
-         break;
-   }
-}
-
-#ifdef PNG_READ_BACKGROUND_SUPPORTED
-/* Handle alpha and tRNS via a background color */
-void PNGFAPI
-png_set_background_fixed(png_structp png_ptr,
-    png_const_color_16p background_color, int background_gamma_code,
-    int need_expand, png_fixed_point background_gamma)
-{
-   png_debug(1, "in png_set_background_fixed");
-
-   if (png_ptr == NULL)
-      return;
-
-   if (background_gamma_code == PNG_BACKGROUND_GAMMA_UNKNOWN)
-   {
-      png_warning(png_ptr, "Application must supply a known background gamma");
-      return;
-   }
-
-   png_ptr->transformations |= PNG_COMPOSE | PNG_STRIP_ALPHA;
-   png_ptr->transformations &= ~PNG_ENCODE_ALPHA;
-   png_ptr->flags &= ~PNG_FLAG_OPTIMIZE_ALPHA;
-
-   png_memcpy(&(png_ptr->background), background_color,
-      png_sizeof(png_color_16));
-   png_ptr->background_gamma = background_gamma;
-   png_ptr->background_gamma_type = (png_byte)(background_gamma_code);
-   if (need_expand)
-      png_ptr->transformations |= PNG_BACKGROUND_EXPAND;
-   else
-      png_ptr->transformations &= ~PNG_BACKGROUND_EXPAND;
-}
-
-#  ifdef PNG_FLOATING_POINT_SUPPORTED
-void PNGAPI
-png_set_background(png_structp png_ptr,
-    png_const_color_16p background_color, int background_gamma_code,
-    int need_expand, double background_gamma)
-{
-   png_set_background_fixed(png_ptr, background_color, background_gamma_code,
-      need_expand, png_fixed(png_ptr, background_gamma, "png_set_background"));
-}
-#  endif  /* FLOATING_POINT */
-#endif /* READ_BACKGROUND */
-
-/* Scale 16-bit depth files to 8-bit depth.  If both of these are set then the
- * one that pngrtran does first (scale) happens.  This is necessary to allow the
- * TRANSFORM and API behavior to be somewhat consistent, and it's simpler.
- */
-#ifdef PNG_READ_SCALE_16_TO_8_SUPPORTED
-void PNGAPI
-png_set_scale_16(png_structp png_ptr)
-{
-   png_debug(1, "in png_set_scale_16");
-
-   if (png_ptr == NULL)
-      return;
-
-   png_ptr->transformations |= PNG_SCALE_16_TO_8;
-}
-#endif
-
-#ifdef PNG_READ_STRIP_16_TO_8_SUPPORTED
-/* Chop 16-bit depth files to 8-bit depth */
-void PNGAPI
-png_set_strip_16(png_structp png_ptr)
-{
-   png_debug(1, "in png_set_strip_16");
-
-   if (png_ptr == NULL)
-      return;
-
-   png_ptr->transformations |= PNG_16_TO_8;
-}
-#endif
-
-#ifdef PNG_READ_STRIP_ALPHA_SUPPORTED
-void PNGAPI
-png_set_strip_alpha(png_structp png_ptr)
-{
-   png_debug(1, "in png_set_strip_alpha");
-
-   if (png_ptr == NULL)
-      return;
-
-   png_ptr->transformations |= PNG_STRIP_ALPHA;
-}
-#endif
-
-#if defined(PNG_READ_ALPHA_MODE_SUPPORTED) || defined(PNG_READ_GAMMA_SUPPORTED)
-static png_fixed_point
-translate_gamma_flags(png_structp png_ptr, png_fixed_point output_gamma,
-   int is_screen)
-{
-   /* Check for flag values.  The main reason for having the old Mac value as a
-    * flag is that it is pretty near impossible to work out what the correct
-    * value is from Apple documentation - a working Mac system is needed to
-    * discover the value!
-    */
-   if (output_gamma == PNG_DEFAULT_sRGB ||
-      output_gamma == PNG_FP_1 / PNG_DEFAULT_sRGB)
-   {
-      /* If there is no sRGB support this just sets the gamma to the standard
-       * sRGB value.  (This is a side effect of using this function!)
-       */
-#     ifdef PNG_READ_sRGB_SUPPORTED
-         png_ptr->flags |= PNG_FLAG_ASSUME_sRGB;
-#     endif
-      if (is_screen)
-         output_gamma = PNG_GAMMA_sRGB;
-      else
-         output_gamma = PNG_GAMMA_sRGB_INVERSE;
-   }
-
-   else if (output_gamma == PNG_GAMMA_MAC_18 ||
-      output_gamma == PNG_FP_1 / PNG_GAMMA_MAC_18)
-   {
-      if (is_screen)
-         output_gamma = PNG_GAMMA_MAC_OLD;
-      else
-         output_gamma = PNG_GAMMA_MAC_INVERSE;
-   }
-
-   return output_gamma;
-}
-
-#  ifdef PNG_FLOATING_POINT_SUPPORTED
-static png_fixed_point
-convert_gamma_value(png_structp png_ptr, double output_gamma)
-{
-   /* The following silently ignores cases where fixed point (times 100,000)
-    * gamma values are passed to the floating point API.  This is safe and it
-    * means the fixed point constants work just fine with the floating point
-    * API.  The alternative would just lead to undetected errors and spurious
-    * bug reports.  Negative values fail inside the _fixed API unless they
-    * correspond to the flag values.
-    */
-   if (output_gamma > 0 && output_gamma < 128)
-      output_gamma *= PNG_FP_1;
-
-   /* This preserves -1 and -2 exactly: */
-   output_gamma = floor(output_gamma + .5);
-
-   if (output_gamma > PNG_FP_MAX || output_gamma < PNG_FP_MIN)
-      png_fixed_error(png_ptr, "gamma value");
-
-   return (png_fixed_point)output_gamma;
-}
-#  endif
-#endif /* READ_ALPHA_MODE || READ_GAMMA */
-
-#ifdef PNG_READ_ALPHA_MODE_SUPPORTED
-void PNGFAPI
-png_set_alpha_mode_fixed(png_structp png_ptr, int mode,
-   png_fixed_point output_gamma)
-{
-   int compose = 0;
-   png_fixed_point file_gamma;
-
-   png_debug(1, "in png_set_alpha_mode");
-
-   if (png_ptr == NULL)
-      return;
-
-   output_gamma = translate_gamma_flags(png_ptr, output_gamma, 1/*screen*/);
-
-   /* Validate the value to ensure it is in a reasonable range. The value
-    * is expected to be 1 or greater, but this range test allows for some
-    * viewing correction values.  The intent is to weed out users of this API
-    * who use the inverse of the gamma value accidentally!  Since some of these
-    * values are reasonable this may have to be changed.
-    */
-   if (output_gamma < 70000 || output_gamma > 300000)
-      dg_png_error(png_ptr, "output gamma out of expected range");
-
-   /* The default file gamma is the inverse of the output gamma; the output
-    * gamma may be changed below so get the file value first:
-    */
-   file_gamma = png_reciprocal(output_gamma);
-
-   /* There are really 8 possibilities here, composed of any combination
-    * of:
-    *
-    *    premultiply the color channels
-    *    do not encode non-opaque pixels
-    *    encode the alpha as well as the color channels
-    *
-    * The differences disappear if the input/output ('screen') gamma is 1.0,
-    * because then the encoding is a no-op and there is only the choice of
-    * premultiplying the color channels or not.
-    *
-    * png_set_alpha_mode and png_set_background interact because both use
-    * png_compose to do the work.  Calling both is only useful when
-    * png_set_alpha_mode is used to set the default mode - PNG_ALPHA_PNG - along
-    * with a default gamma value.  Otherwise PNG_COMPOSE must not be set.
-    */
-   switch (mode)
-   {
-      case PNG_ALPHA_PNG:        /* default: png standard */
-         /* No compose, but it may be set by png_set_background! */
-         png_ptr->transformations &= ~PNG_ENCODE_ALPHA;
-         png_ptr->flags &= ~PNG_FLAG_OPTIMIZE_ALPHA;
-         break;
-
-      case PNG_ALPHA_ASSOCIATED: /* color channels premultiplied */
-         compose = 1;
-         png_ptr->transformations &= ~PNG_ENCODE_ALPHA;
-         png_ptr->flags &= ~PNG_FLAG_OPTIMIZE_ALPHA;
-         /* The output is linear: */
-         output_gamma = PNG_FP_1;
-         break;
-
-      case PNG_ALPHA_OPTIMIZED:  /* associated, non-opaque pixels linear */
-         compose = 1;
-         png_ptr->transformations &= ~PNG_ENCODE_ALPHA;
-         png_ptr->flags |= PNG_FLAG_OPTIMIZE_ALPHA;
-         /* output_gamma records the encoding of opaque pixels! */
-         break;
-
-      case PNG_ALPHA_BROKEN:     /* associated, non-linear, alpha encoded */
-         compose = 1;
-         png_ptr->transformations |= PNG_ENCODE_ALPHA;
-         png_ptr->flags &= ~PNG_FLAG_OPTIMIZE_ALPHA;
-         break;
-
-      default:
-         dg_png_error(png_ptr, "invalid alpha mode");
-   }
-
-   /* Only set the default gamma if the file gamma has not been set (this has
-    * the side effect that the gamma in a second call to png_set_alpha_mode will
-    * be ignored.)
-    */
-   if (png_ptr->gamma == 0)
-      png_ptr->gamma = file_gamma;
-
-   /* But always set the output gamma: */
-   png_ptr->screen_gamma = output_gamma;
-
-   /* Finally, if pre-multiplying, set the background fields to achieve the
-    * desired result.
-    */
-   if (compose)
-   {
-      /* And obtain alpha pre-multiplication by composing on black: */
-      png_memset(&png_ptr->background, 0, sizeof png_ptr->background);
-      png_ptr->background_gamma = png_ptr->gamma; /* just in case */
-      png_ptr->background_gamma_type = PNG_BACKGROUND_GAMMA_FILE;
-      png_ptr->transformations &= ~PNG_BACKGROUND_EXPAND;
-
-      if (png_ptr->transformations & PNG_COMPOSE)
-         dg_png_error(png_ptr,
-            "conflicting calls to set alpha mode and background");
-
-      png_ptr->transformations |= PNG_COMPOSE;
-   }
-
-   /* New API, make sure apps call the correct initializers: */
-   png_ptr->flags |= PNG_FLAG_DETECT_UNINITIALIZED;
-}
-
-#  ifdef PNG_FLOATING_POINT_SUPPORTED
-void PNGAPI
-png_set_alpha_mode(png_structp png_ptr, int mode, double output_gamma)
-{
-   png_set_alpha_mode_fixed(png_ptr, mode, convert_gamma_value(png_ptr,
-      output_gamma));
-}
-#  endif
-#endif
-
-#ifdef PNG_READ_QUANTIZE_SUPPORTED
-/* Dither file to 8-bit.  Supply a palette, the current number
- * of elements in the palette, the maximum number of elements
- * allowed, and a histogram if possible.  If the current number
- * of colors is greater then the maximum number, the palette will be
- * modified to fit in the maximum number.  "full_quantize" indicates
- * whether we need a quantizing cube set up for RGB images, or if we
- * simply are reducing the number of colors in a paletted image.
- */
-
-typedef struct png_dsort_struct
-{
-   struct png_dsort_struct FAR * next;
-   png_byte left;
-   png_byte right;
-} png_dsort;
-typedef png_dsort FAR *       png_dsortp;
-typedef png_dsort FAR * FAR * png_dsortpp;
-
-void PNGAPI
-png_set_quantize(png_structp png_ptr, png_colorp palette,
-    int num_palette, int maximum_colors, png_const_uint_16p histogram,
-    int full_quantize)
-{
-   png_debug(1, "in png_set_quantize");
-
-   if (png_ptr == NULL)
-      return;
-
-   png_ptr->transformations |= PNG_QUANTIZE;
-
-   if (!full_quantize)
-   {
-      int i;
-
-      png_ptr->quantize_index = (png_bytep)png_malloc(png_ptr,
-          (png_uint_32)(num_palette * png_sizeof(png_byte)));
-      for (i = 0; i < num_palette; i++)
-         png_ptr->quantize_index[i] = (png_byte)i;
-   }
-
-   if (num_palette > maximum_colors)
-   {
-      if (histogram != NULL)
-      {
-         /* This is easy enough, just throw out the least used colors.
-          * Perhaps not the best solution, but good enough.
-          */
-
-         int i;
-
-         /* Initialize an array to sort colors */
-         png_ptr->quantize_sort = (png_bytep)png_malloc(png_ptr,
-             (png_uint_32)(num_palette * png_sizeof(png_byte)));
-
-         /* Initialize the quantize_sort array */
-         for (i = 0; i < num_palette; i++)
-            png_ptr->quantize_sort[i] = (png_byte)i;
-
-         /* Find the least used palette entries by starting a
-          * bubble sort, and running it until we have sorted
-          * out enough colors.  Note that we don't care about
-          * sorting all the colors, just finding which are
-          * least used.
-          */
-
-         for (i = num_palette - 1; i >= maximum_colors; i--)
-         {
-            int done; /* To stop early if the list is pre-sorted */
-            int j;
-
-            done = 1;
-            for (j = 0; j < i; j++)
-            {
-               if (histogram[png_ptr->quantize_sort[j]]
-                   < histogram[png_ptr->quantize_sort[j + 1]])
-               {
-                  png_byte t;
-
-                  t = png_ptr->quantize_sort[j];
-                  png_ptr->quantize_sort[j] = png_ptr->quantize_sort[j + 1];
-                  png_ptr->quantize_sort[j + 1] = t;
-                  done = 0;
-               }
-            }
-
-            if (done)
-               break;
-         }
-
-         /* Swap the palette around, and set up a table, if necessary */
-         if (full_quantize)
-         {
-            int j = num_palette;
-
-            /* Put all the useful colors within the max, but don't
-             * move the others.
-             */
-            for (i = 0; i < maximum_colors; i++)
-            {
-               if ((int)png_ptr->quantize_sort[i] >= maximum_colors)
-               {
-                  do
-                     j--;
-                  while ((int)png_ptr->quantize_sort[j] >= maximum_colors);
-
-                  palette[i] = palette[j];
-               }
-            }
-         }
-         else
-         {
-            int j = num_palette;
-
-            /* Move all the used colors inside the max limit, and
-             * develop a translation table.
-             */
-            for (i = 0; i < maximum_colors; i++)
-            {
-               /* Only move the colors we need to */
-               if ((int)png_ptr->quantize_sort[i] >= maximum_colors)
-               {
-                  png_color tmp_color;
-
-                  do
-                     j--;
-                  while ((int)png_ptr->quantize_sort[j] >= maximum_colors);
-
-                  tmp_color = palette[j];
-                  palette[j] = palette[i];
-                  palette[i] = tmp_color;
-                  /* Indicate where the color went */
-                  png_ptr->quantize_index[j] = (png_byte)i;
-                  png_ptr->quantize_index[i] = (png_byte)j;
-               }
-            }
-
-            /* Find closest color for those colors we are not using */
-            for (i = 0; i < num_palette; i++)
-            {
-               if ((int)png_ptr->quantize_index[i] >= maximum_colors)
-               {
-                  int min_d, k, min_k, d_index;
-
-                  /* Find the closest color to one we threw out */
-                  d_index = png_ptr->quantize_index[i];
-                  min_d = PNG_COLOR_DIST(palette[d_index], palette[0]);
-                  for (k = 1, min_k = 0; k < maximum_colors; k++)
-                  {
-                     int d;
-
-                     d = PNG_COLOR_DIST(palette[d_index], palette[k]);
-
-                     if (d < min_d)
-                     {
-                        min_d = d;
-                        min_k = k;
-                     }
-                  }
-                  /* Point to closest color */
-                  png_ptr->quantize_index[i] = (png_byte)min_k;
-               }
-            }
-         }
-         png_free(png_ptr, png_ptr->quantize_sort);
-         png_ptr->quantize_sort = NULL;
-      }
-      else
-      {
-         /* This is much harder to do simply (and quickly).  Perhaps
-          * we need to go through a median cut routine, but those
-          * don't always behave themselves with only a few colors
-          * as input.  So we will just find the closest two colors,
-          * and throw out one of them (chosen somewhat randomly).
-          * [We don't understand this at all, so if someone wants to
-          *  work on improving it, be our guest - AED, GRP]
-          */
-         int i;
-         int max_d;
-         int num_new_palette;
-         png_dsortp t;
-         png_dsortpp hash;
-
-         t = NULL;
-
-         /* Initialize palette index arrays */
-         png_ptr->index_to_palette = (png_bytep)png_malloc(png_ptr,
-             (png_uint_32)(num_palette * png_sizeof(png_byte)));
-         png_ptr->palette_to_index = (png_bytep)png_malloc(png_ptr,
-             (png_uint_32)(num_palette * png_sizeof(png_byte)));
-
-         /* Initialize the sort array */
-         for (i = 0; i < num_palette; i++)
-         {
-            png_ptr->index_to_palette[i] = (png_byte)i;
-            png_ptr->palette_to_index[i] = (png_byte)i;
-         }
-
-         hash = (png_dsortpp)png_calloc(png_ptr, (png_uint_32)(769 *
-             png_sizeof(png_dsortp)));
-
-         num_new_palette = num_palette;
-
-         /* Initial wild guess at how far apart the farthest pixel
-          * pair we will be eliminating will be.  Larger
-          * numbers mean more areas will be allocated, Smaller
-          * numbers run the risk of not saving enough data, and
-          * having to do this all over again.
-          *
-          * I have not done extensive checking on this number.
-          */
-         max_d = 96;
-
-         while (num_new_palette > maximum_colors)
-         {
-            for (i = 0; i < num_new_palette - 1; i++)
-            {
-               int j;
-
-               for (j = i + 1; j < num_new_palette; j++)
-               {
-                  int d;
-
-                  d = PNG_COLOR_DIST(palette[i], palette[j]);
-
-                  if (d <= max_d)
-                  {
-
-                     t = (png_dsortp)png_malloc_warn(png_ptr,
-                         (png_uint_32)(png_sizeof(png_dsort)));
-
-                     if (t == NULL)
-                         break;
-
-                     t->next = hash[d];
-                     t->left = (png_byte)i;
-                     t->right = (png_byte)j;
-                     hash[d] = t;
-                  }
-               }
-               if (t == NULL)
-                  break;
-            }
-
-            if (t != NULL)
-            for (i = 0; i <= max_d; i++)
-            {
-               if (hash[i] != NULL)
-               {
-                  png_dsortp p;
-
-                  for (p = hash[i]; p; p = p->next)
-                  {
-                     if ((int)png_ptr->index_to_palette[p->left]
-                         < num_new_palette &&
-                         (int)png_ptr->index_to_palette[p->right]
-                         < num_new_palette)
-                     {
-                        int j, next_j;
-
-                        if (num_new_palette & 0x01)
-                        {
-                           j = p->left;
-                           next_j = p->right;
-                        }
-                        else
-                        {
-                           j = p->right;
-                           next_j = p->left;
-                        }
-
-                        num_new_palette--;
-                        palette[png_ptr->index_to_palette[j]]
-                            = palette[num_new_palette];
-                        if (!full_quantize)
-                        {
-                           int k;
-
-                           for (k = 0; k < num_palette; k++)
-                           {
-                              if (png_ptr->quantize_index[k] ==
-                                  png_ptr->index_to_palette[j])
-                                 png_ptr->quantize_index[k] =
-                                     png_ptr->index_to_palette[next_j];
-
-                              if ((int)png_ptr->quantize_index[k] ==
-                                  num_new_palette)
-                                 png_ptr->quantize_index[k] =
-                                     png_ptr->index_to_palette[j];
-                           }
-                        }
-
-                        png_ptr->index_to_palette[png_ptr->palette_to_index
-                            [num_new_palette]] = png_ptr->index_to_palette[j];
-
-                        png_ptr->palette_to_index[png_ptr->index_to_palette[j]]
-                            = png_ptr->palette_to_index[num_new_palette];
-
-                        png_ptr->index_to_palette[j] =
-                            (png_byte)num_new_palette;
-
-                        png_ptr->palette_to_index[num_new_palette] =
-                            (png_byte)j;
-                     }
-                     if (num_new_palette <= maximum_colors)
-                        break;
-                  }
-                  if (num_new_palette <= maximum_colors)
-                     break;
-               }
-            }
-
-            for (i = 0; i < 769; i++)
-            {
-               if (hash[i] != NULL)
-               {
-                  png_dsortp p = hash[i];
-                  while (p)
-                  {
-                     t = p->next;
-                     png_free(png_ptr, p);
-                     p = t;
-                  }
-               }
-               hash[i] = 0;
-            }
-            max_d += 96;
-         }
-         png_free(png_ptr, hash);
-         png_free(png_ptr, png_ptr->palette_to_index);
-         png_free(png_ptr, png_ptr->index_to_palette);
-         png_ptr->palette_to_index = NULL;
-         png_ptr->index_to_palette = NULL;
-      }
-      num_palette = maximum_colors;
-   }
-   if (png_ptr->palette == NULL)
-   {
-      png_ptr->palette = palette;
-   }
-   png_ptr->num_palette = (png_uint_16)num_palette;
-
-   if (full_quantize)
-   {
-      int i;
-      png_bytep distance;
-      int total_bits = PNG_QUANTIZE_RED_BITS + PNG_QUANTIZE_GREEN_BITS +
-          PNG_QUANTIZE_BLUE_BITS;
-      int num_red = (1 << PNG_QUANTIZE_RED_BITS);
-      int num_green = (1 << PNG_QUANTIZE_GREEN_BITS);
-      int num_blue = (1 << PNG_QUANTIZE_BLUE_BITS);
-      png_size_t num_entries = ((png_size_t)1 << total_bits);
-
-      png_ptr->palette_lookup = (png_bytep)png_calloc(png_ptr,
-          (png_uint_32)(num_entries * png_sizeof(png_byte)));
-
-      distance = (png_bytep)png_malloc(png_ptr, (png_uint_32)(num_entries *
-          png_sizeof(png_byte)));
-
-      png_memset(distance, 0xff, num_entries * png_sizeof(png_byte));
-
-      for (i = 0; i < num_palette; i++)
-      {
-         int ir, ig, ib;
-         int r = (palette[i].red >> (8 - PNG_QUANTIZE_RED_BITS));
-         int g = (palette[i].green >> (8 - PNG_QUANTIZE_GREEN_BITS));
-         int b = (palette[i].blue >> (8 - PNG_QUANTIZE_BLUE_BITS));
-
-         for (ir = 0; ir < num_red; ir++)
-         {
-            /* int dr = abs(ir - r); */
-            int dr = ((ir > r) ? ir - r : r - ir);
-            int index_r = (ir << (PNG_QUANTIZE_BLUE_BITS +
-                PNG_QUANTIZE_GREEN_BITS));
-
-            for (ig = 0; ig < num_green; ig++)
-            {
-               /* int dg = abs(ig - g); */
-               int dg = ((ig > g) ? ig - g : g - ig);
-               int dt = dr + dg;
-               int dm = ((dr > dg) ? dr : dg);
-               int index_g = index_r | (ig << PNG_QUANTIZE_BLUE_BITS);
-
-               for (ib = 0; ib < num_blue; ib++)
-               {
-                  int d_index = index_g | ib;
-                  /* int db = abs(ib - b); */
-                  int db = ((ib > b) ? ib - b : b - ib);
-                  int dmax = ((dm > db) ? dm : db);
-                  int d = dmax + dt + db;
-
-                  if (d < (int)distance[d_index])
-                  {
-                     distance[d_index] = (png_byte)d;
-                     png_ptr->palette_lookup[d_index] = (png_byte)i;
-                  }
-               }
-            }
-         }
-      }
-
-      png_free(png_ptr, distance);
-   }
-}
-#endif /* PNG_READ_QUANTIZE_SUPPORTED */
-
-#ifdef PNG_READ_GAMMA_SUPPORTED
-void PNGFAPI
-png_set_gamma_fixed(png_structp png_ptr, png_fixed_point scrn_gamma,
-   png_fixed_point file_gamma)
-{
-   png_debug(1, "in png_set_gamma_fixed");
-
-   if (png_ptr == NULL)
-      return;
-
-   /* New in libpng-1.5.4 - reserve particular negative values as flags. */
-   scrn_gamma = translate_gamma_flags(png_ptr, scrn_gamma, 1/*screen*/);
-   file_gamma = translate_gamma_flags(png_ptr, file_gamma, 0/*file*/);
-
-#if PNG_LIBPNG_VER >= 10600
-   /* Checking the gamma values for being >0 was added in 1.5.4 along with the
-    * premultiplied alpha support; this actually hides an undocumented feature
-    * of the previous implementation which allowed gamma processing to be
-    * disabled in background handling.  There is no evidence (so far) that this
-    * was being used; however, png_set_background itself accepted and must still
-    * accept '0' for the gamma value it takes, because it isn't always used.
-    *
-    * Since this is an API change (albeit a very minor one that removes an
-    * undocumented API feature) it will not be made until libpng-1.6.0.
-    */
-   if (file_gamma <= 0)
-      dg_png_error(png_ptr, "invalid file gamma in png_set_gamma");
-
-   if (scrn_gamma <= 0)
-      dg_png_error(png_ptr, "invalid screen gamma in png_set_gamma");
-#endif
-
-   /* Set the gamma values unconditionally - this overrides the value in the PNG
-    * file if a gAMA chunk was present.  png_set_alpha_mode provides a
-    * different, easier, way to default the file gamma.
-    */
-   png_ptr->gamma = file_gamma;
-   png_ptr->screen_gamma = scrn_gamma;
-}
-
-#  ifdef PNG_FLOATING_POINT_SUPPORTED
-void PNGAPI
-png_set_gamma(png_structp png_ptr, double scrn_gamma, double file_gamma)
-{
-   png_set_gamma_fixed(png_ptr, convert_gamma_value(png_ptr, scrn_gamma),
-      convert_gamma_value(png_ptr, file_gamma));
-}
-#  endif /* FLOATING_POINT_SUPPORTED */
-#endif /* READ_GAMMA */
-
-#ifdef PNG_READ_EXPAND_SUPPORTED
-/* Expand paletted images to RGB, expand grayscale images of
- * less than 8-bit depth to 8-bit depth, and expand tRNS chunks
- * to alpha channels.
- */
-void PNGAPI
-png_set_expand(png_structp png_ptr)
-{
-   png_debug(1, "in png_set_expand");
-
-   if (png_ptr == NULL)
-      return;
-
-   png_ptr->transformations |= (PNG_EXPAND | PNG_EXPAND_tRNS);
-   png_ptr->flags &= ~PNG_FLAG_ROW_INIT;
-}
-
-/* GRR 19990627:  the following three functions currently are identical
- *  to png_set_expand().  However, it is entirely reasonable that someone
- *  might wish to expand an indexed image to RGB but *not* expand a single,
- *  fully transparent palette entry to a full alpha channel--perhaps instead
- *  convert tRNS to the grayscale/RGB format (16-bit RGB value), or replace
- *  the transparent color with a particular RGB value, or drop tRNS entirely.
- *  IOW, a future version of the library may make the transformations flag
- *  a bit more fine-grained, with separate bits for each of these three
- *  functions.
- *
- *  More to the point, these functions make it obvious what libpng will be
- *  doing, whereas "expand" can (and does) mean any number of things.
- *
- *  GRP 20060307: In libpng-1.2.9, png_set_gray_1_2_4_to_8() was modified
- *  to expand only the sample depth but not to expand the tRNS to alpha
- *  and its name was changed to png_set_expand_gray_1_2_4_to_8().
- */
-
-/* Expand paletted images to RGB. */
-void PNGAPI
-png_set_palette_to_rgb(png_structp png_ptr)
-{
-   png_debug(1, "in png_set_palette_to_rgb");
-
-   if (png_ptr == NULL)
-      return;
-
-   png_ptr->transformations |= (PNG_EXPAND | PNG_EXPAND_tRNS);
-   png_ptr->flags &= ~PNG_FLAG_ROW_INIT;
-}
-
-/* Expand grayscale images of less than 8-bit depth to 8 bits. */
-void PNGAPI
-png_set_expand_gray_1_2_4_to_8(png_structp png_ptr)
-{
-   png_debug(1, "in png_set_expand_gray_1_2_4_to_8");
-
-   if (png_ptr == NULL)
-      return;
-
-   png_ptr->transformations |= PNG_EXPAND;
-   png_ptr->flags &= ~PNG_FLAG_ROW_INIT;
-}
-
-
-
-/* Expand tRNS chunks to alpha channels. */
-void PNGAPI
-png_set_tRNS_to_alpha(png_structp png_ptr)
-{
-   png_debug(1, "in png_set_tRNS_to_alpha");
-
-   png_ptr->transformations |= (PNG_EXPAND | PNG_EXPAND_tRNS);
-   png_ptr->flags &= ~PNG_FLAG_ROW_INIT;
-}
-#endif /* defined(PNG_READ_EXPAND_SUPPORTED) */
-
-#ifdef PNG_READ_EXPAND_16_SUPPORTED
-/* Expand to 16-bit channels, expand the tRNS chunk too (because otherwise
- * it may not work correctly.)
- */
-void PNGAPI
-png_set_expand_16(png_structp png_ptr)
-{
-   png_debug(1, "in png_set_expand_16");
-
-   if (png_ptr == NULL)
-      return;
-
-   png_ptr->transformations |= (PNG_EXPAND_16 | PNG_EXPAND | PNG_EXPAND_tRNS);
-   png_ptr->flags &= ~PNG_FLAG_ROW_INIT;
-
-   /* New API, make sure apps call the correct initializers: */
-   png_ptr->flags |= PNG_FLAG_DETECT_UNINITIALIZED;
-}
-#endif
-
-#ifdef PNG_READ_GRAY_TO_RGB_SUPPORTED
-void PNGAPI
-png_set_gray_to_rgb(png_structp png_ptr)
-{
-   png_debug(1, "in png_set_gray_to_rgb");
-
-   if (png_ptr != NULL)
-   {
-      /* Because rgb must be 8 bits or more: */
-      png_set_expand_gray_1_2_4_to_8(png_ptr);
-      png_ptr->transformations |= PNG_GRAY_TO_RGB;
-      png_ptr->flags &= ~PNG_FLAG_ROW_INIT;
-   }
-}
-#endif
-
-#ifdef PNG_READ_RGB_TO_GRAY_SUPPORTED
-void PNGFAPI
-png_set_rgb_to_gray_fixed(png_structp png_ptr, int error_action,
-    png_fixed_point red, png_fixed_point green)
-{
-   png_debug(1, "in png_set_rgb_to_gray");
-
-   if (png_ptr == NULL)
-      return;
-
-   switch(error_action)
-   {
-      case PNG_ERROR_ACTION_NONE:
-         png_ptr->transformations |= PNG_RGB_TO_GRAY;
-         break;
-
-      case PNG_ERROR_ACTION_WARN:
-         png_ptr->transformations |= PNG_RGB_TO_GRAY_WARN;
-         break;
-
-      case PNG_ERROR_ACTION_ERROR:
-         png_ptr->transformations |= PNG_RGB_TO_GRAY_ERR;
-         break;
-
-      default:
-         dg_png_error(png_ptr, "invalid error action to rgb_to_gray");
-         break;
-   }
-   if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE)
-#ifdef PNG_READ_EXPAND_SUPPORTED
-      png_ptr->transformations |= PNG_EXPAND;
-#else
-   {
-      png_warning(png_ptr,
-        "Cannot do RGB_TO_GRAY without EXPAND_SUPPORTED");
-
-      png_ptr->transformations &= ~PNG_RGB_TO_GRAY;
-   }
-#endif
-   {
-      if (red >= 0 && green >= 0 && red + green <= PNG_FP_1)
-      {
-         png_uint_16 red_int, green_int;
-
-         /* NOTE: this calculation does not round, but this behavior is retained
-          * for consistency, the inaccuracy is very small.  The code here always
-          * overwrites the coefficients, regardless of whether they have been
-          * defaulted or set already.
-          */
-         red_int = (png_uint_16)(((png_uint_32)red*32768)/100000);
-         green_int = (png_uint_16)(((png_uint_32)green*32768)/100000);
-
-         png_ptr->rgb_to_gray_red_coeff   = red_int;
-         png_ptr->rgb_to_gray_green_coeff = green_int;
-         png_ptr->rgb_to_gray_coefficients_set = 1;
-      }
-
-      else
-      {
-         if (red >= 0 && green >= 0)
-            png_warning(png_ptr,
-               "ignoring out of range rgb_to_gray coefficients");
-
-         /* Use the defaults, from the cHRM chunk if set, else the historical
-          * values which are close to the sRGB/HDTV/ITU-Rec 709 values.  See
-          * png_do_rgb_to_gray for more discussion of the values.  In this case
-          * the coefficients are not marked as 'set' and are not overwritten if
-          * something has already provided a default.
-          */
-         if (png_ptr->rgb_to_gray_red_coeff == 0 &&
-            png_ptr->rgb_to_gray_green_coeff == 0)
-         {
-            png_ptr->rgb_to_gray_red_coeff   = 6968;
-            png_ptr->rgb_to_gray_green_coeff = 23434;
-            /* png_ptr->rgb_to_gray_blue_coeff  = 2366; */
-         }
-      }
-   }
-}
-
-#ifdef PNG_FLOATING_POINT_SUPPORTED
-/* Convert a RGB image to a grayscale of the same width.  This allows us,
- * for example, to convert a 24 bpp RGB image into an 8 bpp grayscale image.
- */
-
-void PNGAPI
-png_set_rgb_to_gray(png_structp png_ptr, int error_action, double red,
-   double green)
-{
-   if (png_ptr == NULL)
-      return;
-
-   png_set_rgb_to_gray_fixed(png_ptr, error_action,
-      png_fixed(png_ptr, red, "rgb to gray red coefficient"),
-      png_fixed(png_ptr, green, "rgb to gray green coefficient"));
-}
-#endif /* FLOATING POINT */
-
-#endif
-
-#if defined(PNG_READ_USER_TRANSFORM_SUPPORTED) || \
-    defined(PNG_WRITE_USER_TRANSFORM_SUPPORTED)
-void PNGAPI
-png_set_read_user_transform_fn(png_structp png_ptr, png_user_transform_ptr
-    read_user_transform_fn)
-{
-   png_debug(1, "in png_set_read_user_transform_fn");
-
-   if (png_ptr == NULL)
-      return;
-
-#ifdef PNG_READ_USER_TRANSFORM_SUPPORTED
-   png_ptr->transformations |= PNG_USER_TRANSFORM;
-   png_ptr->read_user_transform_fn = read_user_transform_fn;
-#endif
-}
-#endif
-
-#ifdef PNG_READ_TRANSFORMS_SUPPORTED
-#ifdef PNG_READ_GAMMA_SUPPORTED
-/* In the case of gamma transformations only do transformations on images where
- * the [file] gamma and screen_gamma are not close reciprocals, otherwise it
- * slows things down slightly, and also needlessly introduces small errors.
- */
-static int /* PRIVATE */
-png_gamma_threshold(png_fixed_point screen_gamma, png_fixed_point file_gamma)
-{
-   /* PNG_GAMMA_THRESHOLD is the threshold for performing gamma
-    * correction as a difference of the overall transform from 1.0
-    *
-    * We want to compare the threshold with s*f - 1, if we get
-    * overflow here it is because of wacky gamma values so we
-    * turn on processing anyway.
-    */
-   png_fixed_point gtest;
-   return !png_muldiv(&gtest, screen_gamma, file_gamma, PNG_FP_1) ||
-       png_gamma_significant(gtest);
-}
-#endif
-
-/* Initialize everything needed for the read.  This includes modifying
- * the palette.
- */
-
-/*For the moment 'png_init_palette_transformations' and
- * 'png_init_rgb_transformations' only do some flag canceling optimizations.
- * The intent is that these two routines should have palette or rgb operations
- * extracted from 'png_init_read_transformations'.
- */
-static void /* PRIVATE */
-png_init_palette_transformations(png_structp png_ptr)
-{
-   /* Called to handle the (input) palette case.  In png_do_read_transformations
-    * the first step is to expand the palette if requested, so this code must
-    * take care to only make changes that are invariant with respect to the
-    * palette expansion, or only do them if there is no expansion.
-    *
-    * STRIP_ALPHA has already been handled in the caller (by setting num_trans
-    * to 0.)
-    */
-   int input_has_alpha = 0;
-   int input_has_transparency = 0;
-
-   if (png_ptr->num_trans > 0)
-   {
-      int i;
-
-      /* Ignore if all the entries are opaque (unlikely!) */
-      for (i=0; i<png_ptr->num_trans; ++i)
-         if (png_ptr->trans_alpha[i] == 255)
-            continue;
-         else if (png_ptr->trans_alpha[i] == 0)
-            input_has_transparency = 1;
-         else
-            input_has_alpha = 1;
-   }
-
-   /* If no alpha we can optimize. */
-   if (!input_has_alpha)
-   {
-      /* Any alpha means background and associative alpha processing is
-       * required, however if the alpha is 0 or 1 throughout OPTIIMIZE_ALPHA
-       * and ENCODE_ALPHA are irrelevant.
-       */
-      png_ptr->transformations &= ~PNG_ENCODE_ALPHA;
-      png_ptr->flags &= ~PNG_FLAG_OPTIMIZE_ALPHA;
-
-      if (!input_has_transparency)
-         png_ptr->transformations &= ~(PNG_COMPOSE | PNG_BACKGROUND_EXPAND);
-   }
-
-#if defined(PNG_READ_EXPAND_SUPPORTED) && defined(PNG_READ_BACKGROUND_SUPPORTED)
-   /* png_set_background handling - deals with the complexity of whether the
-    * background color is in the file format or the screen format in the case
-    * where an 'expand' will happen.
-    */
-
-   /* The following code cannot be entered in the alpha pre-multiplication case
-    * because PNG_BACKGROUND_EXPAND is cancelled below.
-    */
-   if ((png_ptr->transformations & PNG_BACKGROUND_EXPAND) &&
-       (png_ptr->transformations & PNG_EXPAND))
-   {
-      {
-         png_ptr->background.red   =
-             png_ptr->palette[png_ptr->background.index].red;
-         png_ptr->background.green =
-             png_ptr->palette[png_ptr->background.index].green;
-         png_ptr->background.blue  =
-             png_ptr->palette[png_ptr->background.index].blue;
-
-#ifdef PNG_READ_INVERT_ALPHA_SUPPORTED
-        if (png_ptr->transformations & PNG_INVERT_ALPHA)
-        {
-           if (!(png_ptr->transformations & PNG_EXPAND_tRNS))
-           {
-              /* Invert the alpha channel (in tRNS) unless the pixels are
-               * going to be expanded, in which case leave it for later
-               */
-              int i, istop = png_ptr->num_trans;
-
-              for (i=0; i<istop; i++)
-                 png_ptr->trans_alpha[i] = (png_byte)(255 -
-                    png_ptr->trans_alpha[i]);
-           }
-        }
-#endif /* PNG_READ_INVERT_ALPHA_SUPPORTED */
-      }
-   } /* background expand and (therefore) no alpha association. */
-#endif /* PNG_READ_EXPAND_SUPPORTED && PNG_READ_BACKGROUND_SUPPORTED */
-}
-
-static void /* PRIVATE */
-png_init_rgb_transformations(png_structp png_ptr)
-{
-   /* Added to libpng-1.5.4: check the color type to determine whether there
-    * is any alpha or transparency in the image and simply cancel the
-    * background and alpha mode stuff if there isn't.
-    */
-   int input_has_alpha = (png_ptr->color_type & PNG_COLOR_MASK_ALPHA) != 0;
-   int input_has_transparency = png_ptr->num_trans > 0;
-
-   /* If no alpha we can optimize. */
-   if (!input_has_alpha)
-   {
-      /* Any alpha means background and associative alpha processing is
-       * required, however if the alpha is 0 or 1 throughout OPTIIMIZE_ALPHA
-       * and ENCODE_ALPHA are irrelevant.
-       */
-#     ifdef PNG_READ_ALPHA_MODE_SUPPORTED
-         png_ptr->transformations &= ~PNG_ENCODE_ALPHA;
-         png_ptr->flags &= ~PNG_FLAG_OPTIMIZE_ALPHA;
-#     endif
-
-      if (!input_has_transparency)
-         png_ptr->transformations &= ~(PNG_COMPOSE | PNG_BACKGROUND_EXPAND);
-   }
-
-#if defined(PNG_READ_EXPAND_SUPPORTED) && defined(PNG_READ_BACKGROUND_SUPPORTED)
-   /* png_set_background handling - deals with the complexity of whether the
-    * background color is in the file format or the screen format in the case
-    * where an 'expand' will happen.
-    */
-
-   /* The following code cannot be entered in the alpha pre-multiplication case
-    * because PNG_BACKGROUND_EXPAND is cancelled below.
-    */
-   if ((png_ptr->transformations & PNG_BACKGROUND_EXPAND) &&
-       (png_ptr->transformations & PNG_EXPAND) &&
-       !(png_ptr->color_type & PNG_COLOR_MASK_COLOR))
-       /* i.e., GRAY or GRAY_ALPHA */
-   {
-      {
-         /* Expand background and tRNS chunks */
-         int gray = png_ptr->background.gray;
-         int trans_gray = png_ptr->trans_color.gray;
-
-         switch (png_ptr->bit_depth)
-         {
-            case 1:
-               gray *= 0xff;
-               trans_gray *= 0xff;
-               break;
-
-            case 2:
-               gray *= 0x55;
-               trans_gray *= 0x55;
-               break;
-
-            case 4:
-               gray *= 0x11;
-               trans_gray *= 0x11;
-               break;
-
-            default:
-
-            case 8:
-               /* Already 8 bits, fall through */
-
-            case 16:
-               /* Already a full 16 bits */
-               break;
-         }
-
-         png_ptr->background.red = png_ptr->background.green =
-            png_ptr->background.blue = (png_uint_16)gray;
-
-         if (!(png_ptr->transformations & PNG_EXPAND_tRNS))
-         {
-            png_ptr->trans_color.red = png_ptr->trans_color.green =
-               png_ptr->trans_color.blue = (png_uint_16)trans_gray;
-         }
-      }
-   } /* background expand and (therefore) no alpha association. */
-#endif /* PNG_READ_EXPAND_SUPPORTED && PNG_READ_BACKGROUND_SUPPORTED */
-}
-
-void /* PRIVATE */
-png_init_read_transformations(png_structp png_ptr)
-{
-   png_debug(1, "in png_init_read_transformations");
-
-   /* This internal function is called from png_read_start_row in pngrutil.c
-    * and it is called before the 'rowbytes' calculation is done, so the code
-    * in here can change or update the transformations flags.
-    *
-    * First do updates that do not depend on the details of the PNG image data
-    * being processed.
-    */
-
-#ifdef PNG_READ_GAMMA_SUPPORTED
-   /* Prior to 1.5.4 these tests were performed from png_set_gamma, 1.5.4 adds
-    * png_set_alpha_mode and this is another source for a default file gamma so
-    * the test needs to be performed later - here.  In addition prior to 1.5.4
-    * the tests were repeated for the PALETTE color type here - this is no
-    * longer necessary (and doesn't seem to have been necessary before.)
-    */
-   {
-      /* The following temporary indicates if overall gamma correction is
-       * required.
-       */
-      int gamma_correction = 0;
-
-      if (png_ptr->gamma != 0) /* has been set */
-      {
-         if (png_ptr->screen_gamma != 0) /* screen set too */
-            gamma_correction = png_gamma_threshold(png_ptr->gamma,
-               png_ptr->screen_gamma);
-
-         else
-            /* Assume the output matches the input; a long time default behavior
-             * of libpng, although the standard has nothing to say about this.
-             */
-            png_ptr->screen_gamma = png_reciprocal(png_ptr->gamma);
-      }
-
-      else if (png_ptr->screen_gamma != 0)
-         /* The converse - assume the file matches the screen, note that this
-          * perhaps undesireable default can (from 1.5.4) be changed by calling
-          * png_set_alpha_mode (even if the alpha handling mode isn't required
-          * or isn't changed from the default.)
-          */
-         png_ptr->gamma = png_reciprocal(png_ptr->screen_gamma);
-
-      else /* neither are set */
-         /* Just in case the following prevents any processing - file and screen
-          * are both assumed to be linear and there is no way to introduce a
-          * third gamma value other than png_set_background with 'UNIQUE', and,
-          * prior to 1.5.4
-          */
-         png_ptr->screen_gamma = png_ptr->gamma = PNG_FP_1;
-
-      /* Now turn the gamma transformation on or off as appropriate.  Notice
-       * that PNG_GAMMA just refers to the file->screen correction.  Alpha
-       * composition may independently cause gamma correction because it needs
-       * linear data (e.g. if the file has a gAMA chunk but the screen gamma
-       * hasn't been specified.)  In any case this flag may get turned off in
-       * the code immediately below if the transform can be handled outside the
-       * row loop.
-       */
-      if (gamma_correction)
-         png_ptr->transformations |= PNG_GAMMA;
-
-      else
-         png_ptr->transformations &= ~PNG_GAMMA;
-   }
-#endif
-
-   /* Certain transformations have the effect of preventing other
-    * transformations that happen afterward in png_do_read_transformations,
-    * resolve the interdependencies here.  From the code of
-    * png_do_read_transformations the order is:
-    *
-    *  1) PNG_EXPAND (including PNG_EXPAND_tRNS)
-    *  2) PNG_STRIP_ALPHA (if no compose)
-    *  3) PNG_RGB_TO_GRAY
-    *  4) PNG_GRAY_TO_RGB iff !PNG_BACKGROUND_IS_GRAY
-    *  5) PNG_COMPOSE
-    *  6) PNG_GAMMA
-    *  7) PNG_STRIP_ALPHA (if compose)
-    *  8) PNG_ENCODE_ALPHA
-    *  9) PNG_SCALE_16_TO_8
-    * 10) PNG_16_TO_8
-    * 11) PNG_QUANTIZE (converts to palette)
-    * 12) PNG_EXPAND_16
-    * 13) PNG_GRAY_TO_RGB iff PNG_BACKGROUND_IS_GRAY
-    * 14) PNG_INVERT_MONO
-    * 15) PNG_SHIFT
-    * 16) PNG_PACK
-    * 17) PNG_BGR
-    * 18) PNG_PACKSWAP
-    * 19) PNG_FILLER (includes PNG_ADD_ALPHA)
-    * 20) PNG_INVERT_ALPHA
-    * 21) PNG_SWAP_ALPHA
-    * 22) PNG_SWAP_BYTES
-    * 23) PNG_USER_TRANSFORM [must be last]
-    */
-#ifdef PNG_READ_STRIP_ALPHA_SUPPORTED
-   if ((png_ptr->transformations & PNG_STRIP_ALPHA) &&
-      !(png_ptr->transformations & PNG_COMPOSE))
-   {
-      /* Stripping the alpha channel happens immediately after the 'expand'
-       * transformations, before all other transformation, so it cancels out
-       * the alpha handling.  It has the side effect negating the effect of
-       * PNG_EXPAND_tRNS too:
-       */
-      png_ptr->transformations &= ~(PNG_BACKGROUND_EXPAND | PNG_ENCODE_ALPHA |
-         PNG_EXPAND_tRNS);
-      png_ptr->flags &= ~PNG_FLAG_OPTIMIZE_ALPHA;
-
-      /* Kill the tRNS chunk itself too.  Prior to 1.5.4 this did not happen
-       * so transparency information would remain just so long as it wasn't
-       * expanded.  This produces unexpected API changes if the set of things
-       * that do PNG_EXPAND_tRNS changes (perfectly possible given the
-       * documentation - which says ask for what you want, accept what you
-       * get.)  This makes the behavior consistent from 1.5.4:
-       */
-      png_ptr->num_trans = 0;
-   }
-#endif /* STRIP_ALPHA supported, no COMPOSE */
-
-#ifdef PNG_READ_ALPHA_MODE_SUPPORTED
-   /* If the screen gamma is about 1.0 then the OPTIMIZE_ALPHA and ENCODE_ALPHA
-    * settings will have no effect.
-    */
-   if (!png_gamma_significant(png_ptr->screen_gamma))
-   {
-      png_ptr->transformations &= ~PNG_ENCODE_ALPHA;
-      png_ptr->flags &= ~PNG_FLAG_OPTIMIZE_ALPHA;
-   }
-#endif
-
-#if defined(PNG_READ_EXPAND_SUPPORTED) && \
-   defined(PNG_READ_BACKGROUND_SUPPORTED) && \
-   defined(PNG_READ_GRAY_TO_RGB_SUPPORTED)
-   /* Detect gray background and attempt to enable optimization for
-    * gray --> RGB case.
-    *
-    * Note:  if PNG_BACKGROUND_EXPAND is set and color_type is either RGB or
-    * RGB_ALPHA (in which case need_expand is superfluous anyway), the
-    * background color might actually be gray yet not be flagged as such.
-    * This is not a problem for the current code, which uses
-    * PNG_BACKGROUND_IS_GRAY only to decide when to do the
-    * png_do_gray_to_rgb() transformation.
-    *
-    * TODO: this code needs to be revised to avoid the complexity and
-    * interdependencies.  The color type of the background should be recorded in
-    * png_set_background, along with the bit depth, then the code has a record
-    * of exactly what color space the background is currently in.
-    */
-   if (png_ptr->transformations & PNG_BACKGROUND_EXPAND)
-   {
-      /* PNG_BACKGROUND_EXPAND: the background is in the file color space, so if
-       * the file was grayscale the background value is gray.
-       */
-      if (!(png_ptr->color_type & PNG_COLOR_MASK_COLOR))
-         png_ptr->mode |= PNG_BACKGROUND_IS_GRAY;
-   }
-
-   else if (png_ptr->transformations & PNG_COMPOSE)
-   {
-      /* PNG_COMPOSE: png_set_background was called with need_expand false,
-       * so the color is in the color space of the output or png_set_alpha_mode
-       * was called and the color is black.  Ignore RGB_TO_GRAY because that
-       * happens before GRAY_TO_RGB.
-       */
-      if (png_ptr->transformations & PNG_GRAY_TO_RGB)
-      {
-         if (png_ptr->background.red == png_ptr->background.green &&
-             png_ptr->background.red == png_ptr->background.blue)
-         {
-            png_ptr->mode |= PNG_BACKGROUND_IS_GRAY;
-            png_ptr->background.gray = png_ptr->background.red;
-         }
-      }
-   }
-#endif /* PNG_READ_GRAY_TO_RGB_SUPPORTED (etc) */
-
-   /* For indexed PNG data (PNG_COLOR_TYPE_PALETTE) many of the transformations
-    * can be performed directly on the palette, and some (such as rgb to gray)
-    * can be optimized inside the palette.  This is particularly true of the
-    * composite (background and alpha) stuff, which can be pretty much all done
-    * in the palette even if the result is expanded to RGB or gray afterward.
-    *
-    * NOTE: this is Not Yet Implemented, the code behaves as in 1.5.1 and
-    * earlier and the palette stuff is actually handled on the first row.  This
-    * leads to the reported bug that the palette returned by png_get_PLTE is not
-    * updated.
-    */
-   if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE)
-      png_init_palette_transformations(png_ptr);
-
-   else
-      png_init_rgb_transformations(png_ptr);
-
-#if defined(PNG_READ_BACKGROUND_SUPPORTED) && \
-   defined(PNG_READ_EXPAND_16_SUPPORTED)
-   if ((png_ptr->transformations & PNG_EXPAND_16) &&
-      (png_ptr->transformations & PNG_COMPOSE) &&
-      !(png_ptr->transformations & PNG_BACKGROUND_EXPAND) &&
-      png_ptr->bit_depth != 16)
-   {
-      /* TODO: fix this.  Because the expand_16 operation is after the compose
-       * handling the background color must be 8, not 16, bits deep, but the
-       * application will supply a 16-bit value so reduce it here.
-       *
-       * The PNG_BACKGROUND_EXPAND code above does not expand to 16 bits at
-       * present, so that case is ok (until do_expand_16 is moved.)
-       *
-       * NOTE: this discards the low 16 bits of the user supplied background
-       * color, but until expand_16 works properly there is no choice!
-       */
-#     define CHOP(x) (x)=((png_uint_16)(((png_uint_32)(x)*255+32895) >> 16))
-      CHOP(png_ptr->background.red);
-      CHOP(png_ptr->background.green);
-      CHOP(png_ptr->background.blue);
-      CHOP(png_ptr->background.gray);
-#     undef CHOP
-   }
-#endif /* PNG_READ_BACKGROUND_SUPPORTED && PNG_READ_EXPAND_16_SUPPORTED */
-
-#if defined(PNG_READ_BACKGROUND_SUPPORTED) && \
-   (defined(PNG_READ_SCALE_16_TO_8_SUPPORTED) || \
-   defined(PNG_READ_STRIP_16_TO_8_SUPPORTED))
-   if ((png_ptr->transformations & (PNG_16_TO_8|PNG_SCALE_16_TO_8)) &&
-      (png_ptr->transformations & PNG_COMPOSE) &&
-      !(png_ptr->transformations & PNG_BACKGROUND_EXPAND) &&
-      png_ptr->bit_depth == 16)
-   {
-      /* On the other hand, if a 16-bit file is to be reduced to 8-bits per
-       * component this will also happen after PNG_COMPOSE and so the background
-       * color must be pre-expanded here.
-       *
-       * TODO: fix this too.
-       */
-      png_ptr->background.red = (png_uint_16)(png_ptr->background.red * 257);
-      png_ptr->background.green =
-         (png_uint_16)(png_ptr->background.green * 257);
-      png_ptr->background.blue = (png_uint_16)(png_ptr->background.blue * 257);
-      png_ptr->background.gray = (png_uint_16)(png_ptr->background.gray * 257);
-   }
-#endif
-
-   /* NOTE: below 'PNG_READ_ALPHA_MODE_SUPPORTED' is presumed to also enable the
-    * background support (see the comments in scripts/pnglibconf.dfa), this
-    * allows pre-multiplication of the alpha channel to be implemented as
-    * compositing on black.  This is probably sub-optimal and has been done in
-    * 1.5.4 betas simply to enable external critique and testing (i.e. to
-    * implement the new API quickly, without lots of internal changes.)
-    */
-
-#ifdef PNG_READ_GAMMA_SUPPORTED
-#  ifdef PNG_READ_BACKGROUND_SUPPORTED
-      /* Includes ALPHA_MODE */
-      png_ptr->background_1 = png_ptr->background;
-#  endif
-
-   /* This needs to change - in the palette image case a whole set of tables are
-    * built when it would be quicker to just calculate the correct value for
-    * each palette entry directly.  Also, the test is too tricky - why check
-    * PNG_RGB_TO_GRAY if PNG_GAMMA is not set?  The answer seems to be that
-    * PNG_GAMMA is cancelled even if the gamma is known?  The test excludes the
-    * PNG_COMPOSE case, so apparently if there is no *overall* gamma correction
-    * the gamma tables will not be built even if composition is required on a
-    * gamma encoded value.
-    *
-    * In 1.5.4 this is addressed below by an additional check on the individual
-    * file gamma - if it is not 1.0 both RGB_TO_GRAY and COMPOSE need the
-    * tables.
-    */
-   if ((png_ptr->transformations & PNG_GAMMA)
-      || ((png_ptr->transformations & PNG_RGB_TO_GRAY)
-         && (png_gamma_significant(png_ptr->gamma) ||
-            png_gamma_significant(png_ptr->screen_gamma)))
-      || ((png_ptr->transformations & PNG_COMPOSE)
-         && (png_gamma_significant(png_ptr->gamma)
-            || png_gamma_significant(png_ptr->screen_gamma)
-#  ifdef PNG_READ_BACKGROUND_SUPPORTED
-            || (png_ptr->background_gamma_type == PNG_BACKGROUND_GAMMA_UNIQUE
-               && png_gamma_significant(png_ptr->background_gamma))
-#  endif
-      )) || ((png_ptr->transformations & PNG_ENCODE_ALPHA)
-         && png_gamma_significant(png_ptr->screen_gamma))
-      )
-   {
-      png_build_gamma_table(png_ptr, png_ptr->bit_depth);
-
-#ifdef PNG_READ_BACKGROUND_SUPPORTED
-      if (png_ptr->transformations & PNG_COMPOSE)
-      {
-         /* Issue a warning about this combination: because RGB_TO_GRAY is
-          * optimized to do the gamma transform if present yet do_background has
-          * to do the same thing if both options are set a
-          * double-gamma-correction happens.  This is true in all versions of
-          * libpng to date.
-          */
-         if (png_ptr->transformations & PNG_RGB_TO_GRAY)
-            png_warning(png_ptr,
-               "libpng does not support gamma+background+rgb_to_gray");
-
-         if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE)
-         {
-            /* We don't get to here unless there is a tRNS chunk with non-opaque
-             * entries - see the checking code at the start of this function.
-             */
-            png_color back, back_1;
-            png_colorp palette = png_ptr->palette;
-            int num_palette = png_ptr->num_palette;
-            int i;
-            if (png_ptr->background_gamma_type == PNG_BACKGROUND_GAMMA_FILE)
-            {
-
-               back.red = png_ptr->gamma_table[png_ptr->background.red];
-               back.green = png_ptr->gamma_table[png_ptr->background.green];
-               back.blue = png_ptr->gamma_table[png_ptr->background.blue];
-
-               back_1.red = png_ptr->gamma_to_1[png_ptr->background.red];
-               back_1.green = png_ptr->gamma_to_1[png_ptr->background.green];
-               back_1.blue = png_ptr->gamma_to_1[png_ptr->background.blue];
-            }
-            else
-            {
-               png_fixed_point g, gs;
-
-               switch (png_ptr->background_gamma_type)
-               {
-                  case PNG_BACKGROUND_GAMMA_SCREEN:
-                     g = (png_ptr->screen_gamma);
-                     gs = PNG_FP_1;
-                     break;
-
-                  case PNG_BACKGROUND_GAMMA_FILE:
-                     g = png_reciprocal(png_ptr->gamma);
-                     gs = png_reciprocal2(png_ptr->gamma,
-                        png_ptr->screen_gamma);
-                     break;
-
-                  case PNG_BACKGROUND_GAMMA_UNIQUE:
-                     g = png_reciprocal(png_ptr->background_gamma);
-                     gs = png_reciprocal2(png_ptr->background_gamma,
-                        png_ptr->screen_gamma);
-                     break;
-                  default:
-                     g = PNG_FP_1;    /* back_1 */
-                     gs = PNG_FP_1;   /* back */
-                     break;
-               }
-
-               if (png_gamma_significant(gs))
-               {
-                  back.red = png_gamma_8bit_correct(png_ptr->background.red,
-                      gs);
-                  back.green = png_gamma_8bit_correct(png_ptr->background.green,
-                      gs);
-                  back.blue = png_gamma_8bit_correct(png_ptr->background.blue,
-                      gs);
-               }
-
-               else
-               {
-                  back.red   = (png_byte)png_ptr->background.red;
-                  back.green = (png_byte)png_ptr->background.green;
-                  back.blue  = (png_byte)png_ptr->background.blue;
-               }
-
-               if (png_gamma_significant(g))
-               {
-                  back_1.red = png_gamma_8bit_correct(png_ptr->background.red,
-                     g);
-                  back_1.green = png_gamma_8bit_correct(
-                     png_ptr->background.green, g);
-                  back_1.blue = png_gamma_8bit_correct(png_ptr->background.blue,
-                     g);
-               }
-
-               else
-               {
-                  back_1.red   = (png_byte)png_ptr->background.red;
-                  back_1.green = (png_byte)png_ptr->background.green;
-                  back_1.blue  = (png_byte)png_ptr->background.blue;
-               }
-            }
-
-            for (i = 0; i < num_palette; i++)
-            {
-               if (i < (int)png_ptr->num_trans &&
-                   png_ptr->trans_alpha[i] != 0xff)
-               {
-                  if (png_ptr->trans_alpha[i] == 0)
-                  {
-                     palette[i] = back;
-                  }
-                  else /* if (png_ptr->trans_alpha[i] != 0xff) */
-                  {
-                     png_byte v, w;
-
-                     v = png_ptr->gamma_to_1[palette[i].red];
-                     png_composite(w, v, png_ptr->trans_alpha[i], back_1.red);
-                     palette[i].red = png_ptr->gamma_from_1[w];
-
-                     v = png_ptr->gamma_to_1[palette[i].green];
-                     png_composite(w, v, png_ptr->trans_alpha[i], back_1.green);
-                     palette[i].green = png_ptr->gamma_from_1[w];
-
-                     v = png_ptr->gamma_to_1[palette[i].blue];
-                     png_composite(w, v, png_ptr->trans_alpha[i], back_1.blue);
-                     palette[i].blue = png_ptr->gamma_from_1[w];
-                  }
-               }
-               else
-               {
-                  palette[i].red = png_ptr->gamma_table[palette[i].red];
-                  palette[i].green = png_ptr->gamma_table[palette[i].green];
-                  palette[i].blue = png_ptr->gamma_table[palette[i].blue];
-               }
-            }
-
-            /* Prevent the transformations being done again.
-             *
-             * NOTE: this is highly dubious; it removes the transformations in
-             * place.  This seems inconsistent with the general treatment of the
-             * transformations elsewhere.
-             */
-            png_ptr->transformations &= ~(PNG_COMPOSE | PNG_GAMMA);
-         } /* color_type == PNG_COLOR_TYPE_PALETTE */
-
-         /* if (png_ptr->background_gamma_type!=PNG_BACKGROUND_GAMMA_UNKNOWN) */
-         else /* color_type != PNG_COLOR_TYPE_PALETTE */
-         {
-            int gs_sig, g_sig;
-            png_fixed_point g = PNG_FP_1;  /* Correction to linear */
-            png_fixed_point gs = PNG_FP_1; /* Correction to screen */
-
-            switch (png_ptr->background_gamma_type)
-            {
-               case PNG_BACKGROUND_GAMMA_SCREEN:
-                  g = png_ptr->screen_gamma;
-                  /* gs = PNG_FP_1; */
-                  break;
-
-               case PNG_BACKGROUND_GAMMA_FILE:
-                  g = png_reciprocal(png_ptr->gamma);
-                  gs = png_reciprocal2(png_ptr->gamma, png_ptr->screen_gamma);
-                  break;
-
-               case PNG_BACKGROUND_GAMMA_UNIQUE:
-                  g = png_reciprocal(png_ptr->background_gamma);
-                  gs = png_reciprocal2(png_ptr->background_gamma,
-                      png_ptr->screen_gamma);
-                  break;
-
-               default:
-                  dg_png_error(png_ptr, "invalid background gamma type");
-            }
-
-            g_sig = png_gamma_significant(g);
-            gs_sig = png_gamma_significant(gs);
-
-            if (g_sig)
-               png_ptr->background_1.gray = png_gamma_correct(png_ptr,
-                   png_ptr->background.gray, g);
-
-            if (gs_sig)
-               png_ptr->background.gray = png_gamma_correct(png_ptr,
-                   png_ptr->background.gray, gs);
-
-            if ((png_ptr->background.red != png_ptr->background.green) ||
-                (png_ptr->background.red != png_ptr->background.blue) ||
-                (png_ptr->background.red != png_ptr->background.gray))
-            {
-               /* RGB or RGBA with color background */
-               if (g_sig)
-               {
-                  png_ptr->background_1.red = png_gamma_correct(png_ptr,
-                      png_ptr->background.red, g);
-
-                  png_ptr->background_1.green = png_gamma_correct(png_ptr,
-                      png_ptr->background.green, g);
-
-                  png_ptr->background_1.blue = png_gamma_correct(png_ptr,
-                      png_ptr->background.blue, g);
-               }
-
-               if (gs_sig)
-               {
-                  png_ptr->background.red = png_gamma_correct(png_ptr,
-                      png_ptr->background.red, gs);
-
-                  png_ptr->background.green = png_gamma_correct(png_ptr,
-                      png_ptr->background.green, gs);
-
-                  png_ptr->background.blue = png_gamma_correct(png_ptr,
-                      png_ptr->background.blue, gs);
-               }
-            }
-
-            else
-            {
-               /* GRAY, GRAY ALPHA, RGB, or RGBA with gray background */
-               png_ptr->background_1.red = png_ptr->background_1.green
-                   = png_ptr->background_1.blue = png_ptr->background_1.gray;
-
-               png_ptr->background.red = png_ptr->background.green
-                   = png_ptr->background.blue = png_ptr->background.gray;
-            }
-
-            /* The background is now in screen gamma: */
-            png_ptr->background_gamma_type = PNG_BACKGROUND_GAMMA_SCREEN;
-         } /* color_type != PNG_COLOR_TYPE_PALETTE */
-      }/* png_ptr->transformations & PNG_BACKGROUND */
-
-      else
-      /* Transformation does not include PNG_BACKGROUND */
-#endif /* PNG_READ_BACKGROUND_SUPPORTED */
-      if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE
-#ifdef PNG_READ_RGB_TO_GRAY_SUPPORTED
-         /* RGB_TO_GRAY needs to have non-gamma-corrected values! */
-         && ((png_ptr->transformations & PNG_EXPAND) == 0 ||
-         (png_ptr->transformations & PNG_RGB_TO_GRAY) == 0)
-#endif
-         )
-      {
-         png_colorp palette = png_ptr->palette;
-         int num_palette = png_ptr->num_palette;
-         int i;
-
-         /* NOTE: there are other transformations that should probably be in
-          * here too.
-          */
-         for (i = 0; i < num_palette; i++)
-         {
-            palette[i].red = png_ptr->gamma_table[palette[i].red];
-            palette[i].green = png_ptr->gamma_table[palette[i].green];
-            palette[i].blue = png_ptr->gamma_table[palette[i].blue];
-         }
-
-         /* Done the gamma correction. */
-         png_ptr->transformations &= ~PNG_GAMMA;
-      } /* color_type == PALETTE && !PNG_BACKGROUND transformation */
-   }
-#ifdef PNG_READ_BACKGROUND_SUPPORTED
-   else
-#endif
-#endif /* PNG_READ_GAMMA_SUPPORTED */
-
-#ifdef PNG_READ_BACKGROUND_SUPPORTED
-   /* No GAMMA transformation (see the hanging else 4 lines above) */
-   if ((png_ptr->transformations & PNG_COMPOSE) &&
-       (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE))
-   {
-      int i;
-      int istop = (int)png_ptr->num_trans;
-      png_color back;
-      png_colorp palette = png_ptr->palette;
-
-      back.red   = (png_byte)png_ptr->background.red;
-      back.green = (png_byte)png_ptr->background.green;
-      back.blue  = (png_byte)png_ptr->background.blue;
-
-      for (i = 0; i < istop; i++)
-      {
-         if (png_ptr->trans_alpha[i] == 0)
-         {
-            palette[i] = back;
-         }
-
-         else if (png_ptr->trans_alpha[i] != 0xff)
-         {
-            /* The png_composite() macro is defined in png.h */
-            png_composite(palette[i].red, palette[i].red,
-                png_ptr->trans_alpha[i], back.red);
-
-            png_composite(palette[i].green, palette[i].green,
-                png_ptr->trans_alpha[i], back.green);
-
-            png_composite(palette[i].blue, palette[i].blue,
-                png_ptr->trans_alpha[i], back.blue);
-         }
-      }
-
-      png_ptr->transformations &= ~PNG_COMPOSE;
-   }
-#endif /* PNG_READ_BACKGROUND_SUPPORTED */
-
-#ifdef PNG_READ_SHIFT_SUPPORTED
-   if ((png_ptr->transformations & PNG_SHIFT) &&
-      !(png_ptr->transformations & PNG_EXPAND) &&
-       (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE))
-   {
-      int i;
-      int istop = png_ptr->num_palette;
-      int shift = 8 - png_ptr->sig_bit.red;
-
-      png_ptr->transformations &= ~PNG_SHIFT;
-
-      /* significant bits can be in the range 1 to 7 for a meaninful result, if
-       * the number of significant bits is 0 then no shift is done (this is an
-       * error condition which is silently ignored.)
-       */
-      if (shift > 0 && shift < 8) for (i=0; i<istop; ++i)
-      {
-         int component = png_ptr->palette[i].red;
-
-         component >>= shift;
-         png_ptr->palette[i].red = (png_byte)component;
-      }
-
-      shift = 8 - png_ptr->sig_bit.green;
-      if (shift > 0 && shift < 8) for (i=0; i<istop; ++i)
-      {
-         int component = png_ptr->palette[i].green;
-
-         component >>= shift;
-         png_ptr->palette[i].green = (png_byte)component;
-      }
-
-      shift = 8 - png_ptr->sig_bit.blue;
-      if (shift > 0 && shift < 8) for (i=0; i<istop; ++i)
-      {
-         int component = png_ptr->palette[i].blue;
-
-         component >>= shift;
-         png_ptr->palette[i].blue = (png_byte)component;
-      }
-   }
-#endif  /* PNG_READ_SHIFT_SUPPORTED */
-}
-
-/* Modify the info structure to reflect the transformations.  The
- * info should be updated so a PNG file could be written with it,
- * assuming the transformations result in valid PNG data.
- */
-void /* PRIVATE */
-png_read_transform_info(png_structp png_ptr, png_infop info_ptr)
-{
-   png_debug(1, "in png_read_transform_info");
-
-#ifdef PNG_READ_EXPAND_SUPPORTED
-   if (png_ptr->transformations & PNG_EXPAND)
-   {
-      if (info_ptr->color_type == PNG_COLOR_TYPE_PALETTE)
-      {
-         /* This check must match what actually happens in
-          * png_do_expand_palette; if it ever checks the tRNS chunk to see if
-          * it is all opaque we must do the same (at present it does not.)
-          */
-         if (png_ptr->num_trans > 0)
-            info_ptr->color_type = PNG_COLOR_TYPE_RGB_ALPHA;
-
-         else
-            info_ptr->color_type = PNG_COLOR_TYPE_RGB;
-
-         info_ptr->bit_depth = 8;
-         info_ptr->num_trans = 0;
-      }
-      else
-      {
-         if (png_ptr->num_trans)
-         {
-            if (png_ptr->transformations & PNG_EXPAND_tRNS)
-               info_ptr->color_type |= PNG_COLOR_MASK_ALPHA;
-         }
-         if (info_ptr->bit_depth < 8)
-            info_ptr->bit_depth = 8;
-
-         info_ptr->num_trans = 0;
-      }
-   }
-#endif
-
-#if defined(PNG_READ_BACKGROUND_SUPPORTED) ||\
-   defined(PNG_READ_ALPHA_MODE_SUPPORTED)
-   /* The following is almost certainly wrong unless the background value is in
-    * the screen space!
-    */
-   if (png_ptr->transformations & PNG_COMPOSE)
-      info_ptr->background = png_ptr->background;
-#endif
-
-#ifdef PNG_READ_GAMMA_SUPPORTED
-   /* The following used to be conditional on PNG_GAMMA (prior to 1.5.4),
-    * however it seems that the code in png_init_read_transformations, which has
-    * been called before this from png_read_update_info->png_read_start_row
-    * sometimes does the gamma transform and cancels the flag.
-    */
-   info_ptr->gamma = png_ptr->gamma;
-#endif
-
-   if (info_ptr->bit_depth == 16)
-   {
-#  ifdef PNG_READ_16BIT_SUPPORTED
-#     ifdef PNG_READ_SCALE_16_TO_8_SUPPORTED
-         if (png_ptr->transformations & PNG_SCALE_16_TO_8)
-            info_ptr->bit_depth = 8;
-#     endif
-
-#     ifdef PNG_READ_STRIP_16_TO_8_SUPPORTED
-         if (png_ptr->transformations & PNG_16_TO_8)
-            info_ptr->bit_depth = 8;
-#     endif
-
-#  else
-      /* No 16 bit support: force chopping 16-bit input down to 8, in this case
-       * the app program can chose if both APIs are available by setting the
-       * correct scaling to use.
-       */
-#     ifdef PNG_READ_STRIP_16_TO_8_SUPPORTED
-         /* For compatibility with previous versions use the strip method by
-          * default.  This code works because if PNG_SCALE_16_TO_8 is already
-          * set the code below will do that in preference to the chop.
-          */
-         png_ptr->transformations |= PNG_16_TO_8;
-         info_ptr->bit_depth = 8;
-#     else
-
-#        ifdef PNG_READ_SCALE_16_TO_8_SUPPORTED
-            png_ptr->transformations |= PNG_SCALE_16_TO_8;
-            info_ptr->bit_depth = 8;
-#        else
-
-            CONFIGURATION ERROR: you must enable at least one 16 to 8 method
-#        endif
-#    endif
-#endif /* !READ_16BIT_SUPPORTED */
-   }
-
-#ifdef PNG_READ_GRAY_TO_RGB_SUPPORTED
-   if (png_ptr->transformations & PNG_GRAY_TO_RGB)
-      info_ptr->color_type = (png_byte)(info_ptr->color_type |
-         PNG_COLOR_MASK_COLOR);
-#endif
-
-#ifdef PNG_READ_RGB_TO_GRAY_SUPPORTED
-   if (png_ptr->transformations & PNG_RGB_TO_GRAY)
-      info_ptr->color_type = (png_byte)(info_ptr->color_type &
-         ~PNG_COLOR_MASK_COLOR);
-#endif
-
-#ifdef PNG_READ_QUANTIZE_SUPPORTED
-   if (png_ptr->transformations & PNG_QUANTIZE)
-   {
-      if (((info_ptr->color_type == PNG_COLOR_TYPE_RGB) ||
-          (info_ptr->color_type == PNG_COLOR_TYPE_RGB_ALPHA)) &&
-          png_ptr->palette_lookup && info_ptr->bit_depth == 8)
-      {
-         info_ptr->color_type = PNG_COLOR_TYPE_PALETTE;
-      }
-   }
-#endif
-
-#ifdef PNG_READ_EXPAND_16_SUPPORTED
-   if (png_ptr->transformations & PNG_EXPAND_16 && info_ptr->bit_depth == 8 &&
-      info_ptr->color_type != PNG_COLOR_TYPE_PALETTE)
-   {
-      info_ptr->bit_depth = 16;
-   }
-#endif
-
-#ifdef PNG_READ_PACK_SUPPORTED
-   if ((png_ptr->transformations & PNG_PACK) && (info_ptr->bit_depth < 8))
-      info_ptr->bit_depth = 8;
-#endif
-
-   if (info_ptr->color_type == PNG_COLOR_TYPE_PALETTE)
-      info_ptr->channels = 1;
-
-   else if (info_ptr->color_type & PNG_COLOR_MASK_COLOR)
-      info_ptr->channels = 3;
-
-   else
-      info_ptr->channels = 1;
-
-#ifdef PNG_READ_STRIP_ALPHA_SUPPORTED
-   if (png_ptr->transformations & PNG_STRIP_ALPHA)
-   {
-      info_ptr->color_type = (png_byte)(info_ptr->color_type &
-         ~PNG_COLOR_MASK_ALPHA);
-      info_ptr->num_trans = 0;
-   }
-#endif
-
-   if (info_ptr->color_type & PNG_COLOR_MASK_ALPHA)
-      info_ptr->channels++;
-
-#ifdef PNG_READ_FILLER_SUPPORTED
-   /* STRIP_ALPHA and FILLER allowed:  MASK_ALPHA bit stripped above */
-   if ((png_ptr->transformations & PNG_FILLER) &&
-       ((info_ptr->color_type == PNG_COLOR_TYPE_RGB) ||
-       (info_ptr->color_type == PNG_COLOR_TYPE_GRAY)))
-   {
-      info_ptr->channels++;
-      /* If adding a true alpha channel not just filler */
-      if (png_ptr->transformations & PNG_ADD_ALPHA)
-         info_ptr->color_type |= PNG_COLOR_MASK_ALPHA;
-   }
-#endif
-
-#if defined(PNG_USER_TRANSFORM_PTR_SUPPORTED) && \
-defined(PNG_READ_USER_TRANSFORM_SUPPORTED)
-   if (png_ptr->transformations & PNG_USER_TRANSFORM)
-   {
-      if (info_ptr->bit_depth < png_ptr->user_transform_depth)
-         info_ptr->bit_depth = png_ptr->user_transform_depth;
-
-      if (info_ptr->channels < png_ptr->user_transform_channels)
-         info_ptr->channels = png_ptr->user_transform_channels;
-   }
-#endif
-
-   info_ptr->pixel_depth = (png_byte)(info_ptr->channels *
-       info_ptr->bit_depth);
-
-   info_ptr->rowbytes = PNG_ROWBYTES(info_ptr->pixel_depth, info_ptr->width);
-
-   /* Adding in 1.5.4: cache the above value in png_struct so that we can later
-    * check in png_rowbytes that the user buffer won't get overwritten.  Note
-    * that the field is not always set - if png_read_update_info isn't called
-    * the application has to either not do any transforms or get the calculation
-    * right itself.
-    */
-   png_ptr->info_rowbytes = info_ptr->rowbytes;
-
-#ifndef PNG_READ_EXPAND_SUPPORTED
-   if (png_ptr)
-      return;
-#endif
-}
-
-/* Transform the row.  The order of transformations is significant,
- * and is very touchy.  If you add a transformation, take care to
- * decide how it fits in with the other transformations here.
- */
-void /* PRIVATE */
-png_do_read_transformations(png_structp png_ptr, png_row_infop row_info)
-{
-   png_debug(1, "in png_do_read_transformations");
-
-   if (png_ptr->row_buf == NULL)
-   {
-      /* Prior to 1.5.4 this output row/pass where the NULL pointer is, but this
-       * error is incredibly rare and incredibly easy to debug without this
-       * information.
-       */
-      dg_png_error(png_ptr, "NULL row buffer");
-   }
-
-   /* The following is debugging; prior to 1.5.4 the code was never compiled in;
-    * in 1.5.4 PNG_FLAG_DETECT_UNINITIALIZED was added and the macro
-    * PNG_WARN_UNINITIALIZED_ROW removed.  In 1.5 the new flag is set only for
-    * selected new APIs to ensure that there is no API change.
-    */
-   if ((png_ptr->flags & PNG_FLAG_DETECT_UNINITIALIZED) != 0 &&
-      !(png_ptr->flags & PNG_FLAG_ROW_INIT))
-   {
-      /* Application has failed to call either png_read_start_image() or
-       * png_read_update_info() after setting transforms that expand pixels.
-       * This check added to libpng-1.2.19 (but not enabled until 1.5.4).
-       */
-      dg_png_error(png_ptr, "Uninitialized row");
-   }
-
-#ifdef PNG_READ_EXPAND_SUPPORTED
-   if (png_ptr->transformations & PNG_EXPAND)
-   {
-      if (row_info->color_type == PNG_COLOR_TYPE_PALETTE)
-      {
-         png_do_expand_palette(row_info, png_ptr->row_buf + 1,
-             png_ptr->palette, png_ptr->trans_alpha, png_ptr->num_trans);
-      }
-
-      else
-      {
-         if (png_ptr->num_trans &&
-             (png_ptr->transformations & PNG_EXPAND_tRNS))
-            png_do_expand(row_info, png_ptr->row_buf + 1,
-                &(png_ptr->trans_color));
-
-         else
-            png_do_expand(row_info, png_ptr->row_buf + 1,
-                NULL);
-      }
-   }
-#endif
-
-#ifdef PNG_READ_STRIP_ALPHA_SUPPORTED
-   if ((png_ptr->transformations & PNG_STRIP_ALPHA) &&
-      !(png_ptr->transformations & PNG_COMPOSE) &&
-      (row_info->color_type == PNG_COLOR_TYPE_RGB_ALPHA ||
-      row_info->color_type == PNG_COLOR_TYPE_GRAY_ALPHA))
-      png_do_strip_channel(row_info, png_ptr->row_buf + 1,
-         0 /* at_start == false, because SWAP_ALPHA happens later */);
-#endif
-
-#ifdef PNG_READ_RGB_TO_GRAY_SUPPORTED
-   if (png_ptr->transformations & PNG_RGB_TO_GRAY)
-   {
-      int rgb_error =
-          png_do_rgb_to_gray(png_ptr, row_info,
-              png_ptr->row_buf + 1);
-
-      if (rgb_error)
-      {
-         png_ptr->rgb_to_gray_status=1;
-         if ((png_ptr->transformations & PNG_RGB_TO_GRAY) ==
-             PNG_RGB_TO_GRAY_WARN)
-            png_warning(png_ptr, "png_do_rgb_to_gray found nongray pixel");
-
-         if ((png_ptr->transformations & PNG_RGB_TO_GRAY) ==
-             PNG_RGB_TO_GRAY_ERR)
-            dg_png_error(png_ptr, "png_do_rgb_to_gray found nongray pixel");
-      }
-   }
-#endif
-
-/* From Andreas Dilger e-mail to png-implement, 26 March 1998:
- *
- *   In most cases, the "simple transparency" should be done prior to doing
- *   gray-to-RGB, or you will have to test 3x as many bytes to check if a
- *   pixel is transparent.  You would also need to make sure that the
- *   transparency information is upgraded to RGB.
- *
- *   To summarize, the current flow is:
- *   - Gray + simple transparency -> compare 1 or 2 gray bytes and composite
- *                                   with background "in place" if transparent,
- *                                   convert to RGB if necessary
- *   - Gray + alpha -> composite with gray background and remove alpha bytes,
- *                                   convert to RGB if necessary
- *
- *   To support RGB backgrounds for gray images we need:
- *   - Gray + simple transparency -> convert to RGB + simple transparency,
- *                                   compare 3 or 6 bytes and composite with
- *                                   background "in place" if transparent
- *                                   (3x compare/pixel compared to doing
- *                                   composite with gray bkgrnd)
- *   - Gray + alpha -> convert to RGB + alpha, composite with background and
- *                                   remove alpha bytes (3x float
- *                                   operations/pixel compared with composite
- *                                   on gray background)
- *
- *  Greg's change will do this.  The reason it wasn't done before is for
- *  performance, as this increases the per-pixel operations.  If we would check
- *  in advance if the background was gray or RGB, and position the gray-to-RGB
- *  transform appropriately, then it would save a lot of work/time.
- */
-
-#ifdef PNG_READ_GRAY_TO_RGB_SUPPORTED
-   /* If gray -> RGB, do so now only if background is non-gray; else do later
-    * for performance reasons
-    */
-   if ((png_ptr->transformations & PNG_GRAY_TO_RGB) &&
-       !(png_ptr->mode & PNG_BACKGROUND_IS_GRAY))
-      png_do_gray_to_rgb(row_info, png_ptr->row_buf + 1);
-#endif
-
-#if (defined PNG_READ_BACKGROUND_SUPPORTED) ||\
-   (defined PNG_READ_ALPHA_MODE_SUPPORTED)
-   if (png_ptr->transformations & PNG_COMPOSE)
-      png_do_compose(row_info, png_ptr->row_buf + 1, png_ptr);
-#endif
-
-#ifdef PNG_READ_GAMMA_SUPPORTED
-   if ((png_ptr->transformations & PNG_GAMMA) &&
-#ifdef PNG_READ_RGB_TO_GRAY_SUPPORTED
-      /* Because RGB_TO_GRAY does the gamma transform. */
-      !(png_ptr->transformations & PNG_RGB_TO_GRAY) &&
-#endif
-#if (defined PNG_READ_BACKGROUND_SUPPORTED) ||\
-   (defined PNG_READ_ALPHA_MODE_SUPPORTED)
-      /* Because PNG_COMPOSE does the gamma transform if there is something to
-       * do (if there is an alpha channel or transparency.)
-       */
-       !((png_ptr->transformations & PNG_COMPOSE) &&
-       ((png_ptr->num_trans != 0) ||
-       (png_ptr->color_type & PNG_COLOR_MASK_ALPHA))) &&
-#endif
-      /* Because png_init_read_transformations transforms the palette, unless
-       * RGB_TO_GRAY will do the transform.
-       */
-       (png_ptr->color_type != PNG_COLOR_TYPE_PALETTE))
-      png_do_gamma(row_info, png_ptr->row_buf + 1, png_ptr);
-#endif
-
-#ifdef PNG_READ_STRIP_ALPHA_SUPPORTED
-   if ((png_ptr->transformations & PNG_STRIP_ALPHA) &&
-      (png_ptr->transformations & PNG_COMPOSE) &&
-      (row_info->color_type == PNG_COLOR_TYPE_RGB_ALPHA ||
-      row_info->color_type == PNG_COLOR_TYPE_GRAY_ALPHA))
-      png_do_strip_channel(row_info, png_ptr->row_buf + 1,
-         0 /* at_start == false, because SWAP_ALPHA happens later */);
-#endif
-
-#ifdef PNG_READ_ALPHA_MODE_SUPPORTED
-   if ((png_ptr->transformations & PNG_ENCODE_ALPHA) &&
-      (row_info->color_type & PNG_COLOR_MASK_ALPHA))
-      png_do_encode_alpha(row_info, png_ptr->row_buf + 1, png_ptr);
-#endif
-
-#ifdef PNG_READ_SCALE_16_TO_8_SUPPORTED
-   if (png_ptr->transformations & PNG_SCALE_16_TO_8)
-      png_do_scale_16_to_8(row_info, png_ptr->row_buf + 1);
-#endif
-
-#ifdef PNG_READ_STRIP_16_TO_8_SUPPORTED
-   /* There is no harm in doing both of these because only one has any effect,
-    * by putting the 'scale' option first if the app asks for scale (either by
-    * calling the API or in a TRANSFORM flag) this is what happens.
-    */
-   if (png_ptr->transformations & PNG_16_TO_8)
-      png_do_chop(row_info, png_ptr->row_buf + 1);
-#endif
-
-#ifdef PNG_READ_QUANTIZE_SUPPORTED
-   if (png_ptr->transformations & PNG_QUANTIZE)
-   {
-      png_do_quantize(row_info, png_ptr->row_buf + 1,
-          png_ptr->palette_lookup, png_ptr->quantize_index);
-
-      if (row_info->rowbytes == 0)
-         dg_png_error(png_ptr, "png_do_quantize returned rowbytes=0");
-   }
-#endif /* PNG_READ_QUANTIZE_SUPPORTED */
-
-#ifdef PNG_READ_EXPAND_16_SUPPORTED
-   /* Do the expansion now, after all the arithmetic has been done.  Notice
-    * that previous transformations can handle the PNG_EXPAND_16 flag if this
-    * is efficient (particularly true in the case of gamma correction, where
-    * better accuracy results faster!)
-    */
-   if (png_ptr->transformations & PNG_EXPAND_16)
-      png_do_expand_16(row_info, png_ptr->row_buf + 1);
-#endif
-
-#ifdef PNG_READ_GRAY_TO_RGB_SUPPORTED
-   /* NOTE: moved here in 1.5.4 (from much later in this list.) */
-   if ((png_ptr->transformations & PNG_GRAY_TO_RGB) &&
-       (png_ptr->mode & PNG_BACKGROUND_IS_GRAY))
-      png_do_gray_to_rgb(row_info, png_ptr->row_buf + 1);
-#endif
-
-#ifdef PNG_READ_INVERT_SUPPORTED
-   if (png_ptr->transformations & PNG_INVERT_MONO)
-      png_do_invert(row_info, png_ptr->row_buf + 1);
-#endif
-
-#ifdef PNG_READ_SHIFT_SUPPORTED
-   if (png_ptr->transformations & PNG_SHIFT)
-      png_do_unshift(row_info, png_ptr->row_buf + 1,
-          &(png_ptr->shift));
-#endif
-
-#ifdef PNG_READ_PACK_SUPPORTED
-   if (png_ptr->transformations & PNG_PACK)
-      png_do_unpack(row_info, png_ptr->row_buf + 1);
-#endif
-
-#ifdef PNG_READ_CHECK_FOR_INVALID_INDEX_SUPPORTED
-   /* Added at libpng-1.5.10 */
-   if (row_info->color_type == PNG_COLOR_TYPE_PALETTE &&
-       png_ptr->num_palette_max >= 0)
-      png_do_check_palette_indexes(png_ptr, row_info);
-#endif
-
-#ifdef PNG_READ_BGR_SUPPORTED
-   if (png_ptr->transformations & PNG_BGR)
-      png_do_bgr(row_info, png_ptr->row_buf + 1);
-#endif
-
-#ifdef PNG_READ_PACKSWAP_SUPPORTED
-   if (png_ptr->transformations & PNG_PACKSWAP)
-      png_do_packswap(row_info, png_ptr->row_buf + 1);
-#endif
-
-#ifdef PNG_READ_FILLER_SUPPORTED
-   if (png_ptr->transformations & PNG_FILLER)
-      png_do_read_filler(row_info, png_ptr->row_buf + 1,
-          (png_uint_32)png_ptr->filler, png_ptr->flags);
-#endif
-
-#ifdef PNG_READ_INVERT_ALPHA_SUPPORTED
-   if (png_ptr->transformations & PNG_INVERT_ALPHA)
-      png_do_read_invert_alpha(row_info, png_ptr->row_buf + 1);
-#endif
-
-#ifdef PNG_READ_SWAP_ALPHA_SUPPORTED
-   if (png_ptr->transformations & PNG_SWAP_ALPHA)
-      png_do_read_swap_alpha(row_info, png_ptr->row_buf + 1);
-#endif
-
-#ifdef PNG_READ_16BIT_SUPPORTED
-#ifdef PNG_READ_SWAP_SUPPORTED
-   if (png_ptr->transformations & PNG_SWAP_BYTES)
-      png_do_swap(row_info, png_ptr->row_buf + 1);
-#endif
-#endif
-
-#ifdef PNG_READ_USER_TRANSFORM_SUPPORTED
-   if (png_ptr->transformations & PNG_USER_TRANSFORM)
-    {
-      if (png_ptr->read_user_transform_fn != NULL)
-         (*(png_ptr->read_user_transform_fn)) /* User read transform function */
-             (png_ptr,     /* png_ptr */
-             row_info,     /* row_info: */
-                /*  png_uint_32 width;       width of row */
-                /*  png_size_t rowbytes;     number of bytes in row */
-                /*  png_byte color_type;     color type of pixels */
-                /*  png_byte bit_depth;      bit depth of samples */
-                /*  png_byte channels;       number of channels (1-4) */
-                /*  png_byte pixel_depth;    bits per pixel (depth*channels) */
-             png_ptr->row_buf + 1);    /* start of pixel data for row */
-#ifdef PNG_USER_TRANSFORM_PTR_SUPPORTED
-      if (png_ptr->user_transform_depth)
-         row_info->bit_depth = png_ptr->user_transform_depth;
-
-      if (png_ptr->user_transform_channels)
-         row_info->channels = png_ptr->user_transform_channels;
-#endif
-      row_info->pixel_depth = (png_byte)(row_info->bit_depth *
-          row_info->channels);
-
-      row_info->rowbytes = PNG_ROWBYTES(row_info->pixel_depth, row_info->width);
-   }
-#endif
-}
-
-#ifdef PNG_READ_PACK_SUPPORTED
-/* Unpack pixels of 1, 2, or 4 bits per pixel into 1 byte per pixel,
- * without changing the actual values.  Thus, if you had a row with
- * a bit depth of 1, you would end up with bytes that only contained
- * the numbers 0 or 1.  If you would rather they contain 0 and 255, use
- * png_do_shift() after this.
- */
-void /* PRIVATE */
-png_do_unpack(png_row_infop row_info, png_bytep row)
-{
-   png_debug(1, "in png_do_unpack");
-
-   if (row_info->bit_depth < 8)
-   {
-      png_uint_32 i;
-      png_uint_32 row_width=row_info->width;
-
-      switch (row_info->bit_depth)
-      {
-         case 1:
-         {
-            png_bytep sp = row + (png_size_t)((row_width - 1) >> 3);
-            png_bytep dp = row + (png_size_t)row_width - 1;
-            png_uint_32 shift = 7 - (int)((row_width + 7) & 0x07);
-            for (i = 0; i < row_width; i++)
-            {
-               *dp = (png_byte)((*sp >> shift) & 0x01);
-
-               if (shift == 7)
-               {
-                  shift = 0;
-                  sp--;
-               }
-
-               else
-                  shift++;
-
-               dp--;
-            }
-            break;
-         }
-
-         case 2:
-         {
-
-            png_bytep sp = row + (png_size_t)((row_width - 1) >> 2);
-            png_bytep dp = row + (png_size_t)row_width - 1;
-            png_uint_32 shift = (int)((3 - ((row_width + 3) & 0x03)) << 1);
-            for (i = 0; i < row_width; i++)
-            {
-               *dp = (png_byte)((*sp >> shift) & 0x03);
-
-               if (shift == 6)
-               {
-                  shift = 0;
-                  sp--;
-               }
-
-               else
-                  shift += 2;
-
-               dp--;
-            }
-            break;
-         }
-
-         case 4:
-         {
-            png_bytep sp = row + (png_size_t)((row_width - 1) >> 1);
-            png_bytep dp = row + (png_size_t)row_width - 1;
-            png_uint_32 shift = (int)((1 - ((row_width + 1) & 0x01)) << 2);
-            for (i = 0; i < row_width; i++)
-            {
-               *dp = (png_byte)((*sp >> shift) & 0x0f);
-
-               if (shift == 4)
-               {
-                  shift = 0;
-                  sp--;
-               }
-
-               else
-                  shift = 4;
-
-               dp--;
-            }
-            break;
-         }
-
-         default:
-            break;
-      }
-      row_info->bit_depth = 8;
-      row_info->pixel_depth = (png_byte)(8 * row_info->channels);
-      row_info->rowbytes = row_width * row_info->channels;
-   }
-}
-#endif
-
-#ifdef PNG_READ_SHIFT_SUPPORTED
-/* Reverse the effects of png_do_shift.  This routine merely shifts the
- * pixels back to their significant bits values.  Thus, if you have
- * a row of bit depth 8, but only 5 are significant, this will shift
- * the values back to 0 through 31.
- */
-void /* PRIVATE */
-png_do_unshift(png_row_infop row_info, png_bytep row,
-    png_const_color_8p sig_bits)
-{
-   int color_type;
-
-   png_debug(1, "in png_do_unshift");
-
-   /* The palette case has already been handled in the _init routine. */
-   color_type = row_info->color_type;
-
-   if (color_type != PNG_COLOR_TYPE_PALETTE)
-   {
-      int shift[4];
-      int channels = 0;
-      int bit_depth = row_info->bit_depth;
-
-      if (color_type & PNG_COLOR_MASK_COLOR)
-      {
-         shift[channels++] = bit_depth - sig_bits->red;
-         shift[channels++] = bit_depth - sig_bits->green;
-         shift[channels++] = bit_depth - sig_bits->blue;
-      }
-
-      else
-      {
-         shift[channels++] = bit_depth - sig_bits->gray;
-      }
-
-      if (color_type & PNG_COLOR_MASK_ALPHA)
-      {
-         shift[channels++] = bit_depth - sig_bits->alpha;
-      }
-
-      {
-         int c, have_shift;
-
-         for (c = have_shift = 0; c < channels; ++c)
-         {
-            /* A shift of more than the bit depth is an error condition but it
-             * gets ignored here.
-             */
-            if (shift[c] <= 0 || shift[c] >= bit_depth)
-               shift[c] = 0;
-
-            else
-               have_shift = 1;
-         }
-
-         if (!have_shift)
-            return;
-      }
-
-      switch (bit_depth)
-      {
-         default:
-         /* Must be 1bpp gray: should not be here! */
-            /* NOTREACHED */
-            break;
-
-         case 2:
-         /* Must be 2bpp gray */
-         /* assert(channels == 1 && shift[0] == 1) */
-         {
-            png_bytep bp = row;
-            png_bytep bp_end = bp + row_info->rowbytes;
-
-            while (bp < bp_end)
-            {
-               int b = (*bp >> 1) & 0x55;
-               *bp++ = (png_byte)b;
-            }
-            break;
-         }
-
-         case 4:
-         /* Must be 4bpp gray */
-         /* assert(channels == 1) */
-         {
-            png_bytep bp = row;
-            png_bytep bp_end = bp + row_info->rowbytes;
-            int gray_shift = shift[0];
-            int mask =  0xf >> gray_shift;
-
-            mask |= mask << 4;
-
-            while (bp < bp_end)
-            {
-               int b = (*bp >> gray_shift) & mask;
-               *bp++ = (png_byte)b;
-            }
-            break;
-         }
-
-         case 8:
-         /* Single byte components, G, GA, RGB, RGBA */
-         {
-            png_bytep bp = row;
-            png_bytep bp_end = bp + row_info->rowbytes;
-            int channel = 0;
-
-            while (bp < bp_end)
-            {
-               int b = *bp >> shift[channel];
-               if (++channel >= channels)
-                  channel = 0;
-               *bp++ = (png_byte)b;
-            }
-            break;
-         }
-
-#ifdef PNG_READ_16BIT_SUPPORTED
-         case 16:
-         /* Double byte components, G, GA, RGB, RGBA */
-         {
-            png_bytep bp = row;
-            png_bytep bp_end = bp + row_info->rowbytes;
-            int channel = 0;
-
-            while (bp < bp_end)
-            {
-               int value = (bp[0] << 8) + bp[1];
-
-               value >>= shift[channel];
-               if (++channel >= channels)
-                  channel = 0;
-               *bp++ = (png_byte)(value >> 8);
-               *bp++ = (png_byte)(value & 0xff);
-            }
-            break;
-         }
-#endif
-      }
-   }
-}
-#endif
-
-#ifdef PNG_READ_SCALE_16_TO_8_SUPPORTED
-/* Scale rows of bit depth 16 down to 8 accurately */
-void /* PRIVATE */
-png_do_scale_16_to_8(png_row_infop row_info, png_bytep row)
-{
-   png_debug(1, "in png_do_scale_16_to_8");
-
-   if (row_info->bit_depth == 16)
-   {
-      png_bytep sp = row; /* source */
-      png_bytep dp = row; /* destination */
-      png_bytep ep = sp + row_info->rowbytes; /* end+1 */
-
-      while (sp < ep)
-      {
-         /* The input is an array of 16 bit components, these must be scaled to
-          * 8 bits each.  For a 16 bit value V the required value (from the PNG
-          * specification) is:
-          *
-          *    (V * 255) / 65535
-          *
-          * This reduces to round(V / 257), or floor((V + 128.5)/257)
-          *
-          * Represent V as the two byte value vhi.vlo.  Make a guess that the
-          * result is the top byte of V, vhi, then the correction to this value
-          * is:
-          *
-          *    error = floor(((V-vhi.vhi) + 128.5) / 257)
-          *          = floor(((vlo-vhi) + 128.5) / 257)
-          *
-          * This can be approximated using integer arithmetic (and a signed
-          * shift):
-          *
-          *    error = (vlo-vhi+128) >> 8;
-          *
-          * The approximate differs from the exact answer only when (vlo-vhi) is
-          * 128; it then gives a correction of +1 when the exact correction is
-          * 0.  This gives 128 errors.  The exact answer (correct for all 16 bit
-          * input values) is:
-          *
-          *    error = (vlo-vhi+128)*65535 >> 24;
-          *
-          * An alternative arithmetic calculation which also gives no errors is:
-          *
-          *    (V * 255 + 32895) >> 16
-          */
-
-         png_int_32 tmp = *sp++; /* must be signed! */
-         tmp += (((int)*sp++ - tmp + 128) * 65535) >> 24;
-         *dp++ = (png_byte)tmp;
-      }
-
-      row_info->bit_depth = 8;
-      row_info->pixel_depth = (png_byte)(8 * row_info->channels);
-      row_info->rowbytes = row_info->width * row_info->channels;
-   }
-}
-#endif
-
-#ifdef PNG_READ_STRIP_16_TO_8_SUPPORTED
-void /* PRIVATE */
-/* Simply discard the low byte.  This was the default behavior prior
- * to libpng-1.5.4.
- */
-png_do_chop(png_row_infop row_info, png_bytep row)
-{
-   png_debug(1, "in png_do_chop");
-
-   if (row_info->bit_depth == 16)
-   {
-      png_bytep sp = row; /* source */
-      png_bytep dp = row; /* destination */
-      png_bytep ep = sp + row_info->rowbytes; /* end+1 */
-
-      while (sp < ep)
-      {
-         *dp++ = *sp;
-         sp += 2; /* skip low byte */
-      }
-
-      row_info->bit_depth = 8;
-      row_info->pixel_depth = (png_byte)(8 * row_info->channels);
-      row_info->rowbytes = row_info->width * row_info->channels;
-   }
-}
-#endif
-
-#ifdef PNG_READ_SWAP_ALPHA_SUPPORTED
-void /* PRIVATE */
-png_do_read_swap_alpha(png_row_infop row_info, png_bytep row)
-{
-   png_debug(1, "in png_do_read_swap_alpha");
-
-   {
-      png_uint_32 row_width = row_info->width;
-      if (row_info->color_type == PNG_COLOR_TYPE_RGB_ALPHA)
-      {
-         /* This converts from RGBA to ARGB */
-         if (row_info->bit_depth == 8)
-         {
-            png_bytep sp = row + row_info->rowbytes;
-            png_bytep dp = sp;
-            png_byte save;
-            png_uint_32 i;
-
-            for (i = 0; i < row_width; i++)
-            {
-               save = *(--sp);
-               *(--dp) = *(--sp);
-               *(--dp) = *(--sp);
-               *(--dp) = *(--sp);
-               *(--dp) = save;
-            }
-         }
-
-#ifdef PNG_READ_16BIT_SUPPORTED
-         /* This converts from RRGGBBAA to AARRGGBB */
-         else
-         {
-            png_bytep sp = row + row_info->rowbytes;
-            png_bytep dp = sp;
-            png_byte save[2];
-            png_uint_32 i;
-
-            for (i = 0; i < row_width; i++)
-            {
-               save[0] = *(--sp);
-               save[1] = *(--sp);
-               *(--dp) = *(--sp);
-               *(--dp) = *(--sp);
-               *(--dp) = *(--sp);
-               *(--dp) = *(--sp);
-               *(--dp) = *(--sp);
-               *(--dp) = *(--sp);
-               *(--dp) = save[0];
-               *(--dp) = save[1];
-            }
-         }
-#endif
-      }
-
-      else if (row_info->color_type == PNG_COLOR_TYPE_GRAY_ALPHA)
-      {
-         /* This converts from GA to AG */
-         if (row_info->bit_depth == 8)
-         {
-            png_bytep sp = row + row_info->rowbytes;
-            png_bytep dp = sp;
-            png_byte save;
-            png_uint_32 i;
-
-            for (i = 0; i < row_width; i++)
-            {
-               save = *(--sp);
-               *(--dp) = *(--sp);
-               *(--dp) = save;
-            }
-         }
-
-#ifdef PNG_READ_16BIT_SUPPORTED
-         /* This converts from GGAA to AAGG */
-         else
-         {
-            png_bytep sp = row + row_info->rowbytes;
-            png_bytep dp = sp;
-            png_byte save[2];
-            png_uint_32 i;
-
-            for (i = 0; i < row_width; i++)
-            {
-               save[0] = *(--sp);
-               save[1] = *(--sp);
-               *(--dp) = *(--sp);
-               *(--dp) = *(--sp);
-               *(--dp) = save[0];
-               *(--dp) = save[1];
-            }
-         }
-#endif
-      }
-   }
-}
-#endif
-
-#ifdef PNG_READ_INVERT_ALPHA_SUPPORTED
-void /* PRIVATE */
-png_do_read_invert_alpha(png_row_infop row_info, png_bytep row)
-{
-   png_uint_32 row_width;
-   png_debug(1, "in png_do_read_invert_alpha");
-
-   row_width = row_info->width;
-   if (row_info->color_type == PNG_COLOR_TYPE_RGB_ALPHA)
-   {
-      if (row_info->bit_depth == 8)
-      {
-         /* This inverts the alpha channel in RGBA */
-         png_bytep sp = row + row_info->rowbytes;
-         png_bytep dp = sp;
-         png_uint_32 i;
-
-         for (i = 0; i < row_width; i++)
-         {
-            *(--dp) = (png_byte)(255 - *(--sp));
-
-/*          This does nothing:
-            *(--dp) = *(--sp);
-            *(--dp) = *(--sp);
-            *(--dp) = *(--sp);
-            We can replace it with:
-*/
-            sp-=3;
-            dp=sp;
-         }
-      }
-
-#ifdef PNG_READ_16BIT_SUPPORTED
-      /* This inverts the alpha channel in RRGGBBAA */
-      else
-      {
-         png_bytep sp = row + row_info->rowbytes;
-         png_bytep dp = sp;
-         png_uint_32 i;
-
-         for (i = 0; i < row_width; i++)
-         {
-            *(--dp) = (png_byte)(255 - *(--sp));
-            *(--dp) = (png_byte)(255 - *(--sp));
-
-/*          This does nothing:
-            *(--dp) = *(--sp);
-            *(--dp) = *(--sp);
-            *(--dp) = *(--sp);
-            *(--dp) = *(--sp);
-            *(--dp) = *(--sp);
-            *(--dp) = *(--sp);
-            We can replace it with:
-*/
-            sp-=6;
-            dp=sp;
-         }
-      }
-#endif
-   }
-   else if (row_info->color_type == PNG_COLOR_TYPE_GRAY_ALPHA)
-   {
-      if (row_info->bit_depth == 8)
-      {
-         /* This inverts the alpha channel in GA */
-         png_bytep sp = row + row_info->rowbytes;
-         png_bytep dp = sp;
-         png_uint_32 i;
-
-         for (i = 0; i < row_width; i++)
-         {
-            *(--dp) = (png_byte)(255 - *(--sp));
-            *(--dp) = *(--sp);
-         }
-      }
-
-#ifdef PNG_READ_16BIT_SUPPORTED
-      else
-      {
-         /* This inverts the alpha channel in GGAA */
-         png_bytep sp  = row + row_info->rowbytes;
-         png_bytep dp = sp;
-         png_uint_32 i;
-
-         for (i = 0; i < row_width; i++)
-         {
-            *(--dp) = (png_byte)(255 - *(--sp));
-            *(--dp) = (png_byte)(255 - *(--sp));
-/*
-            *(--dp) = *(--sp);
-            *(--dp) = *(--sp);
-*/
-            sp-=2;
-            dp=sp;
-         }
-      }
-#endif
-   }
-}
-#endif
-
-#ifdef PNG_READ_FILLER_SUPPORTED
-/* Add filler channel if we have RGB color */
-void /* PRIVATE */
-png_do_read_filler(png_row_infop row_info, png_bytep row,
-    png_uint_32 filler, png_uint_32 flags)
-{
-   png_uint_32 i;
-   png_uint_32 row_width = row_info->width;
-
-#ifdef PNG_READ_16BIT_SUPPORTED
-   png_byte hi_filler = (png_byte)((filler>>8) & 0xff);
-#endif
-   png_byte lo_filler = (png_byte)(filler & 0xff);
-
-   png_debug(1, "in png_do_read_filler");
-
-   if (
-       row_info->color_type == PNG_COLOR_TYPE_GRAY)
-   {
-      if (row_info->bit_depth == 8)
-      {
-         if (flags & PNG_FLAG_FILLER_AFTER)
-         {
-            /* This changes the data from G to GX */
-            png_bytep sp = row + (png_size_t)row_width;
-            png_bytep dp =  sp + (png_size_t)row_width;
-            for (i = 1; i < row_width; i++)
-            {
-               *(--dp) = lo_filler;
-               *(--dp) = *(--sp);
-            }
-            *(--dp) = lo_filler;
-            row_info->channels = 2;
-            row_info->pixel_depth = 16;
-            row_info->rowbytes = row_width * 2;
-         }
-
-         else
-         {
-            /* This changes the data from G to XG */
-            png_bytep sp = row + (png_size_t)row_width;
-            png_bytep dp = sp  + (png_size_t)row_width;
-            for (i = 0; i < row_width; i++)
-            {
-               *(--dp) = *(--sp);
-               *(--dp) = lo_filler;
-            }
-            row_info->channels = 2;
-            row_info->pixel_depth = 16;
-            row_info->rowbytes = row_width * 2;
-         }
-      }
-
-#ifdef PNG_READ_16BIT_SUPPORTED
-      else if (row_info->bit_depth == 16)
-      {
-         if (flags & PNG_FLAG_FILLER_AFTER)
-         {
-            /* This changes the data from GG to GGXX */
-            png_bytep sp = row + (png_size_t)row_width * 2;
-            png_bytep dp = sp  + (png_size_t)row_width * 2;
-            for (i = 1; i < row_width; i++)
-            {
-               *(--dp) = hi_filler;
-               *(--dp) = lo_filler;
-               *(--dp) = *(--sp);
-               *(--dp) = *(--sp);
-            }
-            *(--dp) = hi_filler;
-            *(--dp) = lo_filler;
-            row_info->channels = 2;
-            row_info->pixel_depth = 32;
-            row_info->rowbytes = row_width * 4;
-         }
-
-         else
-         {
-            /* This changes the data from GG to XXGG */
-            png_bytep sp = row + (png_size_t)row_width * 2;
-            png_bytep dp = sp  + (png_size_t)row_width * 2;
-            for (i = 0; i < row_width; i++)
-            {
-               *(--dp) = *(--sp);
-               *(--dp) = *(--sp);
-               *(--dp) = hi_filler;
-               *(--dp) = lo_filler;
-            }
-            row_info->channels = 2;
-            row_info->pixel_depth = 32;
-            row_info->rowbytes = row_width * 4;
-         }
-      }
-#endif
-   } /* COLOR_TYPE == GRAY */
-   else if (row_info->color_type == PNG_COLOR_TYPE_RGB)
-   {
-      if (row_info->bit_depth == 8)
-      {
-         if (flags & PNG_FLAG_FILLER_AFTER)
-         {
-            /* This changes the data from RGB to RGBX */
-            png_bytep sp = row + (png_size_t)row_width * 3;
-            png_bytep dp = sp  + (png_size_t)row_width;
-            for (i = 1; i < row_width; i++)
-            {
-               *(--dp) = lo_filler;
-               *(--dp) = *(--sp);
-               *(--dp) = *(--sp);
-               *(--dp) = *(--sp);
-            }
-            *(--dp) = lo_filler;
-            row_info->channels = 4;
-            row_info->pixel_depth = 32;
-            row_info->rowbytes = row_width * 4;
-         }
-
-         else
-         {
-            /* This changes the data from RGB to XRGB */
-            png_bytep sp = row + (png_size_t)row_width * 3;
-            png_bytep dp = sp + (png_size_t)row_width;
-            for (i = 0; i < row_width; i++)
-            {
-               *(--dp) = *(--sp);
-               *(--dp) = *(--sp);
-               *(--dp) = *(--sp);
-               *(--dp) = lo_filler;
-            }
-            row_info->channels = 4;
-            row_info->pixel_depth = 32;
-            row_info->rowbytes = row_width * 4;
-         }
-      }
-
-#ifdef PNG_READ_16BIT_SUPPORTED
-      else if (row_info->bit_depth == 16)
-      {
-         if (flags & PNG_FLAG_FILLER_AFTER)
-         {
-            /* This changes the data from RRGGBB to RRGGBBXX */
-            png_bytep sp = row + (png_size_t)row_width * 6;
-            png_bytep dp = sp  + (png_size_t)row_width * 2;
-            for (i = 1; i < row_width; i++)
-            {
-               *(--dp) = hi_filler;
-               *(--dp) = lo_filler;
-               *(--dp) = *(--sp);
-               *(--dp) = *(--sp);
-               *(--dp) = *(--sp);
-               *(--dp) = *(--sp);
-               *(--dp) = *(--sp);
-               *(--dp) = *(--sp);
-            }
-            *(--dp) = hi_filler;
-            *(--dp) = lo_filler;
-            row_info->channels = 4;
-            row_info->pixel_depth = 64;
-            row_info->rowbytes = row_width * 8;
-         }
-
-         else
-         {
-            /* This changes the data from RRGGBB to XXRRGGBB */
-            png_bytep sp = row + (png_size_t)row_width * 6;
-            png_bytep dp = sp  + (png_size_t)row_width * 2;
-            for (i = 0; i < row_width; i++)
-            {
-               *(--dp) = *(--sp);
-               *(--dp) = *(--sp);
-               *(--dp) = *(--sp);
-               *(--dp) = *(--sp);
-               *(--dp) = *(--sp);
-               *(--dp) = *(--sp);
-               *(--dp) = hi_filler;
-               *(--dp) = lo_filler;
-            }
-
-            row_info->channels = 4;
-            row_info->pixel_depth = 64;
-            row_info->rowbytes = row_width * 8;
-         }
-      }
-#endif
-   } /* COLOR_TYPE == RGB */
-}
-#endif
-
-#ifdef PNG_READ_GRAY_TO_RGB_SUPPORTED
-/* Expand grayscale files to RGB, with or without alpha */
-void /* PRIVATE */
-png_do_gray_to_rgb(png_row_infop row_info, png_bytep row)
-{
-   png_uint_32 i;
-   png_uint_32 row_width = row_info->width;
-
-   png_debug(1, "in png_do_gray_to_rgb");
-
-   if (row_info->bit_depth >= 8 &&
-       !(row_info->color_type & PNG_COLOR_MASK_COLOR))
-   {
-      if (row_info->color_type == PNG_COLOR_TYPE_GRAY)
-      {
-         if (row_info->bit_depth == 8)
-         {
-            /* This changes G to RGB */
-            png_bytep sp = row + (png_size_t)row_width - 1;
-            png_bytep dp = sp  + (png_size_t)row_width * 2;
-            for (i = 0; i < row_width; i++)
-            {
-               *(dp--) = *sp;
-               *(dp--) = *sp;
-               *(dp--) = *(sp--);
-            }
-         }
-
-         else
-         {
-            /* This changes GG to RRGGBB */
-            png_bytep sp = row + (png_size_t)row_width * 2 - 1;
-            png_bytep dp = sp  + (png_size_t)row_width * 4;
-            for (i = 0; i < row_width; i++)
-            {
-               *(dp--) = *sp;
-               *(dp--) = *(sp - 1);
-               *(dp--) = *sp;
-               *(dp--) = *(sp - 1);
-               *(dp--) = *(sp--);
-               *(dp--) = *(sp--);
-            }
-         }
-      }
-
-      else if (row_info->color_type == PNG_COLOR_TYPE_GRAY_ALPHA)
-      {
-         if (row_info->bit_depth == 8)
-         {
-            /* This changes GA to RGBA */
-            png_bytep sp = row + (png_size_t)row_width * 2 - 1;
-            png_bytep dp = sp  + (png_size_t)row_width * 2;
-            for (i = 0; i < row_width; i++)
-            {
-               *(dp--) = *(sp--);
-               *(dp--) = *sp;
-               *(dp--) = *sp;
-               *(dp--) = *(sp--);
-            }
-         }
-
-         else
-         {
-            /* This changes GGAA to RRGGBBAA */
-            png_bytep sp = row + (png_size_t)row_width * 4 - 1;
-            png_bytep dp = sp  + (png_size_t)row_width * 4;
-            for (i = 0; i < row_width; i++)
-            {
-               *(dp--) = *(sp--);
-               *(dp--) = *(sp--);
-               *(dp--) = *sp;
-               *(dp--) = *(sp - 1);
-               *(dp--) = *sp;
-               *(dp--) = *(sp - 1);
-               *(dp--) = *(sp--);
-               *(dp--) = *(sp--);
-            }
-         }
-      }
-      row_info->channels = (png_byte)(row_info->channels + 2);
-      row_info->color_type |= PNG_COLOR_MASK_COLOR;
-      row_info->pixel_depth = (png_byte)(row_info->channels *
-          row_info->bit_depth);
-      row_info->rowbytes = PNG_ROWBYTES(row_info->pixel_depth, row_width);
-   }
-}
-#endif
-
-#ifdef PNG_READ_RGB_TO_GRAY_SUPPORTED
-/* Reduce RGB files to grayscale, with or without alpha
- * using the equation given in Poynton's ColorFAQ of 1998-01-04 at
- * <http://www.inforamp.net/~poynton/>  (THIS LINK IS DEAD June 2008 but
- * versions dated 1998 through November 2002 have been archived at
- * http://web.archive.org/web/20000816232553/http://www.inforamp.net/
- * ~poynton/notes/colour_and_gamma/ColorFAQ.txt )
- * Charles Poynton poynton at poynton.com
- *
- *     Y = 0.212671 * R + 0.715160 * G + 0.072169 * B
- *
- *  which can be expressed with integers as
- *
- *     Y = (6969 * R + 23434 * G + 2365 * B)/32768
- *
- * Poynton's current link (as of January 2003 through July 2011):
- * <http://www.poynton.com/notes/colour_and_gamma/>
- * has changed the numbers slightly:
- *
- *     Y = 0.2126*R + 0.7152*G + 0.0722*B
- *
- *  which can be expressed with integers as
- *
- *     Y = (6966 * R + 23436 * G + 2366 * B)/32768
- *
- *  Historically, however, libpng uses numbers derived from the ITU-R Rec 709
- *  end point chromaticities and the D65 white point.  Depending on the
- *  precision used for the D65 white point this produces a variety of different
- *  numbers, however if the four decimal place value used in ITU-R Rec 709 is
- *  used (0.3127,0.3290) the Y calculation would be:
- *
- *     Y = (6968 * R + 23435 * G + 2366 * B)/32768
- *
- *  While this is correct the rounding results in an overflow for white, because
- *  the sum of the rounded coefficients is 32769, not 32768.  Consequently
- *  libpng uses, instead, the closest non-overflowing approximation:
- *
- *     Y = (6968 * R + 23434 * G + 2366 * B)/32768
- *
- *  Starting with libpng-1.5.5, if the image being converted has a cHRM chunk
- *  (including an sRGB chunk) then the chromaticities are used to calculate the
- *  coefficients.  See the chunk handling in pngrutil.c for more information.
- *
- *  In all cases the calculation is to be done in a linear colorspace.  If no
- *  gamma information is available to correct the encoding of the original RGB
- *  values this results in an implicit assumption that the original PNG RGB
- *  values were linear.
- *
- *  Other integer coefficents can be used via png_set_rgb_to_gray().  Because
- *  the API takes just red and green coefficients the blue coefficient is
- *  calculated to make the sum 32768.  This will result in different rounding
- *  to that used above.
- */
-int /* PRIVATE */
-png_do_rgb_to_gray(png_structp png_ptr, png_row_infop row_info, png_bytep row)
-
-{
-   int rgb_error = 0;
-
-   png_debug(1, "in png_do_rgb_to_gray");
-
-   if (!(row_info->color_type & PNG_COLOR_MASK_PALETTE) &&
-       (row_info->color_type & PNG_COLOR_MASK_COLOR))
-   {
-      PNG_CONST png_uint_32 rc = png_ptr->rgb_to_gray_red_coeff;
-      PNG_CONST png_uint_32 gc = png_ptr->rgb_to_gray_green_coeff;
-      PNG_CONST png_uint_32 bc = 32768 - rc - gc;
-      PNG_CONST png_uint_32 row_width = row_info->width;
-      PNG_CONST int have_alpha =
-         (row_info->color_type & PNG_COLOR_MASK_ALPHA) != 0;
-
-      if (row_info->bit_depth == 8)
-      {
-#if defined(PNG_READ_GAMMA_SUPPORTED) || defined(PNG_READ_BACKGROUND_SUPPORTED)
-         /* Notice that gamma to/from 1 are not necessarily inverses (if
-          * there is an overall gamma correction).  Prior to 1.5.5 this code
-          * checked the linearized values for equality; this doesn't match
-          * the documentation, the original values must be checked.
-          */
-         if (png_ptr->gamma_from_1 != NULL && png_ptr->gamma_to_1 != NULL)
-         {
-            png_bytep sp = row;
-            png_bytep dp = row;
-            png_uint_32 i;
-
-            for (i = 0; i < row_width; i++)
-            {
-               png_byte red   = *(sp++);
-               png_byte green = *(sp++);
-               png_byte blue  = *(sp++);
-
-               if (red != green || red != blue)
-               {
-                  red = png_ptr->gamma_to_1[red];
-                  green = png_ptr->gamma_to_1[green];
-                  blue = png_ptr->gamma_to_1[blue];
-
-                  rgb_error |= 1;
-                  *(dp++) = png_ptr->gamma_from_1[
-                      (rc*red + gc*green + bc*blue + 16384)>>15];
-               }
-
-               else
-               {
-                  /* If there is no overall correction the table will not be
-                   * set.
-                   */
-                  if (png_ptr->gamma_table != NULL)
-                     red = png_ptr->gamma_table[red];
-
-                  *(dp++) = red;
-               }
-
-               if (have_alpha)
-                  *(dp++) = *(sp++);
-            }
-         }
-         else
-#endif
-         {
-            png_bytep sp = row;
-            png_bytep dp = row;
-            png_uint_32 i;
-
-            for (i = 0; i < row_width; i++)
-            {
-               png_byte red   = *(sp++);
-               png_byte green = *(sp++);
-               png_byte blue  = *(sp++);
-
-               if (red != green || red != blue)
-               {
-                  rgb_error |= 1;
-                  /* NOTE: this is the historical approach which simply
-                   * truncates the results.
-                   */
-                  *(dp++) = (png_byte)((rc*red + gc*green + bc*blue)>>15);
-               }
-
-               else
-                  *(dp++) = red;
-
-               if (have_alpha)
-                  *(dp++) = *(sp++);
-            }
-         }
-      }
-
-      else /* RGB bit_depth == 16 */
-      {
-#if defined(PNG_READ_GAMMA_SUPPORTED) || defined(PNG_READ_BACKGROUND_SUPPORTED)
-         if (png_ptr->gamma_16_to_1 != NULL && png_ptr->gamma_16_from_1 != NULL)
-         {
-            png_bytep sp = row;
-            png_bytep dp = row;
-            png_uint_32 i;
-
-            for (i = 0; i < row_width; i++)
-            {
-               png_uint_16 red, green, blue, w;
-
-               red   = (png_uint_16)(((*(sp))<<8) | *(sp + 1)); sp += 2;
-               green = (png_uint_16)(((*(sp))<<8) | *(sp + 1)); sp += 2;
-               blue  = (png_uint_16)(((*(sp))<<8) | *(sp + 1)); sp += 2;
-
-               if (red == green && red == blue)
-               {
-                  if (png_ptr->gamma_16_table != NULL)
-                     w = png_ptr->gamma_16_table[(red&0xff)
-                         >> png_ptr->gamma_shift][red>>8];
-
-                  else
-                     w = red;
-               }
-
-               else
-               {
-                  png_uint_16 red_1   = png_ptr->gamma_16_to_1[(red&0xff)
-                      >> png_ptr->gamma_shift][red>>8];
-                  png_uint_16 green_1 =
-                      png_ptr->gamma_16_to_1[(green&0xff) >>
-                      png_ptr->gamma_shift][green>>8];
-                  png_uint_16 blue_1  = png_ptr->gamma_16_to_1[(blue&0xff)
-                      >> png_ptr->gamma_shift][blue>>8];
-                  png_uint_16 gray16  = (png_uint_16)((rc*red_1 + gc*green_1
-                      + bc*blue_1 + 16384)>>15);
-                  w = png_ptr->gamma_16_from_1[(gray16&0xff) >>
-                      png_ptr->gamma_shift][gray16 >> 8];
-                  rgb_error |= 1;
-               }
-
-               *(dp++) = (png_byte)((w>>8) & 0xff);
-               *(dp++) = (png_byte)(w & 0xff);
-
-               if (have_alpha)
-               {
-                  *(dp++) = *(sp++);
-                  *(dp++) = *(sp++);
-               }
-            }
-         }
-         else
-#endif
-         {
-            png_bytep sp = row;
-            png_bytep dp = row;
-            png_uint_32 i;
-
-            for (i = 0; i < row_width; i++)
-            {
-               png_uint_16 red, green, blue, gray16;
-
-               red   = (png_uint_16)(((*(sp))<<8) | *(sp + 1)); sp += 2;
-               green = (png_uint_16)(((*(sp))<<8) | *(sp + 1)); sp += 2;
-               blue  = (png_uint_16)(((*(sp))<<8) | *(sp + 1)); sp += 2;
-
-               if (red != green || red != blue)
-                  rgb_error |= 1;
-
-               /* From 1.5.5 in the 16 bit case do the accurate conversion even
-                * in the 'fast' case - this is because this is where the code
-                * ends up when handling linear 16 bit data.
-                */
-               gray16  = (png_uint_16)((rc*red + gc*green + bc*blue + 16384) >>
-                  15);
-               *(dp++) = (png_byte)((gray16>>8) & 0xff);
-               *(dp++) = (png_byte)(gray16 & 0xff);
-
-               if (have_alpha)
-               {
-                  *(dp++) = *(sp++);
-                  *(dp++) = *(sp++);
-               }
-            }
-         }
-      }
-
-      row_info->channels = (png_byte)(row_info->channels - 2);
-      row_info->color_type = (png_byte)(row_info->color_type &
-          ~PNG_COLOR_MASK_COLOR);
-      row_info->pixel_depth = (png_byte)(row_info->channels *
-          row_info->bit_depth);
-      row_info->rowbytes = PNG_ROWBYTES(row_info->pixel_depth, row_width);
-   }
-   return rgb_error;
-}
-#endif
-#endif /* PNG_READ_TRANSFORMS_SUPPORTED */
-
-#ifdef PNG_BUILD_GRAYSCALE_PALETTE_SUPPORTED
-/* Build a grayscale palette.  Palette is assumed to be 1 << bit_depth
- * large of png_color.  This lets grayscale images be treated as
- * paletted.  Most useful for gamma correction and simplification
- * of code.  This API is not used internally.
- */
-void PNGAPI
-png_build_grayscale_palette(int bit_depth, png_colorp palette)
-{
-   int num_palette;
-   int color_inc;
-   int i;
-   int v;
-
-   png_debug(1, "in png_do_build_grayscale_palette");
-
-   if (palette == NULL)
-      return;
-
-   switch (bit_depth)
-   {
-      case 1:
-         num_palette = 2;
-         color_inc = 0xff;
-         break;
-
-      case 2:
-         num_palette = 4;
-         color_inc = 0x55;
-         break;
-
-      case 4:
-         num_palette = 16;
-         color_inc = 0x11;
-         break;
-
-      case 8:
-         num_palette = 256;
-         color_inc = 1;
-         break;
-
-      default:
-         num_palette = 0;
-         color_inc = 0;
-         break;
-   }
-
-   for (i = 0, v = 0; i < num_palette; i++, v += color_inc)
-   {
-      palette[i].red = (png_byte)v;
-      palette[i].green = (png_byte)v;
-      palette[i].blue = (png_byte)v;
-   }
-}
-#endif
-
-
-#ifdef PNG_READ_TRANSFORMS_SUPPORTED
-#if (defined PNG_READ_BACKGROUND_SUPPORTED) ||\
-   (defined PNG_READ_ALPHA_MODE_SUPPORTED)
-/* Replace any alpha or transparency with the supplied background color.
- * "background" is already in the screen gamma, while "background_1" is
- * at a gamma of 1.0.  Paletted files have already been taken care of.
- */
-void /* PRIVATE */
-png_do_compose(png_row_infop row_info, png_bytep row, png_structp png_ptr)
-{
-#ifdef PNG_READ_GAMMA_SUPPORTED
-   png_const_bytep gamma_table = png_ptr->gamma_table;
-   png_const_bytep gamma_from_1 = png_ptr->gamma_from_1;
-   png_const_bytep gamma_to_1 = png_ptr->gamma_to_1;
-   png_const_uint_16pp gamma_16 = png_ptr->gamma_16_table;
-   png_const_uint_16pp gamma_16_from_1 = png_ptr->gamma_16_from_1;
-   png_const_uint_16pp gamma_16_to_1 = png_ptr->gamma_16_to_1;
-   int gamma_shift = png_ptr->gamma_shift;
-#endif
-
-   png_bytep sp;
-   png_uint_32 i;
-   png_uint_32 row_width = row_info->width;
-   int optimize = (png_ptr->flags & PNG_FLAG_OPTIMIZE_ALPHA) != 0;
-   int shift;
-
-   png_debug(1, "in png_do_compose");
-
-   {
-      switch (row_info->color_type)
-      {
-         case PNG_COLOR_TYPE_GRAY:
-         {
-            switch (row_info->bit_depth)
-            {
-               case 1:
-               {
-                  sp = row;
-                  shift = 7;
-                  for (i = 0; i < row_width; i++)
-                  {
-                     if ((png_uint_16)((*sp >> shift) & 0x01)
-                        == png_ptr->trans_color.gray)
-                     {
-                        *sp &= (png_byte)((0x7f7f >> (7 - shift)) & 0xff);
-                        *sp |= (png_byte)(png_ptr->background.gray << shift);
-                     }
-
-                     if (!shift)
-                     {
-                        shift = 7;
-                        sp++;
-                     }
-
-                     else
-                        shift--;
-                  }
-                  break;
-               }
-
-               case 2:
-               {
-#ifdef PNG_READ_GAMMA_SUPPORTED
-                  if (gamma_table != NULL)
-                  {
-                     sp = row;
-                     shift = 6;
-                     for (i = 0; i < row_width; i++)
-                     {
-                        if ((png_uint_16)((*sp >> shift) & 0x03)
-                            == png_ptr->trans_color.gray)
-                        {
-                           *sp &= (png_byte)((0x3f3f >> (6 - shift)) & 0xff);
-                           *sp |= (png_byte)(png_ptr->background.gray << shift);
-                        }
-
-                        else
-                        {
-                           png_byte p = (png_byte)((*sp >> shift) & 0x03);
-                           png_byte g = (png_byte)((gamma_table [p | (p << 2) |
-                               (p << 4) | (p << 6)] >> 6) & 0x03);
-                           *sp &= (png_byte)((0x3f3f >> (6 - shift)) & 0xff);
-                           *sp |= (png_byte)(g << shift);
-                        }
-
-                        if (!shift)
-                        {
-                           shift = 6;
-                           sp++;
-                        }
-
-                        else
-                           shift -= 2;
-                     }
-                  }
-
-                  else
-#endif
-                  {
-                     sp = row;
-                     shift = 6;
-                     for (i = 0; i < row_width; i++)
-                     {
-                        if ((png_uint_16)((*sp >> shift) & 0x03)
-                            == png_ptr->trans_color.gray)
-                        {
-                           *sp &= (png_byte)((0x3f3f >> (6 - shift)) & 0xff);
-                           *sp |= (png_byte)(png_ptr->background.gray << shift);
-                        }
-
-                        if (!shift)
-                        {
-                           shift = 6;
-                           sp++;
-                        }
-
-                        else
-                           shift -= 2;
-                     }
-                  }
-                  break;
-               }
-
-               case 4:
-               {
-#ifdef PNG_READ_GAMMA_SUPPORTED
-                  if (gamma_table != NULL)
-                  {
-                     sp = row;
-                     shift = 4;
-                     for (i = 0; i < row_width; i++)
-                     {
-                        if ((png_uint_16)((*sp >> shift) & 0x0f)
-                            == png_ptr->trans_color.gray)
-                        {
-                           *sp &= (png_byte)((0xf0f >> (4 - shift)) & 0xff);
-                           *sp |= (png_byte)(png_ptr->background.gray << shift);
-                        }
-
-                        else
-                        {
-                           png_byte p = (png_byte)((*sp >> shift) & 0x0f);
-                           png_byte g = (png_byte)((gamma_table[p |
-                               (p << 4)] >> 4) & 0x0f);
-                           *sp &= (png_byte)((0xf0f >> (4 - shift)) & 0xff);
-                           *sp |= (png_byte)(g << shift);
-                        }
-
-                        if (!shift)
-                        {
-                           shift = 4;
-                           sp++;
-                        }
-
-                        else
-                           shift -= 4;
-                     }
-                  }
-
-                  else
-#endif
-                  {
-                     sp = row;
-                     shift = 4;
-                     for (i = 0; i < row_width; i++)
-                     {
-                        if ((png_uint_16)((*sp >> shift) & 0x0f)
-                            == png_ptr->trans_color.gray)
-                        {
-                           *sp &= (png_byte)((0xf0f >> (4 - shift)) & 0xff);
-                           *sp |= (png_byte)(png_ptr->background.gray << shift);
-                        }
-
-                        if (!shift)
-                        {
-                           shift = 4;
-                           sp++;
-                        }
-
-                        else
-                           shift -= 4;
-                     }
-                  }
-                  break;
-               }
-
-               case 8:
-               {
-#ifdef PNG_READ_GAMMA_SUPPORTED
-                  if (gamma_table != NULL)
-                  {
-                     sp = row;
-                     for (i = 0; i < row_width; i++, sp++)
-                     {
-                        if (*sp == png_ptr->trans_color.gray)
-                           *sp = (png_byte)png_ptr->background.gray;
-
-                        else
-                           *sp = gamma_table[*sp];
-                     }
-                  }
-                  else
-#endif
-                  {
-                     sp = row;
-                     for (i = 0; i < row_width; i++, sp++)
-                     {
-                        if (*sp == png_ptr->trans_color.gray)
-                           *sp = (png_byte)png_ptr->background.gray;
-                     }
-                  }
-                  break;
-               }
-
-               case 16:
-               {
-#ifdef PNG_READ_GAMMA_SUPPORTED
-                  if (gamma_16 != NULL)
-                  {
-                     sp = row;
-                     for (i = 0; i < row_width; i++, sp += 2)
-                     {
-                        png_uint_16 v;
-
-                        v = (png_uint_16)(((*sp) << 8) + *(sp + 1));
-
-                        if (v == png_ptr->trans_color.gray)
-                        {
-                           /* Background is already in screen gamma */
-                           *sp = (png_byte)((png_ptr->background.gray >> 8)
-                                & 0xff);
-                           *(sp + 1) = (png_byte)(png_ptr->background.gray
-                                & 0xff);
-                        }
-
-                        else
-                        {
-                           v = gamma_16[*(sp + 1) >> gamma_shift][*sp];
-                           *sp = (png_byte)((v >> 8) & 0xff);
-                           *(sp + 1) = (png_byte)(v & 0xff);
-                        }
-                     }
-                  }
-                  else
-#endif
-                  {
-                     sp = row;
-                     for (i = 0; i < row_width; i++, sp += 2)
-                     {
-                        png_uint_16 v;
-
-                        v = (png_uint_16)(((*sp) << 8) + *(sp + 1));
-
-                        if (v == png_ptr->trans_color.gray)
-                        {
-                           *sp = (png_byte)((png_ptr->background.gray >> 8)
-                                & 0xff);
-                           *(sp + 1) = (png_byte)(png_ptr->background.gray
-                                & 0xff);
-                        }
-                     }
-                  }
-                  break;
-               }
-
-               default:
-                  break;
-            }
-            break;
-         }
-
-         case PNG_COLOR_TYPE_RGB:
-         {
-            if (row_info->bit_depth == 8)
-            {
-#ifdef PNG_READ_GAMMA_SUPPORTED
-               if (gamma_table != NULL)
-               {
-                  sp = row;
-                  for (i = 0; i < row_width; i++, sp += 3)
-                  {
-                     if (*sp == png_ptr->trans_color.red &&
-                         *(sp + 1) == png_ptr->trans_color.green &&
-                         *(sp + 2) == png_ptr->trans_color.blue)
-                     {
-                        *sp = (png_byte)png_ptr->background.red;
-                        *(sp + 1) = (png_byte)png_ptr->background.green;
-                        *(sp + 2) = (png_byte)png_ptr->background.blue;
-                     }
-
-                     else
-                     {
-                        *sp = gamma_table[*sp];
-                        *(sp + 1) = gamma_table[*(sp + 1)];
-                        *(sp + 2) = gamma_table[*(sp + 2)];
-                     }
-                  }
-               }
-               else
-#endif
-               {
-                  sp = row;
-                  for (i = 0; i < row_width; i++, sp += 3)
-                  {
-                     if (*sp == png_ptr->trans_color.red &&
-                         *(sp + 1) == png_ptr->trans_color.green &&
-                         *(sp + 2) == png_ptr->trans_color.blue)
-                     {
-                        *sp = (png_byte)png_ptr->background.red;
-                        *(sp + 1) = (png_byte)png_ptr->background.green;
-                        *(sp + 2) = (png_byte)png_ptr->background.blue;
-                     }
-                  }
-               }
-            }
-            else /* if (row_info->bit_depth == 16) */
-            {
-#ifdef PNG_READ_GAMMA_SUPPORTED
-               if (gamma_16 != NULL)
-               {
-                  sp = row;
-                  for (i = 0; i < row_width; i++, sp += 6)
-                  {
-                     png_uint_16 r = (png_uint_16)(((*sp) << 8) + *(sp + 1));
-
-                     png_uint_16 g = (png_uint_16)(((*(sp + 2)) << 8)
-                         + *(sp + 3));
-
-                     png_uint_16 b = (png_uint_16)(((*(sp + 4)) << 8)
-                         + *(sp + 5));
-
-                     if (r == png_ptr->trans_color.red &&
-                         g == png_ptr->trans_color.green &&
-                         b == png_ptr->trans_color.blue)
-                     {
-                        /* Background is already in screen gamma */
-                        *sp = (png_byte)((png_ptr->background.red >> 8) & 0xff);
-                        *(sp + 1) = (png_byte)(png_ptr->background.red & 0xff);
-                        *(sp + 2) = (png_byte)((png_ptr->background.green >> 8)
-                                & 0xff);
-                        *(sp + 3) = (png_byte)(png_ptr->background.green
-                                & 0xff);
-                        *(sp + 4) = (png_byte)((png_ptr->background.blue >> 8)
-                                & 0xff);
-                        *(sp + 5) = (png_byte)(png_ptr->background.blue & 0xff);
-                     }
-
-                     else
-                     {
-                        png_uint_16 v = gamma_16[*(sp + 1) >> gamma_shift][*sp];
-                        *sp = (png_byte)((v >> 8) & 0xff);
-                        *(sp + 1) = (png_byte)(v & 0xff);
-
-                        v = gamma_16[*(sp + 3) >> gamma_shift][*(sp + 2)];
-                        *(sp + 2) = (png_byte)((v >> 8) & 0xff);
-                        *(sp + 3) = (png_byte)(v & 0xff);
-
-                        v = gamma_16[*(sp + 5) >> gamma_shift][*(sp + 4)];
-                        *(sp + 4) = (png_byte)((v >> 8) & 0xff);
-                        *(sp + 5) = (png_byte)(v & 0xff);
-                     }
-                  }
-               }
-
-               else
-#endif
-               {
-                  sp = row;
-                  for (i = 0; i < row_width; i++, sp += 6)
-                  {
-                     png_uint_16 r = (png_uint_16)(((*sp) << 8) + *(sp + 1));
-
-                     png_uint_16 g = (png_uint_16)(((*(sp + 2)) << 8)
-                         + *(sp + 3));
-
-                     png_uint_16 b = (png_uint_16)(((*(sp + 4)) << 8)
-                         + *(sp + 5));
-
-                     if (r == png_ptr->trans_color.red &&
-                         g == png_ptr->trans_color.green &&
-                         b == png_ptr->trans_color.blue)
-                     {
-                        *sp = (png_byte)((png_ptr->background.red >> 8) & 0xff);
-                        *(sp + 1) = (png_byte)(png_ptr->background.red & 0xff);
-                        *(sp + 2) = (png_byte)((png_ptr->background.green >> 8)
-                                & 0xff);
-                        *(sp + 3) = (png_byte)(png_ptr->background.green
-                                & 0xff);
-                        *(sp + 4) = (png_byte)((png_ptr->background.blue >> 8)
-                                & 0xff);
-                        *(sp + 5) = (png_byte)(png_ptr->background.blue & 0xff);
-                     }
-                  }
-               }
-            }
-            break;
-         }
-
-         case PNG_COLOR_TYPE_GRAY_ALPHA:
-         {
-            if (row_info->bit_depth == 8)
-            {
-#ifdef PNG_READ_GAMMA_SUPPORTED
-               if (gamma_to_1 != NULL && gamma_from_1 != NULL &&
-                   gamma_table != NULL)
-               {
-                  sp = row;
-                  for (i = 0; i < row_width; i++, sp += 2)
-                  {
-                     png_uint_16 a = *(sp + 1);
-
-                     if (a == 0xff)
-                        *sp = gamma_table[*sp];
-
-                     else if (a == 0)
-                     {
-                        /* Background is already in screen gamma */
-                        *sp = (png_byte)png_ptr->background.gray;
-                     }
-
-                     else
-                     {
-                        png_byte v, w;
-
-                        v = gamma_to_1[*sp];
-                        png_composite(w, v, a, png_ptr->background_1.gray);
-                        if (!optimize)
-                           w = gamma_from_1[w];
-                        *sp = w;
-                     }
-                  }
-               }
-               else
-#endif
-               {
-                  sp = row;
-                  for (i = 0; i < row_width; i++, sp += 2)
-                  {
-                     png_byte a = *(sp + 1);
-
-                     if (a == 0)
-                        *sp = (png_byte)png_ptr->background.gray;
-
-                     else if (a < 0xff)
-                        png_composite(*sp, *sp, a, png_ptr->background_1.gray);
-                  }
-               }
-            }
-            else /* if (png_ptr->bit_depth == 16) */
-            {
-#ifdef PNG_READ_GAMMA_SUPPORTED
-               if (gamma_16 != NULL && gamma_16_from_1 != NULL &&
-                   gamma_16_to_1 != NULL)
-               {
-                  sp = row;
-                  for (i = 0; i < row_width; i++, sp += 4)
-                  {
-                     png_uint_16 a = (png_uint_16)(((*(sp + 2)) << 8)
-                         + *(sp + 3));
-
-                     if (a == (png_uint_16)0xffff)
-                     {
-                        png_uint_16 v;
-
-                        v = gamma_16[*(sp + 1) >> gamma_shift][*sp];
-                        *sp = (png_byte)((v >> 8) & 0xff);
-                        *(sp + 1) = (png_byte)(v & 0xff);
-                     }
-
-                     else if (a == 0)
-                     {
-                        /* Background is already in screen gamma */
-                        *sp = (png_byte)((png_ptr->background.gray >> 8)
-                                & 0xff);
-                        *(sp + 1) = (png_byte)(png_ptr->background.gray & 0xff);
-                     }
-
-                     else
-                     {
-                        png_uint_16 g, v, w;
-
-                        g = gamma_16_to_1[*(sp + 1) >> gamma_shift][*sp];
-                        png_composite_16(v, g, a, png_ptr->background_1.gray);
-                        if (optimize)
-                           w = v;
-                        else
-                           w = gamma_16_from_1[(v&0xff) >> gamma_shift][v >> 8];
-                        *sp = (png_byte)((w >> 8) & 0xff);
-                        *(sp + 1) = (png_byte)(w & 0xff);
-                     }
-                  }
-               }
-               else
-#endif
-               {
-                  sp = row;
-                  for (i = 0; i < row_width; i++, sp += 4)
-                  {
-                     png_uint_16 a = (png_uint_16)(((*(sp + 2)) << 8)
-                         + *(sp + 3));
-
-                     if (a == 0)
-                     {
-                        *sp = (png_byte)((png_ptr->background.gray >> 8)
-                                & 0xff);
-                        *(sp + 1) = (png_byte)(png_ptr->background.gray & 0xff);
-                     }
-
-                     else if (a < 0xffff)
-                     {
-                        png_uint_16 g, v;
-
-                        g = (png_uint_16)(((*sp) << 8) + *(sp + 1));
-                        png_composite_16(v, g, a, png_ptr->background_1.gray);
-                        *sp = (png_byte)((v >> 8) & 0xff);
-                        *(sp + 1) = (png_byte)(v & 0xff);
-                     }
-                  }
-               }
-            }
-            break;
-         }
-
-         case PNG_COLOR_TYPE_RGB_ALPHA:
-         {
-            if (row_info->bit_depth == 8)
-            {
-#ifdef PNG_READ_GAMMA_SUPPORTED
-               if (gamma_to_1 != NULL && gamma_from_1 != NULL &&
-                   gamma_table != NULL)
-               {
-                  sp = row;
-                  for (i = 0; i < row_width; i++, sp += 4)
-                  {
-                     png_byte a = *(sp + 3);
-
-                     if (a == 0xff)
-                     {
-                        *sp = gamma_table[*sp];
-                        *(sp + 1) = gamma_table[*(sp + 1)];
-                        *(sp + 2) = gamma_table[*(sp + 2)];
-                     }
-
-                     else if (a == 0)
-                     {
-                        /* Background is already in screen gamma */
-                        *sp = (png_byte)png_ptr->background.red;
-                        *(sp + 1) = (png_byte)png_ptr->background.green;
-                        *(sp + 2) = (png_byte)png_ptr->background.blue;
-                     }
-
-                     else
-                     {
-                        png_byte v, w;
-
-                        v = gamma_to_1[*sp];
-                        png_composite(w, v, a, png_ptr->background_1.red);
-                        if (!optimize) w = gamma_from_1[w];
-                        *sp = w;
-
-                        v = gamma_to_1[*(sp + 1)];
-                        png_composite(w, v, a, png_ptr->background_1.green);
-                        if (!optimize) w = gamma_from_1[w];
-                        *(sp + 1) = w;
-
-                        v = gamma_to_1[*(sp + 2)];
-                        png_composite(w, v, a, png_ptr->background_1.blue);
-                        if (!optimize) w = gamma_from_1[w];
-                        *(sp + 2) = w;
-                     }
-                  }
-               }
-               else
-#endif
-               {
-                  sp = row;
-                  for (i = 0; i < row_width; i++, sp += 4)
-                  {
-                     png_byte a = *(sp + 3);
-
-                     if (a == 0)
-                     {
-                        *sp = (png_byte)png_ptr->background.red;
-                        *(sp + 1) = (png_byte)png_ptr->background.green;
-                        *(sp + 2) = (png_byte)png_ptr->background.blue;
-                     }
-
-                     else if (a < 0xff)
-                     {
-                        png_composite(*sp, *sp, a, png_ptr->background.red);
-
-                        png_composite(*(sp + 1), *(sp + 1), a,
-                            png_ptr->background.green);
-
-                        png_composite(*(sp + 2), *(sp + 2), a,
-                            png_ptr->background.blue);
-                     }
-                  }
-               }
-            }
-            else /* if (row_info->bit_depth == 16) */
-            {
-#ifdef PNG_READ_GAMMA_SUPPORTED
-               if (gamma_16 != NULL && gamma_16_from_1 != NULL &&
-                   gamma_16_to_1 != NULL)
-               {
-                  sp = row;
-                  for (i = 0; i < row_width; i++, sp += 8)
-                  {
-                     png_uint_16 a = (png_uint_16)(((png_uint_16)(*(sp + 6))
-                         << 8) + (png_uint_16)(*(sp + 7)));
-
-                     if (a == (png_uint_16)0xffff)
-                     {
-                        png_uint_16 v;
-
-                        v = gamma_16[*(sp + 1) >> gamma_shift][*sp];
-                        *sp = (png_byte)((v >> 8) & 0xff);
-                        *(sp + 1) = (png_byte)(v & 0xff);
-
-                        v = gamma_16[*(sp + 3) >> gamma_shift][*(sp + 2)];
-                        *(sp + 2) = (png_byte)((v >> 8) & 0xff);
-                        *(sp + 3) = (png_byte)(v & 0xff);
-
-                        v = gamma_16[*(sp + 5) >> gamma_shift][*(sp + 4)];
-                        *(sp + 4) = (png_byte)((v >> 8) & 0xff);
-                        *(sp + 5) = (png_byte)(v & 0xff);
-                     }
-
-                     else if (a == 0)
-                     {
-                        /* Background is already in screen gamma */
-                        *sp = (png_byte)((png_ptr->background.red >> 8) & 0xff);
-                        *(sp + 1) = (png_byte)(png_ptr->background.red & 0xff);
-                        *(sp + 2) = (png_byte)((png_ptr->background.green >> 8)
-                                & 0xff);
-                        *(sp + 3) = (png_byte)(png_ptr->background.green
-                                & 0xff);
-                        *(sp + 4) = (png_byte)((png_ptr->background.blue >> 8)
-                                & 0xff);
-                        *(sp + 5) = (png_byte)(png_ptr->background.blue & 0xff);
-                     }
-
-                     else
-                     {
-                        png_uint_16 v, w;
-
-                        v = gamma_16_to_1[*(sp + 1) >> gamma_shift][*sp];
-                        png_composite_16(w, v, a, png_ptr->background_1.red);
-                        if (!optimize)
-                           w = gamma_16_from_1[((w&0xff) >> gamma_shift)]
-                               [w >> 8];
-                        *sp = (png_byte)((w >> 8) & 0xff);
-                        *(sp + 1) = (png_byte)(w & 0xff);
-
-                        v = gamma_16_to_1[*(sp + 3) >> gamma_shift][*(sp + 2)];
-                        png_composite_16(w, v, a, png_ptr->background_1.green);
-                        if (!optimize)
-                           w = gamma_16_from_1[((w&0xff) >> gamma_shift)]
-                               [w >> 8];
-
-                        *(sp + 2) = (png_byte)((w >> 8) & 0xff);
-                        *(sp + 3) = (png_byte)(w & 0xff);
-
-                        v = gamma_16_to_1[*(sp + 5) >> gamma_shift][*(sp + 4)];
-                        png_composite_16(w, v, a, png_ptr->background_1.blue);
-                        if (!optimize)
-                           w = gamma_16_from_1[((w&0xff) >> gamma_shift)]
-                               [w >> 8];
-
-                        *(sp + 4) = (png_byte)((w >> 8) & 0xff);
-                        *(sp + 5) = (png_byte)(w & 0xff);
-                     }
-                  }
-               }
-
-               else
-#endif
-               {
-                  sp = row;
-                  for (i = 0; i < row_width; i++, sp += 8)
-                  {
-                     png_uint_16 a = (png_uint_16)(((png_uint_16)(*(sp + 6))
-                         << 8) + (png_uint_16)(*(sp + 7)));
-
-                     if (a == 0)
-                     {
-                        *sp = (png_byte)((png_ptr->background.red >> 8) & 0xff);
-                        *(sp + 1) = (png_byte)(png_ptr->background.red & 0xff);
-                        *(sp + 2) = (png_byte)((png_ptr->background.green >> 8)
-                                & 0xff);
-                        *(sp + 3) = (png_byte)(png_ptr->background.green
-                                & 0xff);
-                        *(sp + 4) = (png_byte)((png_ptr->background.blue >> 8)
-                                & 0xff);
-                        *(sp + 5) = (png_byte)(png_ptr->background.blue & 0xff);
-                     }
-
-                     else if (a < 0xffff)
-                     {
-                        png_uint_16 v;
-
-                        png_uint_16 r = (png_uint_16)(((*sp) << 8) + *(sp + 1));
-                        png_uint_16 g = (png_uint_16)(((*(sp + 2)) << 8)
-                            + *(sp + 3));
-                        png_uint_16 b = (png_uint_16)(((*(sp + 4)) << 8)
-                            + *(sp + 5));
-
-                        png_composite_16(v, r, a, png_ptr->background.red);
-                        *sp = (png_byte)((v >> 8) & 0xff);
-                        *(sp + 1) = (png_byte)(v & 0xff);
-
-                        png_composite_16(v, g, a, png_ptr->background.green);
-                        *(sp + 2) = (png_byte)((v >> 8) & 0xff);
-                        *(sp + 3) = (png_byte)(v & 0xff);
-
-                        png_composite_16(v, b, a, png_ptr->background.blue);
-                        *(sp + 4) = (png_byte)((v >> 8) & 0xff);
-                        *(sp + 5) = (png_byte)(v & 0xff);
-                     }
-                  }
-               }
-            }
-            break;
-         }
-
-         default:
-            break;
-      }
-   }
-}
-#endif /* PNG_READ_BACKGROUND_SUPPORTED || PNG_READ_ALPHA_MODE_SUPPORTED */
-
-#ifdef PNG_READ_GAMMA_SUPPORTED
-/* Gamma correct the image, avoiding the alpha channel.  Make sure
- * you do this after you deal with the transparency issue on grayscale
- * or RGB images. If your bit depth is 8, use gamma_table, if it
- * is 16, use gamma_16_table and gamma_shift.  Build these with
- * build_gamma_table().
- */
-void /* PRIVATE */
-png_do_gamma(png_row_infop row_info, png_bytep row, png_structp png_ptr)
-{
-   png_const_bytep gamma_table = png_ptr->gamma_table;
-   png_const_uint_16pp gamma_16_table = png_ptr->gamma_16_table;
-   int gamma_shift = png_ptr->gamma_shift;
-
-   png_bytep sp;
-   png_uint_32 i;
-   png_uint_32 row_width=row_info->width;
-
-   png_debug(1, "in png_do_gamma");
-
-   if (((row_info->bit_depth <= 8 && gamma_table != NULL) ||
-       (row_info->bit_depth == 16 && gamma_16_table != NULL)))
-   {
-      switch (row_info->color_type)
-      {
-         case PNG_COLOR_TYPE_RGB:
-         {
-            if (row_info->bit_depth == 8)
-            {
-               sp = row;
-               for (i = 0; i < row_width; i++)
-               {
-                  *sp = gamma_table[*sp];
-                  sp++;
-                  *sp = gamma_table[*sp];
-                  sp++;
-                  *sp = gamma_table[*sp];
-                  sp++;
-               }
-            }
-
-            else /* if (row_info->bit_depth == 16) */
-            {
-               sp = row;
-               for (i = 0; i < row_width; i++)
-               {
-                  png_uint_16 v;
-
-                  v = gamma_16_table[*(sp + 1) >> gamma_shift][*sp];
-                  *sp = (png_byte)((v >> 8) & 0xff);
-                  *(sp + 1) = (png_byte)(v & 0xff);
-                  sp += 2;
-
-                  v = gamma_16_table[*(sp + 1) >> gamma_shift][*sp];
-                  *sp = (png_byte)((v >> 8) & 0xff);
-                  *(sp + 1) = (png_byte)(v & 0xff);
-                  sp += 2;
-
-                  v = gamma_16_table[*(sp + 1) >> gamma_shift][*sp];
-                  *sp = (png_byte)((v >> 8) & 0xff);
-                  *(sp + 1) = (png_byte)(v & 0xff);
-                  sp += 2;
-               }
-            }
-            break;
-         }
-
-         case PNG_COLOR_TYPE_RGB_ALPHA:
-         {
-            if (row_info->bit_depth == 8)
-            {
-               sp = row;
-               for (i = 0; i < row_width; i++)
-               {
-                  *sp = gamma_table[*sp];
-                  sp++;
-
-                  *sp = gamma_table[*sp];
-                  sp++;
-
-                  *sp = gamma_table[*sp];
-                  sp++;
-
-                  sp++;
-               }
-            }
-
-            else /* if (row_info->bit_depth == 16) */
-            {
-               sp = row;
-               for (i = 0; i < row_width; i++)
-               {
-                  png_uint_16 v = gamma_16_table[*(sp + 1) >> gamma_shift][*sp];
-                  *sp = (png_byte)((v >> 8) & 0xff);
-                  *(sp + 1) = (png_byte)(v & 0xff);
-                  sp += 2;
-
-                  v = gamma_16_table[*(sp + 1) >> gamma_shift][*sp];
-                  *sp = (png_byte)((v >> 8) & 0xff);
-                  *(sp + 1) = (png_byte)(v & 0xff);
-                  sp += 2;
-
-                  v = gamma_16_table[*(sp + 1) >> gamma_shift][*sp];
-                  *sp = (png_byte)((v >> 8) & 0xff);
-                  *(sp + 1) = (png_byte)(v & 0xff);
-                  sp += 4;
-               }
-            }
-            break;
-         }
-
-         case PNG_COLOR_TYPE_GRAY_ALPHA:
-         {
-            if (row_info->bit_depth == 8)
-            {
-               sp = row;
-               for (i = 0; i < row_width; i++)
-               {
-                  *sp = gamma_table[*sp];
-                  sp += 2;
-               }
-            }
-
-            else /* if (row_info->bit_depth == 16) */
-            {
-               sp = row;
-               for (i = 0; i < row_width; i++)
-               {
-                  png_uint_16 v = gamma_16_table[*(sp + 1) >> gamma_shift][*sp];
-                  *sp = (png_byte)((v >> 8) & 0xff);
-                  *(sp + 1) = (png_byte)(v & 0xff);
-                  sp += 4;
-               }
-            }
-            break;
-         }
-
-         case PNG_COLOR_TYPE_GRAY:
-         {
-            if (row_info->bit_depth == 2)
-            {
-               sp = row;
-               for (i = 0; i < row_width; i += 4)
-               {
-                  int a = *sp & 0xc0;
-                  int b = *sp & 0x30;
-                  int c = *sp & 0x0c;
-                  int d = *sp & 0x03;
-
-                  *sp = (png_byte)(
-                      ((((int)gamma_table[a|(a>>2)|(a>>4)|(a>>6)])   ) & 0xc0)|
-                      ((((int)gamma_table[(b<<2)|b|(b>>2)|(b>>4)])>>2) & 0x30)|
-                      ((((int)gamma_table[(c<<4)|(c<<2)|c|(c>>2)])>>4) & 0x0c)|
-                      ((((int)gamma_table[(d<<6)|(d<<4)|(d<<2)|d])>>6) ));
-                  sp++;
-               }
-            }
-
-            if (row_info->bit_depth == 4)
-            {
-               sp = row;
-               for (i = 0; i < row_width; i += 2)
-               {
-                  int msb = *sp & 0xf0;
-                  int lsb = *sp & 0x0f;
-
-                  *sp = (png_byte)((((int)gamma_table[msb | (msb >> 4)]) & 0xf0)
-                      | (((int)gamma_table[(lsb << 4) | lsb]) >> 4));
-                  sp++;
-               }
-            }
-
-            else if (row_info->bit_depth == 8)
-            {
-               sp = row;
-               for (i = 0; i < row_width; i++)
-               {
-                  *sp = gamma_table[*sp];
-                  sp++;
-               }
-            }
-
-            else if (row_info->bit_depth == 16)
-            {
-               sp = row;
-               for (i = 0; i < row_width; i++)
-               {
-                  png_uint_16 v = gamma_16_table[*(sp + 1) >> gamma_shift][*sp];
-                  *sp = (png_byte)((v >> 8) & 0xff);
-                  *(sp + 1) = (png_byte)(v & 0xff);
-                  sp += 2;
-               }
-            }
-            break;
-         }
-
-         default:
-            break;
-      }
-   }
-}
-#endif
-
-#ifdef PNG_READ_ALPHA_MODE_SUPPORTED
-/* Encode the alpha channel to the output gamma (the input channel is always
- * linear.)  Called only with color types that have an alpha channel.  Needs the
- * from_1 tables.
- */
-void /* PRIVATE */
-png_do_encode_alpha(png_row_infop row_info, png_bytep row, png_structp png_ptr)
-{
-   png_uint_32 row_width = row_info->width;
-
-   png_debug(1, "in png_do_encode_alpha");
-
-   if (row_info->color_type & PNG_COLOR_MASK_ALPHA)
-   {
-      if (row_info->bit_depth == 8)
-      {
-         PNG_CONST png_bytep table = png_ptr->gamma_from_1;
-
-         if (table != NULL)
-         {
-            PNG_CONST int step =
-               (row_info->color_type & PNG_COLOR_MASK_COLOR) ? 4 : 2;
-
-            /* The alpha channel is the last component: */
-            row += step - 1;
-
-            for (; row_width > 0; --row_width, row += step)
-               *row = table[*row];
-
-            return;
-         }
-      }
-
-      else if (row_info->bit_depth == 16)
-      {
-         PNG_CONST png_uint_16pp table = png_ptr->gamma_16_from_1;
-         PNG_CONST int gamma_shift = png_ptr->gamma_shift;
-
-         if (table != NULL)
-         {
-            PNG_CONST int step =
-               (row_info->color_type & PNG_COLOR_MASK_COLOR) ? 8 : 4;
-
-            /* The alpha channel is the last component: */
-            row += step - 2;
-
-            for (; row_width > 0; --row_width, row += step)
-            {
-               png_uint_16 v;
-
-               v = table[*(row + 1) >> gamma_shift][*row];
-               *row = (png_byte)((v >> 8) & 0xff);
-               *(row + 1) = (png_byte)(v & 0xff);
-            }
-
-            return;
-         }
-      }
-   }
-
-   /* Only get to here if called with a weird row_info; no harm has been done,
-    * so just issue a warning.
-    */
-   png_warning(png_ptr, "png_do_encode_alpha: unexpected call");
-}
-#endif
-
-#ifdef PNG_READ_EXPAND_SUPPORTED
-/* Expands a palette row to an RGB or RGBA row depending
- * upon whether you supply trans and num_trans.
- */
-void /* PRIVATE */
-png_do_expand_palette(png_row_infop row_info, png_bytep row,
-   png_const_colorp palette, png_const_bytep trans_alpha, int num_trans)
-{
-   int shift, value;
-   png_bytep sp, dp;
-   png_uint_32 i;
-   png_uint_32 row_width=row_info->width;
-
-   png_debug(1, "in png_do_expand_palette");
-
-   if (row_info->color_type == PNG_COLOR_TYPE_PALETTE)
-   {
-      if (row_info->bit_depth < 8)
-      {
-         switch (row_info->bit_depth)
-         {
-            case 1:
-            {
-               sp = row + (png_size_t)((row_width - 1) >> 3);
-               dp = row + (png_size_t)row_width - 1;
-               shift = 7 - (int)((row_width + 7) & 0x07);
-               for (i = 0; i < row_width; i++)
-               {
-                  if ((*sp >> shift) & 0x01)
-                     *dp = 1;
-
-                  else
-                     *dp = 0;
-
-                  if (shift == 7)
-                  {
-                     shift = 0;
-                     sp--;
-                  }
-
-                  else
-                     shift++;
-
-                  dp--;
-               }
-               break;
-            }
-
-            case 2:
-            {
-               sp = row + (png_size_t)((row_width - 1) >> 2);
-               dp = row + (png_size_t)row_width - 1;
-               shift = (int)((3 - ((row_width + 3) & 0x03)) << 1);
-               for (i = 0; i < row_width; i++)
-               {
-                  value = (*sp >> shift) & 0x03;
-                  *dp = (png_byte)value;
-                  if (shift == 6)
-                  {
-                     shift = 0;
-                     sp--;
-                  }
-
-                  else
-                     shift += 2;
-
-                  dp--;
-               }
-               break;
-            }
-
-            case 4:
-            {
-               sp = row + (png_size_t)((row_width - 1) >> 1);
-               dp = row + (png_size_t)row_width - 1;
-               shift = (int)((row_width & 0x01) << 2);
-               for (i = 0; i < row_width; i++)
-               {
-                  value = (*sp >> shift) & 0x0f;
-                  *dp = (png_byte)value;
-                  if (shift == 4)
-                  {
-                     shift = 0;
-                     sp--;
-                  }
-
-                  else
-                     shift += 4;
-
-                  dp--;
-               }
-               break;
-            }
-
-            default:
-               break;
-         }
-         row_info->bit_depth = 8;
-         row_info->pixel_depth = 8;
-         row_info->rowbytes = row_width;
-      }
-
-      if (row_info->bit_depth == 8)
-      {
-         {
-            if (num_trans > 0)
-            {
-               sp = row + (png_size_t)row_width - 1;
-               dp = row + (png_size_t)(row_width << 2) - 1;
-
-               for (i = 0; i < row_width; i++)
-               {
-                  if ((int)(*sp) >= num_trans)
-                     *dp-- = 0xff;
-
-                  else
-                     *dp-- = trans_alpha[*sp];
-
-                  *dp-- = palette[*sp].blue;
-                  *dp-- = palette[*sp].green;
-                  *dp-- = palette[*sp].red;
-                  sp--;
-               }
-               row_info->bit_depth = 8;
-               row_info->pixel_depth = 32;
-               row_info->rowbytes = row_width * 4;
-               row_info->color_type = 6;
-               row_info->channels = 4;
-            }
-
-            else
-            {
-               sp = row + (png_size_t)row_width - 1;
-               dp = row + (png_size_t)(row_width * 3) - 1;
-
-               for (i = 0; i < row_width; i++)
-               {
-                  *dp-- = palette[*sp].blue;
-                  *dp-- = palette[*sp].green;
-                  *dp-- = palette[*sp].red;
-                  sp--;
-               }
-
-               row_info->bit_depth = 8;
-               row_info->pixel_depth = 24;
-               row_info->rowbytes = row_width * 3;
-               row_info->color_type = 2;
-               row_info->channels = 3;
-            }
-         }
-      }
-   }
-}
-
-/* If the bit depth < 8, it is expanded to 8.  Also, if the already
- * expanded transparency value is supplied, an alpha channel is built.
- */
-void /* PRIVATE */
-png_do_expand(png_row_infop row_info, png_bytep row,
-    png_const_color_16p trans_color)
-{
-   int shift, value;
-   png_bytep sp, dp;
-   png_uint_32 i;
-   png_uint_32 row_width=row_info->width;
-
-   png_debug(1, "in png_do_expand");
-
-   {
-      if (row_info->color_type == PNG_COLOR_TYPE_GRAY)
-      {
-         png_uint_16 gray = (png_uint_16)(trans_color ? trans_color->gray : 0);
-
-         if (row_info->bit_depth < 8)
-         {
-            switch (row_info->bit_depth)
-            {
-               case 1:
-               {
-                  gray = (png_uint_16)((gray & 0x01) * 0xff);
-                  sp = row + (png_size_t)((row_width - 1) >> 3);
-                  dp = row + (png_size_t)row_width - 1;
-                  shift = 7 - (int)((row_width + 7) & 0x07);
-                  for (i = 0; i < row_width; i++)
-                  {
-                     if ((*sp >> shift) & 0x01)
-                        *dp = 0xff;
-
-                     else
-                        *dp = 0;
-
-                     if (shift == 7)
-                     {
-                        shift = 0;
-                        sp--;
-                     }
-
-                     else
-                        shift++;
-
-                     dp--;
-                  }
-                  break;
-               }
-
-               case 2:
-               {
-                  gray = (png_uint_16)((gray & 0x03) * 0x55);
-                  sp = row + (png_size_t)((row_width - 1) >> 2);
-                  dp = row + (png_size_t)row_width - 1;
-                  shift = (int)((3 - ((row_width + 3) & 0x03)) << 1);
-                  for (i = 0; i < row_width; i++)
-                  {
-                     value = (*sp >> shift) & 0x03;
-                     *dp = (png_byte)(value | (value << 2) | (value << 4) |
-                        (value << 6));
-                     if (shift == 6)
-                     {
-                        shift = 0;
-                        sp--;
-                     }
-
-                     else
-                        shift += 2;
-
-                     dp--;
-                  }
-                  break;
-               }
-
-               case 4:
-               {
-                  gray = (png_uint_16)((gray & 0x0f) * 0x11);
-                  sp = row + (png_size_t)((row_width - 1) >> 1);
-                  dp = row + (png_size_t)row_width - 1;
-                  shift = (int)((1 - ((row_width + 1) & 0x01)) << 2);
-                  for (i = 0; i < row_width; i++)
-                  {
-                     value = (*sp >> shift) & 0x0f;
-                     *dp = (png_byte)(value | (value << 4));
-                     if (shift == 4)
-                     {
-                        shift = 0;
-                        sp--;
-                     }
-
-                     else
-                        shift = 4;
-
-                     dp--;
-                  }
-                  break;
-               }
-
-               default:
-                  break;
-            }
-
-            row_info->bit_depth = 8;
-            row_info->pixel_depth = 8;
-            row_info->rowbytes = row_width;
-         }
-
-         if (trans_color != NULL)
-         {
-            if (row_info->bit_depth == 8)
-            {
-               gray = gray & 0xff;
-               sp = row + (png_size_t)row_width - 1;
-               dp = row + (png_size_t)(row_width << 1) - 1;
-
-               for (i = 0; i < row_width; i++)
-               {
-                  if (*sp == gray)
-                     *dp-- = 0;
-
-                  else
-                     *dp-- = 0xff;
-
-                  *dp-- = *sp--;
-               }
-            }
-
-            else if (row_info->bit_depth == 16)
-            {
-               png_byte gray_high = (png_byte)((gray >> 8) & 0xff);
-               png_byte gray_low = (png_byte)(gray & 0xff);
-               sp = row + row_info->rowbytes - 1;
-               dp = row + (row_info->rowbytes << 1) - 1;
-               for (i = 0; i < row_width; i++)
-               {
-                  if (*(sp - 1) == gray_high && *(sp) == gray_low)
-                  {
-                     *dp-- = 0;
-                     *dp-- = 0;
-                  }
-
-                  else
-                  {
-                     *dp-- = 0xff;
-                     *dp-- = 0xff;
-                  }
-
-                  *dp-- = *sp--;
-                  *dp-- = *sp--;
-               }
-            }
-
-            row_info->color_type = PNG_COLOR_TYPE_GRAY_ALPHA;
-            row_info->channels = 2;
-            row_info->pixel_depth = (png_byte)(row_info->bit_depth << 1);
-            row_info->rowbytes = PNG_ROWBYTES(row_info->pixel_depth,
-               row_width);
-         }
-      }
-      else if (row_info->color_type == PNG_COLOR_TYPE_RGB && trans_color)
-      {
-         if (row_info->bit_depth == 8)
-         {
-            png_byte red = (png_byte)(trans_color->red & 0xff);
-            png_byte green = (png_byte)(trans_color->green & 0xff);
-            png_byte blue = (png_byte)(trans_color->blue & 0xff);
-            sp = row + (png_size_t)row_info->rowbytes - 1;
-            dp = row + (png_size_t)(row_width << 2) - 1;
-            for (i = 0; i < row_width; i++)
-            {
-               if (*(sp - 2) == red && *(sp - 1) == green && *(sp) == blue)
-                  *dp-- = 0;
-
-               else
-                  *dp-- = 0xff;
-
-               *dp-- = *sp--;
-               *dp-- = *sp--;
-               *dp-- = *sp--;
-            }
-         }
-         else if (row_info->bit_depth == 16)
-         {
-            png_byte red_high = (png_byte)((trans_color->red >> 8) & 0xff);
-            png_byte green_high = (png_byte)((trans_color->green >> 8) & 0xff);
-            png_byte blue_high = (png_byte)((trans_color->blue >> 8) & 0xff);
-            png_byte red_low = (png_byte)(trans_color->red & 0xff);
-            png_byte green_low = (png_byte)(trans_color->green & 0xff);
-            png_byte blue_low = (png_byte)(trans_color->blue & 0xff);
-            sp = row + row_info->rowbytes - 1;
-            dp = row + (png_size_t)(row_width << 3) - 1;
-            for (i = 0; i < row_width; i++)
-            {
-               if (*(sp - 5) == red_high &&
-                   *(sp - 4) == red_low &&
-                   *(sp - 3) == green_high &&
-                   *(sp - 2) == green_low &&
-                   *(sp - 1) == blue_high &&
-                   *(sp    ) == blue_low)
-               {
-                  *dp-- = 0;
-                  *dp-- = 0;
-               }
-
-               else
-               {
-                  *dp-- = 0xff;
-                  *dp-- = 0xff;
-               }
-
-               *dp-- = *sp--;
-               *dp-- = *sp--;
-               *dp-- = *sp--;
-               *dp-- = *sp--;
-               *dp-- = *sp--;
-               *dp-- = *sp--;
-            }
-         }
-         row_info->color_type = PNG_COLOR_TYPE_RGB_ALPHA;
-         row_info->channels = 4;
-         row_info->pixel_depth = (png_byte)(row_info->bit_depth << 2);
-         row_info->rowbytes = PNG_ROWBYTES(row_info->pixel_depth, row_width);
-      }
-   }
-}
-#endif
-
-#ifdef PNG_READ_EXPAND_16_SUPPORTED
-/* If the bit depth is 8 and the color type is not a palette type expand the
- * whole row to 16 bits.  Has no effect otherwise.
- */
-void /* PRIVATE */
-png_do_expand_16(png_row_infop row_info, png_bytep row)
-{
-   if (row_info->bit_depth == 8 &&
-      row_info->color_type != PNG_COLOR_TYPE_PALETTE)
-   {
-      /* The row have a sequence of bytes containing [0..255] and we need
-       * to turn it into another row containing [0..65535], to do this we
-       * calculate:
-       *
-       *  (input / 255) * 65535
-       *
-       *  Which happens to be exactly input * 257 and this can be achieved
-       *  simply by byte replication in place (copying backwards).
-       */
-      png_byte *sp = row + row_info->rowbytes; /* source, last byte + 1 */
-      png_byte *dp = sp + row_info->rowbytes;  /* destination, end + 1 */
-      while (dp > sp)
-         dp[-2] = dp[-1] = *--sp, dp -= 2;
-
-      row_info->rowbytes *= 2;
-      row_info->bit_depth = 16;
-      row_info->pixel_depth = (png_byte)(row_info->channels * 16);
-   }
-}
-#endif
-
-#ifdef PNG_READ_QUANTIZE_SUPPORTED
-void /* PRIVATE */
-png_do_quantize(png_row_infop row_info, png_bytep row,
-    png_const_bytep palette_lookup, png_const_bytep quantize_lookup)
-{
-   png_bytep sp, dp;
-   png_uint_32 i;
-   png_uint_32 row_width=row_info->width;
-
-   png_debug(1, "in png_do_quantize");
-
-   if (row_info->bit_depth == 8)
-   {
-      if (row_info->color_type == PNG_COLOR_TYPE_RGB && palette_lookup)
-      {
-         int r, g, b, p;
-         sp = row;
-         dp = row;
-         for (i = 0; i < row_width; i++)
-         {
-            r = *sp++;
-            g = *sp++;
-            b = *sp++;
-
-            /* This looks real messy, but the compiler will reduce
-             * it down to a reasonable formula.  For example, with
-             * 5 bits per color, we get:
-             * p = (((r >> 3) & 0x1f) << 10) |
-             *    (((g >> 3) & 0x1f) << 5) |
-             *    ((b >> 3) & 0x1f);
-             */
-            p = (((r >> (8 - PNG_QUANTIZE_RED_BITS)) &
-                ((1 << PNG_QUANTIZE_RED_BITS) - 1)) <<
-                (PNG_QUANTIZE_GREEN_BITS + PNG_QUANTIZE_BLUE_BITS)) |
-                (((g >> (8 - PNG_QUANTIZE_GREEN_BITS)) &
-                ((1 << PNG_QUANTIZE_GREEN_BITS) - 1)) <<
-                (PNG_QUANTIZE_BLUE_BITS)) |
-                ((b >> (8 - PNG_QUANTIZE_BLUE_BITS)) &
-                ((1 << PNG_QUANTIZE_BLUE_BITS) - 1));
-
-            *dp++ = palette_lookup[p];
-         }
-
-         row_info->color_type = PNG_COLOR_TYPE_PALETTE;
-         row_info->channels = 1;
-         row_info->pixel_depth = row_info->bit_depth;
-         row_info->rowbytes = PNG_ROWBYTES(row_info->pixel_depth, row_width);
-      }
-
-      else if (row_info->color_type == PNG_COLOR_TYPE_RGB_ALPHA &&
-         palette_lookup != NULL)
-      {
-         int r, g, b, p;
-         sp = row;
-         dp = row;
-         for (i = 0; i < row_width; i++)
-         {
-            r = *sp++;
-            g = *sp++;
-            b = *sp++;
-            sp++;
-
-            p = (((r >> (8 - PNG_QUANTIZE_RED_BITS)) &
-                ((1 << PNG_QUANTIZE_RED_BITS) - 1)) <<
-                (PNG_QUANTIZE_GREEN_BITS + PNG_QUANTIZE_BLUE_BITS)) |
-                (((g >> (8 - PNG_QUANTIZE_GREEN_BITS)) &
-                ((1 << PNG_QUANTIZE_GREEN_BITS) - 1)) <<
-                (PNG_QUANTIZE_BLUE_BITS)) |
-                ((b >> (8 - PNG_QUANTIZE_BLUE_BITS)) &
-                ((1 << PNG_QUANTIZE_BLUE_BITS) - 1));
-
-            *dp++ = palette_lookup[p];
-         }
-
-         row_info->color_type = PNG_COLOR_TYPE_PALETTE;
-         row_info->channels = 1;
-         row_info->pixel_depth = row_info->bit_depth;
-         row_info->rowbytes = PNG_ROWBYTES(row_info->pixel_depth, row_width);
-      }
-
-      else if (row_info->color_type == PNG_COLOR_TYPE_PALETTE &&
-         quantize_lookup)
-      {
-         sp = row;
-
-         for (i = 0; i < row_width; i++, sp++)
-         {
-            *sp = quantize_lookup[*sp];
-         }
-      }
-   }
-}
-#endif /* PNG_READ_QUANTIZE_SUPPORTED */
-#endif /* PNG_READ_TRANSFORMS_SUPPORTED */
-
-#ifdef PNG_MNG_FEATURES_SUPPORTED
-/* Undoes intrapixel differencing  */
-void /* PRIVATE */
-png_do_read_intrapixel(png_row_infop row_info, png_bytep row)
-{
-   png_debug(1, "in png_do_read_intrapixel");
-
-   if (
-       (row_info->color_type & PNG_COLOR_MASK_COLOR))
-   {
-      int bytes_per_pixel;
-      png_uint_32 row_width = row_info->width;
-
-      if (row_info->bit_depth == 8)
-      {
-         png_bytep rp;
-         png_uint_32 i;
-
-         if (row_info->color_type == PNG_COLOR_TYPE_RGB)
-            bytes_per_pixel = 3;
-
-         else if (row_info->color_type == PNG_COLOR_TYPE_RGB_ALPHA)
-            bytes_per_pixel = 4;
-
-         else
-            return;
-
-         for (i = 0, rp = row; i < row_width; i++, rp += bytes_per_pixel)
-         {
-            *(rp) = (png_byte)((256 + *rp + *(rp + 1)) & 0xff);
-            *(rp+2) = (png_byte)((256 + *(rp + 2) + *(rp + 1)) & 0xff);
-         }
-      }
-      else if (row_info->bit_depth == 16)
-      {
-         png_bytep rp;
-         png_uint_32 i;
-
-         if (row_info->color_type == PNG_COLOR_TYPE_RGB)
-            bytes_per_pixel = 6;
-
-         else if (row_info->color_type == PNG_COLOR_TYPE_RGB_ALPHA)
-            bytes_per_pixel = 8;
-
-         else
-            return;
-
-         for (i = 0, rp = row; i < row_width; i++, rp += bytes_per_pixel)
-         {
-            png_uint_32 s0   = (*(rp    ) << 8) | *(rp + 1);
-            png_uint_32 s1   = (*(rp + 2) << 8) | *(rp + 3);
-            png_uint_32 s2   = (*(rp + 4) << 8) | *(rp + 5);
-            png_uint_32 red  = (s0 + s1 + 65536) & 0xffff;
-            png_uint_32 blue = (s2 + s1 + 65536) & 0xffff;
-            *(rp    ) = (png_byte)((red >> 8) & 0xff);
-            *(rp + 1) = (png_byte)(red & 0xff);
-            *(rp + 4) = (png_byte)((blue >> 8) & 0xff);
-            *(rp + 5) = (png_byte)(blue & 0xff);
-         }
-      }
-   }
-}
-#endif /* PNG_MNG_FEATURES_SUPPORTED */
-#endif /* PNG_READ_SUPPORTED */
diff --git a/plugingui/png/pngrutil.c b/plugingui/png/pngrutil.c
deleted file mode 100644
index bc79d5c..0000000
--- a/plugingui/png/pngrutil.c
+++ /dev/null
@@ -1,4159 +0,0 @@
-
-/* pngrutil.c - utilities to read a PNG file
- *
- * Last changed in libpng 1.5.10 [March 8, 2012]
- * Copyright (c) 1998-2012 Glenn Randers-Pehrson
- * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
- * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)
- *
- * This code is released under the libpng license.
- * For conditions of distribution and use, see the disclaimer
- * and license in png.h
- *
- * This file contains routines that are only called from within
- * libpng itself during the course of reading an image.
- */
-
-#include "pngpriv.h"
-
-#ifdef PNG_READ_SUPPORTED
-
-#define png_strtod(p,a,b) strtod(a,b)
-
-png_uint_32 PNGAPI
-png_get_uint_31(png_structp png_ptr, png_const_bytep buf)
-{
-   png_uint_32 uval = png_get_uint_32(buf);
-
-   if (uval > PNG_UINT_31_MAX)
-      dg_png_error(png_ptr, "PNG unsigned integer out of range");
-
-   return (uval);
-}
-
-#if defined(PNG_READ_gAMA_SUPPORTED) || defined(PNG_READ_cHRM_SUPPORTED)
-/* The following is a variation on the above for use with the fixed
- * point values used for gAMA and cHRM.  Instead of png_error it
- * issues a warning and returns (-1) - an invalid value because both
- * gAMA and cHRM use *unsigned* integers for fixed point values.
- */
-#define PNG_FIXED_ERROR (-1)
-
-static png_fixed_point /* PRIVATE */
-png_get_fixed_point(png_structp png_ptr, png_const_bytep buf)
-{
-   png_uint_32 uval = png_get_uint_32(buf);
-
-   if (uval <= PNG_UINT_31_MAX)
-      return (png_fixed_point)uval; /* known to be in range */
-
-   /* The caller can turn off the warning by passing NULL. */
-   if (png_ptr != NULL)
-      png_warning(png_ptr, "PNG fixed point integer out of range");
-
-   return PNG_FIXED_ERROR;
-}
-#endif
-
-#ifdef PNG_READ_INT_FUNCTIONS_SUPPORTED
-/* NOTE: the read macros will obscure these definitions, so that if
- * PNG_USE_READ_MACROS is set the library will not use them internally,
- * but the APIs will still be available externally.
- *
- * The parentheses around "PNGAPI function_name" in the following three
- * functions are necessary because they allow the macros to co-exist with
- * these (unused but exported) functions.
- */
-
-/* Grab an unsigned 32-bit integer from a buffer in big-endian format. */
-png_uint_32 (PNGAPI
-png_get_uint_32)(png_const_bytep buf)
-{
-   png_uint_32 uval =
-       ((png_uint_32)(*(buf    )) << 24) +
-       ((png_uint_32)(*(buf + 1)) << 16) +
-       ((png_uint_32)(*(buf + 2)) <<  8) +
-       ((png_uint_32)(*(buf + 3))      ) ;
-
-   return uval;
-}
-
-/* Grab a signed 32-bit integer from a buffer in big-endian format.  The
- * data is stored in the PNG file in two's complement format and there
- * is no guarantee that a 'png_int_32' is exactly 32 bits, therefore
- * the following code does a two's complement to native conversion.
- */
-png_int_32 (PNGAPI
-png_get_int_32)(png_const_bytep buf)
-{
-   png_uint_32 uval = png_get_uint_32(buf);
-   if ((uval & 0x80000000) == 0) /* non-negative */
-      return uval;
-
-   uval = (uval ^ 0xffffffff) + 1;  /* 2's complement: -x = ~x+1 */
-   return -(png_int_32)uval;
-}
-
-/* Grab an unsigned 16-bit integer from a buffer in big-endian format. */
-png_uint_16 (PNGAPI
-png_get_uint_16)(png_const_bytep buf)
-{
-   /* ANSI-C requires an int value to accomodate at least 16 bits so this
-    * works and allows the compiler not to worry about possible narrowing
-    * on 32 bit systems.  (Pre-ANSI systems did not make integers smaller
-    * than 16 bits either.)
-    */
-   unsigned int val =
-       ((unsigned int)(*buf) << 8) +
-       ((unsigned int)(*(buf + 1)));
-
-   return (png_uint_16)val;
-}
-
-#endif /* PNG_READ_INT_FUNCTIONS_SUPPORTED */
-
-/* Read and check the PNG file signature */
-void /* PRIVATE */
-png_read_sig(png_structp png_ptr, png_infop info_ptr)
-{
-   png_size_t num_checked, num_to_check;
-
-   /* Exit if the user application does not expect a signature. */
-   if (png_ptr->sig_bytes >= 8)
-      return;
-
-   num_checked = png_ptr->sig_bytes;
-   num_to_check = 8 - num_checked;
-
-#ifdef PNG_IO_STATE_SUPPORTED
-   png_ptr->io_state = PNG_IO_READING | PNG_IO_SIGNATURE;
-#endif
-
-   /* The signature must be serialized in a single I/O call. */
-   png_read_data(png_ptr, &(info_ptr->signature[num_checked]), num_to_check);
-   png_ptr->sig_bytes = 8;
-
-   if (dg_png_sig_cmp(info_ptr->signature, num_checked, num_to_check))
-   {
-      if (num_checked < 4 &&
-          dg_png_sig_cmp(info_ptr->signature, num_checked, num_to_check - 4))
-         dg_png_error(png_ptr, "Not a PNG file");
-      else
-         dg_png_error(png_ptr, "PNG file corrupted by ASCII conversion");
-   }
-   if (num_checked < 3)
-      png_ptr->mode |= PNG_HAVE_PNG_SIGNATURE;
-}
-
-/* Read the chunk header (length + type name).
- * Put the type name into png_ptr->chunk_name, and return the length.
- */
-png_uint_32 /* PRIVATE */
-png_read_chunk_header(png_structp png_ptr)
-{
-   png_byte buf[8];
-   png_uint_32 length;
-
-#ifdef PNG_IO_STATE_SUPPORTED
-   png_ptr->io_state = PNG_IO_READING | PNG_IO_CHUNK_HDR;
-#endif
-
-   /* Read the length and the chunk name.
-    * This must be performed in a single I/O call.
-    */
-   png_read_data(png_ptr, buf, 8);
-   length = png_get_uint_31(png_ptr, buf);
-
-   /* Put the chunk name into png_ptr->chunk_name. */
-   png_ptr->chunk_name = PNG_CHUNK_FROM_STRING(buf+4);
-
-   png_debug2(0, "Reading %lx chunk, length = %lu",
-       (unsigned long)png_ptr->chunk_name, (unsigned long)length);
-
-   /* Reset the crc and run it over the chunk name. */
-   png_reset_crc(png_ptr);
-   png_calculate_crc(png_ptr, buf + 4, 4);
-
-   /* Check to see if chunk name is valid. */
-   png_check_chunk_name(png_ptr, png_ptr->chunk_name);
-
-#ifdef PNG_IO_STATE_SUPPORTED
-   png_ptr->io_state = PNG_IO_READING | PNG_IO_CHUNK_DATA;
-#endif
-
-   return length;
-}
-
-/* Read data, and (optionally) run it through the CRC. */
-void /* PRIVATE */
-png_crc_read(png_structp png_ptr, png_bytep buf, png_size_t length)
-{
-   if (png_ptr == NULL)
-      return;
-
-   png_read_data(png_ptr, buf, length);
-   png_calculate_crc(png_ptr, buf, length);
-}
-
-/* Optionally skip data and then check the CRC.  Depending on whether we
- * are reading a ancillary or critical chunk, and how the program has set
- * things up, we may calculate the CRC on the data and print a message.
- * Returns '1' if there was a CRC error, '0' otherwise.
- */
-int /* PRIVATE */
-png_crc_finish(png_structp png_ptr, png_uint_32 skip)
-{
-   png_size_t i;
-   png_size_t istop = png_ptr->zbuf_size;
-
-   for (i = (png_size_t)skip; i > istop; i -= istop)
-   {
-      png_crc_read(png_ptr, png_ptr->zbuf, png_ptr->zbuf_size);
-   }
-
-   if (i)
-   {
-      png_crc_read(png_ptr, png_ptr->zbuf, i);
-   }
-
-   if (png_crc_error(png_ptr))
-   {
-      if (PNG_CHUNK_ANCILLIARY(png_ptr->chunk_name) ?
-          !(png_ptr->flags & PNG_FLAG_CRC_ANCILLARY_NOWARN) :
-          (png_ptr->flags & PNG_FLAG_CRC_CRITICAL_USE))
-      {
-         png_chunk_warning(png_ptr, "CRC error");
-      }
-
-      else
-      {
-         png_chunk_benign_error(png_ptr, "CRC error");
-         return (0);
-      }
-
-      return (1);
-   }
-
-   return (0);
-}
-
-/* Compare the CRC stored in the PNG file with that calculated by libpng from
- * the data it has read thus far.
- */
-int /* PRIVATE */
-png_crc_error(png_structp png_ptr)
-{
-   png_byte crc_bytes[4];
-   png_uint_32 crc;
-   int need_crc = 1;
-
-   if (PNG_CHUNK_ANCILLIARY(png_ptr->chunk_name))
-   {
-      if ((png_ptr->flags & PNG_FLAG_CRC_ANCILLARY_MASK) ==
-          (PNG_FLAG_CRC_ANCILLARY_USE | PNG_FLAG_CRC_ANCILLARY_NOWARN))
-         need_crc = 0;
-   }
-
-   else /* critical */
-   {
-      if (png_ptr->flags & PNG_FLAG_CRC_CRITICAL_IGNORE)
-         need_crc = 0;
-   }
-
-#ifdef PNG_IO_STATE_SUPPORTED
-   png_ptr->io_state = PNG_IO_READING | PNG_IO_CHUNK_CRC;
-#endif
-
-   /* The chunk CRC must be serialized in a single I/O call. */
-   png_read_data(png_ptr, crc_bytes, 4);
-
-   if (need_crc)
-   {
-      crc = png_get_uint_32(crc_bytes);
-      return ((int)(crc != png_ptr->crc));
-   }
-
-   else
-      return (0);
-}
-
-#ifdef PNG_READ_COMPRESSED_TEXT_SUPPORTED
-static png_size_t
-png_inflate(png_structp png_ptr, png_bytep data, png_size_t size,
-    png_bytep output, png_size_t output_size)
-{
-   png_size_t count = 0;
-
-   /* zlib can't necessarily handle more than 65535 bytes at once (i.e. it can't
-    * even necessarily handle 65536 bytes) because the type uInt is "16 bits or
-    * more".  Consequently it is necessary to chunk the input to zlib.  This
-    * code uses ZLIB_IO_MAX, from pngpriv.h, as the maximum (the maximum value
-    * that can be stored in a uInt.)  It is possible to set ZLIB_IO_MAX to a
-    * lower value in pngpriv.h and this may sometimes have a performance
-    * advantage, because it forces access of the input data to be separated from
-    * at least some of the use by some period of time.
-    */
-   png_ptr->zstream.next_in = data;
-   /* avail_in is set below from 'size' */
-   png_ptr->zstream.avail_in = 0;
-
-   while (1)
-   {
-      int ret, avail;
-
-      /* The setting of 'avail_in' used to be outside the loop; by setting it
-       * inside it is possible to chunk the input to zlib and simply rely on
-       * zlib to advance the 'next_in' pointer.  This allows arbitrary amounts o
-       * data to be passed through zlib at the unavoidable cost of requiring a
-       * window save (memcpy of up to 32768 output bytes) every ZLIB_IO_MAX
-       * input bytes.
-       */
-      if (png_ptr->zstream.avail_in == 0 && size > 0)
-      {
-         if (size <= ZLIB_IO_MAX)
-         {
-            /* The value is less than ZLIB_IO_MAX so the cast is safe: */
-            png_ptr->zstream.avail_in = (uInt)size;
-            size = 0;
-         }
-
-         else
-         {
-            png_ptr->zstream.avail_in = ZLIB_IO_MAX;
-            size -= ZLIB_IO_MAX;
-         }
-      }
-
-      /* Reset the output buffer each time round - we empty it
-       * after every inflate call.
-       */
-      png_ptr->zstream.next_out = png_ptr->zbuf;
-      png_ptr->zstream.avail_out = png_ptr->zbuf_size;
-
-      ret = inflate(&png_ptr->zstream, Z_NO_FLUSH);
-      avail = png_ptr->zbuf_size - png_ptr->zstream.avail_out;
-
-      /* First copy/count any new output - but only if we didn't
-       * get an error code.
-       */
-      if ((ret == Z_OK || ret == Z_STREAM_END) && avail > 0)
-      {
-         png_size_t space = avail; /* > 0, see above */
-
-         if (output != 0 && output_size > count)
-         {
-            png_size_t copy = output_size - count;
-
-            if (space < copy)
-               copy = space;
-
-            png_memcpy(output + count, png_ptr->zbuf, copy);
-         }
-         count += space;
-      }
-
-      if (ret == Z_OK)
-         continue;
-
-      /* Termination conditions - always reset the zstream, it
-       * must be left in inflateInit state.
-       */
-      png_ptr->zstream.avail_in = 0;
-      inflateReset(&png_ptr->zstream);
-
-      if (ret == Z_STREAM_END)
-         return count; /* NOTE: may be zero. */
-
-      /* Now handle the error codes - the API always returns 0
-       * and the error message is dumped into the uncompressed
-       * buffer if available.
-       */
-#     ifdef PNG_WARNINGS_SUPPORTED
-      {
-         png_const_charp msg;
-
-         if (png_ptr->zstream.msg != 0)
-            msg = png_ptr->zstream.msg;
-
-         else switch (ret)
-         {
-            case Z_BUF_ERROR:
-               msg = "Buffer error in compressed datastream";
-               break;
-
-            case Z_DATA_ERROR:
-               msg = "Data error in compressed datastream";
-               break;
-
-            default:
-               msg = "Incomplete compressed datastream";
-               break;
-         }
-
-         png_chunk_warning(png_ptr, msg);
-      }
-#     endif
-
-      /* 0 means an error - notice that this code simply ignores
-       * zero length compressed chunks as a result.
-       */
-      return 0;
-   }
-}
-
-/*
- * Decompress trailing data in a chunk.  The assumption is that chunkdata
- * points at an allocated area holding the contents of a chunk with a
- * trailing compressed part.  What we get back is an allocated area
- * holding the original prefix part and an uncompressed version of the
- * trailing part (the malloc area passed in is freed).
- */
-void /* PRIVATE */
-png_decompress_chunk(png_structp png_ptr, int comp_type,
-    png_size_t chunklength,
-    png_size_t prefix_size, png_size_t *newlength)
-{
-   /* The caller should guarantee this */
-   if (prefix_size > chunklength)
-   {
-      /* The recovery is to delete the chunk. */
-      png_warning(png_ptr, "invalid chunklength");
-      prefix_size = 0; /* To delete everything */
-   }
-
-   else if (comp_type == PNG_COMPRESSION_TYPE_BASE)
-   {
-      png_size_t expanded_size = png_inflate(png_ptr,
-          (png_bytep)(png_ptr->chunkdata + prefix_size),
-          chunklength - prefix_size,
-          0,            /* output */
-          0);           /* output size */
-
-      /* Now check the limits on this chunk - if the limit fails the
-       * compressed data will be removed, the prefix will remain.
-       */
-      if (prefix_size >= (~(png_size_t)0) - 1 ||
-         expanded_size >= (~(png_size_t)0) - 1 - prefix_size
-#ifdef PNG_USER_LIMITS_SUPPORTED
-         || (png_ptr->user_chunk_malloc_max &&
-          (prefix_size + expanded_size >= png_ptr->user_chunk_malloc_max - 1))
-#else
-         || ((PNG_USER_CHUNK_MALLOC_MAX > 0) &&
-          prefix_size + expanded_size >= PNG_USER_CHUNK_MALLOC_MAX - 1)
-#endif
-         )
-         png_warning(png_ptr, "Exceeded size limit while expanding chunk");
-
-      /* If the size is zero either there was an error and a message
-       * has already been output (warning) or the size really is zero
-       * and we have nothing to do - the code will exit through the
-       * error case below.
-       */
-      else if (expanded_size > 0)
-      {
-         /* Success (maybe) - really uncompress the chunk. */
-         png_size_t new_size = 0;
-         png_charp text = (png_charp)png_malloc_warn(png_ptr,
-             prefix_size + expanded_size + 1);
-
-         if (text != NULL)
-         {
-            png_memcpy(text, png_ptr->chunkdata, prefix_size);
-            new_size = png_inflate(png_ptr,
-                (png_bytep)(png_ptr->chunkdata + prefix_size),
-                chunklength - prefix_size,
-                (png_bytep)(text + prefix_size), expanded_size);
-            text[prefix_size + expanded_size] = 0; /* just in case */
-
-            if (new_size == expanded_size)
-            {
-               png_free(png_ptr, png_ptr->chunkdata);
-               png_ptr->chunkdata = text;
-               *newlength = prefix_size + expanded_size;
-               return; /* The success return! */
-            }
-
-            png_warning(png_ptr, "png_inflate logic error");
-            png_free(png_ptr, text);
-         }
-
-         else
-            png_warning(png_ptr, "Not enough memory to decompress chunk");
-      }
-   }
-
-   else /* if (comp_type != PNG_COMPRESSION_TYPE_BASE) */
-   {
-      PNG_WARNING_PARAMETERS(p)
-      png_warning_parameter_signed(p, 1, PNG_NUMBER_FORMAT_d, comp_type);
-      png_formatted_warning(png_ptr, p, "Unknown compression type @1");
-
-      /* The recovery is to simply drop the data. */
-   }
-
-   /* Generic error return - leave the prefix, delete the compressed
-    * data, reallocate the chunkdata to remove the potentially large
-    * amount of compressed data.
-    */
-   {
-      png_charp text = (png_charp)png_malloc_warn(png_ptr, prefix_size + 1);
-
-      if (text != NULL)
-      {
-         if (prefix_size > 0)
-            png_memcpy(text, png_ptr->chunkdata, prefix_size);
-
-         png_free(png_ptr, png_ptr->chunkdata);
-         png_ptr->chunkdata = text;
-
-         /* This is an extra zero in the 'uncompressed' part. */
-         *(png_ptr->chunkdata + prefix_size) = 0x00;
-      }
-      /* Ignore a malloc error here - it is safe. */
-   }
-
-   *newlength = prefix_size;
-}
-#endif /* PNG_READ_COMPRESSED_TEXT_SUPPORTED */
-
-/* Read and check the IDHR chunk */
-void /* PRIVATE */
-png_handle_IHDR(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
-{
-   png_byte buf[13];
-   png_uint_32 width, height;
-   int bit_depth, color_type, compression_type, filter_type;
-   int interlace_type;
-
-   png_debug(1, "in png_handle_IHDR");
-
-   if (png_ptr->mode & PNG_HAVE_IHDR)
-      dg_png_error(png_ptr, "Out of place IHDR");
-
-   /* Check the length */
-   if (length != 13)
-      dg_png_error(png_ptr, "Invalid IHDR chunk");
-
-   png_ptr->mode |= PNG_HAVE_IHDR;
-
-   png_crc_read(png_ptr, buf, 13);
-   png_crc_finish(png_ptr, 0);
-
-   width = png_get_uint_31(png_ptr, buf);
-   height = png_get_uint_31(png_ptr, buf + 4);
-   bit_depth = buf[8];
-   color_type = buf[9];
-   compression_type = buf[10];
-   filter_type = buf[11];
-   interlace_type = buf[12];
-
-   /* Set internal variables */
-   png_ptr->width = width;
-   png_ptr->height = height;
-   png_ptr->bit_depth = (png_byte)bit_depth;
-   png_ptr->interlaced = (png_byte)interlace_type;
-   png_ptr->color_type = (png_byte)color_type;
-#ifdef PNG_MNG_FEATURES_SUPPORTED
-   png_ptr->filter_type = (png_byte)filter_type;
-#endif
-   png_ptr->compression_type = (png_byte)compression_type;
-
-   /* Find number of channels */
-   switch (png_ptr->color_type)
-   {
-      default: /* invalid, png_set_IHDR calls png_error */
-      case PNG_COLOR_TYPE_GRAY:
-      case PNG_COLOR_TYPE_PALETTE:
-         png_ptr->channels = 1;
-         break;
-
-      case PNG_COLOR_TYPE_RGB:
-         png_ptr->channels = 3;
-         break;
-
-      case PNG_COLOR_TYPE_GRAY_ALPHA:
-         png_ptr->channels = 2;
-         break;
-
-      case PNG_COLOR_TYPE_RGB_ALPHA:
-         png_ptr->channels = 4;
-         break;
-   }
-
-   /* Set up other useful info */
-   png_ptr->pixel_depth = (png_byte)(png_ptr->bit_depth *
-   png_ptr->channels);
-   png_ptr->rowbytes = PNG_ROWBYTES(png_ptr->pixel_depth, png_ptr->width);
-   png_debug1(3, "bit_depth = %d", png_ptr->bit_depth);
-   png_debug1(3, "channels = %d", png_ptr->channels);
-   png_debug1(3, "rowbytes = %lu", (unsigned long)png_ptr->rowbytes);
-   png_set_IHDR(png_ptr, info_ptr, width, height, bit_depth,
-       color_type, interlace_type, compression_type, filter_type);
-}
-
-/* Read and check the palette */
-void /* PRIVATE */
-png_handle_PLTE(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
-{
-   png_color palette[PNG_MAX_PALETTE_LENGTH];
-   int num, i;
-#ifdef PNG_POINTER_INDEXING_SUPPORTED
-   png_colorp pal_ptr;
-#endif
-
-   png_debug(1, "in png_handle_PLTE");
-
-   if (!(png_ptr->mode & PNG_HAVE_IHDR))
-      dg_png_error(png_ptr, "Missing IHDR before PLTE");
-
-   else if (png_ptr->mode & PNG_HAVE_IDAT)
-   {
-      png_warning(png_ptr, "Invalid PLTE after IDAT");
-      png_crc_finish(png_ptr, length);
-      return;
-   }
-
-   else if (png_ptr->mode & PNG_HAVE_PLTE)
-      dg_png_error(png_ptr, "Duplicate PLTE chunk");
-
-   png_ptr->mode |= PNG_HAVE_PLTE;
-
-   if (!(png_ptr->color_type&PNG_COLOR_MASK_COLOR))
-   {
-      png_warning(png_ptr,
-          "Ignoring PLTE chunk in grayscale PNG");
-      png_crc_finish(png_ptr, length);
-      return;
-   }
-
-#ifndef PNG_READ_OPT_PLTE_SUPPORTED
-   if (png_ptr->color_type != PNG_COLOR_TYPE_PALETTE)
-   {
-      png_crc_finish(png_ptr, length);
-      return;
-   }
-#endif
-
-   if (length > 3*PNG_MAX_PALETTE_LENGTH || length % 3)
-   {
-      if (png_ptr->color_type != PNG_COLOR_TYPE_PALETTE)
-      {
-         png_warning(png_ptr, "Invalid palette chunk");
-         png_crc_finish(png_ptr, length);
-         return;
-      }
-
-      else
-      {
-         dg_png_error(png_ptr, "Invalid palette chunk");
-      }
-   }
-
-   num = (int)length / 3;
-
-#ifdef PNG_POINTER_INDEXING_SUPPORTED
-   for (i = 0, pal_ptr = palette; i < num; i++, pal_ptr++)
-   {
-      png_byte buf[3];
-
-      png_crc_read(png_ptr, buf, 3);
-      pal_ptr->red = buf[0];
-      pal_ptr->green = buf[1];
-      pal_ptr->blue = buf[2];
-   }
-#else
-   for (i = 0; i < num; i++)
-   {
-      png_byte buf[3];
-
-      png_crc_read(png_ptr, buf, 3);
-      /* Don't depend upon png_color being any order */
-      palette[i].red = buf[0];
-      palette[i].green = buf[1];
-      palette[i].blue = buf[2];
-   }
-#endif
-
-   /* If we actually need the PLTE chunk (ie for a paletted image), we do
-    * whatever the normal CRC configuration tells us.  However, if we
-    * have an RGB image, the PLTE can be considered ancillary, so
-    * we will act as though it is.
-    */
-#ifndef PNG_READ_OPT_PLTE_SUPPORTED
-   if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE)
-#endif
-   {
-      png_crc_finish(png_ptr, 0);
-   }
-
-#ifndef PNG_READ_OPT_PLTE_SUPPORTED
-   else if (png_crc_error(png_ptr))  /* Only if we have a CRC error */
-   {
-      /* If we don't want to use the data from an ancillary chunk,
-       * we have two options: an error abort, or a warning and we
-       * ignore the data in this chunk (which should be OK, since
-       * it's considered ancillary for a RGB or RGBA image).
-       */
-      if (!(png_ptr->flags & PNG_FLAG_CRC_ANCILLARY_USE))
-      {
-         if (png_ptr->flags & PNG_FLAG_CRC_ANCILLARY_NOWARN)
-         {
-            png_chunk_benign_error(png_ptr, "CRC error");
-         }
-
-         else
-         {
-            png_chunk_warning(png_ptr, "CRC error");
-            return;
-         }
-      }
-
-      /* Otherwise, we (optionally) emit a warning and use the chunk. */
-      else if (!(png_ptr->flags & PNG_FLAG_CRC_ANCILLARY_NOWARN))
-      {
-         png_chunk_warning(png_ptr, "CRC error");
-      }
-   }
-#endif
-
-   png_set_PLTE(png_ptr, info_ptr, palette, num);
-
-#ifdef PNG_READ_tRNS_SUPPORTED
-   if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE)
-   {
-      if (info_ptr != NULL && (info_ptr->valid & PNG_INFO_tRNS))
-      {
-         if (png_ptr->num_trans > (png_uint_16)num)
-         {
-            png_warning(png_ptr, "Truncating incorrect tRNS chunk length");
-            png_ptr->num_trans = (png_uint_16)num;
-         }
-
-         if (info_ptr->num_trans > (png_uint_16)num)
-         {
-            png_warning(png_ptr, "Truncating incorrect info tRNS chunk length");
-            info_ptr->num_trans = (png_uint_16)num;
-         }
-      }
-   }
-#endif
-
-}
-
-void /* PRIVATE */
-png_handle_IEND(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
-{
-   png_debug(1, "in png_handle_IEND");
-
-   if (!(png_ptr->mode & PNG_HAVE_IHDR) || !(png_ptr->mode & PNG_HAVE_IDAT))
-   {
-      dg_png_error(png_ptr, "No image in file");
-   }
-
-   png_ptr->mode |= (PNG_AFTER_IDAT | PNG_HAVE_IEND);
-
-   if (length != 0)
-   {
-      png_warning(png_ptr, "Incorrect IEND chunk length");
-   }
-
-   png_crc_finish(png_ptr, length);
-
-   PNG_UNUSED(info_ptr) /* Quiet compiler warnings about unused info_ptr */
-}
-
-#ifdef PNG_READ_gAMA_SUPPORTED
-void /* PRIVATE */
-png_handle_gAMA(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
-{
-   png_fixed_point igamma;
-   png_byte buf[4];
-
-   png_debug(1, "in png_handle_gAMA");
-
-   if (!(png_ptr->mode & PNG_HAVE_IHDR))
-      dg_png_error(png_ptr, "Missing IHDR before gAMA");
-
-   else if (png_ptr->mode & PNG_HAVE_IDAT)
-   {
-      png_warning(png_ptr, "Invalid gAMA after IDAT");
-      png_crc_finish(png_ptr, length);
-      return;
-   }
-
-   else if (png_ptr->mode & PNG_HAVE_PLTE)
-      /* Should be an error, but we can cope with it */
-      png_warning(png_ptr, "Out of place gAMA chunk");
-
-   if (info_ptr != NULL && (info_ptr->valid & PNG_INFO_gAMA)
-#ifdef PNG_READ_sRGB_SUPPORTED
-       && !(info_ptr->valid & PNG_INFO_sRGB)
-#endif
-       )
-   {
-      png_warning(png_ptr, "Duplicate gAMA chunk");
-      png_crc_finish(png_ptr, length);
-      return;
-   }
-
-   if (length != 4)
-   {
-      png_warning(png_ptr, "Incorrect gAMA chunk length");
-      png_crc_finish(png_ptr, length);
-      return;
-   }
-
-   png_crc_read(png_ptr, buf, 4);
-
-   if (png_crc_finish(png_ptr, 0))
-      return;
-
-   igamma = png_get_fixed_point(NULL, buf);
-
-   /* Check for zero gamma or an error. */
-   if (igamma <= 0)
-   {
-      png_warning(png_ptr,
-          "Ignoring gAMA chunk with out of range gamma");
-
-      return;
-   }
-
-#  ifdef PNG_READ_sRGB_SUPPORTED
-   if (info_ptr != NULL && (info_ptr->valid & PNG_INFO_sRGB))
-   {
-      if (PNG_OUT_OF_RANGE(igamma, 45500, 500))
-      {
-         PNG_WARNING_PARAMETERS(p)
-         png_warning_parameter_signed(p, 1, PNG_NUMBER_FORMAT_fixed, igamma);
-         png_formatted_warning(png_ptr, p,
-             "Ignoring incorrect gAMA value @1 when sRGB is also present");
-         return;
-      }
-   }
-#  endif /* PNG_READ_sRGB_SUPPORTED */
-
-#  ifdef PNG_READ_GAMMA_SUPPORTED
-   /* Gamma correction on read is supported. */
-   png_ptr->gamma = igamma;
-#  endif
-   /* And set the 'info' structure members. */
-   png_set_gAMA_fixed(png_ptr, info_ptr, igamma);
-}
-#endif
-
-#ifdef PNG_READ_sBIT_SUPPORTED
-void /* PRIVATE */
-png_handle_sBIT(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
-{
-   png_size_t truelen;
-   png_byte buf[4];
-
-   png_debug(1, "in png_handle_sBIT");
-
-   buf[0] = buf[1] = buf[2] = buf[3] = 0;
-
-   if (!(png_ptr->mode & PNG_HAVE_IHDR))
-      dg_png_error(png_ptr, "Missing IHDR before sBIT");
-
-   else if (png_ptr->mode & PNG_HAVE_IDAT)
-   {
-      png_warning(png_ptr, "Invalid sBIT after IDAT");
-      png_crc_finish(png_ptr, length);
-      return;
-   }
-
-   else if (png_ptr->mode & PNG_HAVE_PLTE)
-   {
-      /* Should be an error, but we can cope with it */
-      png_warning(png_ptr, "Out of place sBIT chunk");
-   }
-
-   if (info_ptr != NULL && (info_ptr->valid & PNG_INFO_sBIT))
-   {
-      png_warning(png_ptr, "Duplicate sBIT chunk");
-      png_crc_finish(png_ptr, length);
-      return;
-   }
-
-   if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE)
-      truelen = 3;
-
-   else
-      truelen = (png_size_t)png_ptr->channels;
-
-   if (length != truelen || length > 4)
-   {
-      png_warning(png_ptr, "Incorrect sBIT chunk length");
-      png_crc_finish(png_ptr, length);
-      return;
-   }
-
-   png_crc_read(png_ptr, buf, truelen);
-
-   if (png_crc_finish(png_ptr, 0))
-      return;
-
-   if (png_ptr->color_type & PNG_COLOR_MASK_COLOR)
-   {
-      png_ptr->sig_bit.red = buf[0];
-      png_ptr->sig_bit.green = buf[1];
-      png_ptr->sig_bit.blue = buf[2];
-      png_ptr->sig_bit.alpha = buf[3];
-   }
-
-   else
-   {
-      png_ptr->sig_bit.gray = buf[0];
-      png_ptr->sig_bit.red = buf[0];
-      png_ptr->sig_bit.green = buf[0];
-      png_ptr->sig_bit.blue = buf[0];
-      png_ptr->sig_bit.alpha = buf[1];
-   }
-
-   png_set_sBIT(png_ptr, info_ptr, &(png_ptr->sig_bit));
-}
-#endif
-
-#ifdef PNG_READ_cHRM_SUPPORTED
-void /* PRIVATE */
-png_handle_cHRM(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
-{
-   png_byte buf[32];
-   png_fixed_point x_white, y_white, x_red, y_red, x_green, y_green, x_blue,
-      y_blue;
-
-   png_debug(1, "in png_handle_cHRM");
-
-   if (!(png_ptr->mode & PNG_HAVE_IHDR))
-      dg_png_error(png_ptr, "Missing IHDR before cHRM");
-
-   else if (png_ptr->mode & PNG_HAVE_IDAT)
-   {
-      png_warning(png_ptr, "Invalid cHRM after IDAT");
-      png_crc_finish(png_ptr, length);
-      return;
-   }
-
-   else if (png_ptr->mode & PNG_HAVE_PLTE)
-      /* Should be an error, but we can cope with it */
-      png_warning(png_ptr, "Out of place cHRM chunk");
-
-   if (info_ptr != NULL && (info_ptr->valid & PNG_INFO_cHRM)
-#  ifdef PNG_READ_sRGB_SUPPORTED
-       && !(info_ptr->valid & PNG_INFO_sRGB)
-#  endif
-      )
-   {
-      png_warning(png_ptr, "Duplicate cHRM chunk");
-      png_crc_finish(png_ptr, length);
-      return;
-   }
-
-   if (length != 32)
-   {
-      png_warning(png_ptr, "Incorrect cHRM chunk length");
-      png_crc_finish(png_ptr, length);
-      return;
-   }
-
-   png_crc_read(png_ptr, buf, 32);
-
-   if (png_crc_finish(png_ptr, 0))
-      return;
-
-   x_white = png_get_fixed_point(NULL, buf);
-   y_white = png_get_fixed_point(NULL, buf + 4);
-   x_red   = png_get_fixed_point(NULL, buf + 8);
-   y_red   = png_get_fixed_point(NULL, buf + 12);
-   x_green = png_get_fixed_point(NULL, buf + 16);
-   y_green = png_get_fixed_point(NULL, buf + 20);
-   x_blue  = png_get_fixed_point(NULL, buf + 24);
-   y_blue  = png_get_fixed_point(NULL, buf + 28);
-
-   if (x_white == PNG_FIXED_ERROR ||
-       y_white == PNG_FIXED_ERROR ||
-       x_red   == PNG_FIXED_ERROR ||
-       y_red   == PNG_FIXED_ERROR ||
-       x_green == PNG_FIXED_ERROR ||
-       y_green == PNG_FIXED_ERROR ||
-       x_blue  == PNG_FIXED_ERROR ||
-       y_blue  == PNG_FIXED_ERROR)
-   {
-      png_warning(png_ptr, "Ignoring cHRM chunk with negative chromaticities");
-      return;
-   }
-
-#ifdef PNG_READ_sRGB_SUPPORTED
-   if ((info_ptr != NULL) && (info_ptr->valid & PNG_INFO_sRGB))
-   {
-      if (PNG_OUT_OF_RANGE(x_white, 31270,  1000) ||
-          PNG_OUT_OF_RANGE(y_white, 32900,  1000) ||
-          PNG_OUT_OF_RANGE(x_red,   64000,  1000) ||
-          PNG_OUT_OF_RANGE(y_red,   33000,  1000) ||
-          PNG_OUT_OF_RANGE(x_green, 30000,  1000) ||
-          PNG_OUT_OF_RANGE(y_green, 60000,  1000) ||
-          PNG_OUT_OF_RANGE(x_blue,  15000,  1000) ||
-          PNG_OUT_OF_RANGE(y_blue,   6000,  1000))
-      {
-         PNG_WARNING_PARAMETERS(p)
-
-         png_warning_parameter_signed(p, 1, PNG_NUMBER_FORMAT_fixed, x_white);
-         png_warning_parameter_signed(p, 2, PNG_NUMBER_FORMAT_fixed, y_white);
-         png_warning_parameter_signed(p, 3, PNG_NUMBER_FORMAT_fixed, x_red);
-         png_warning_parameter_signed(p, 4, PNG_NUMBER_FORMAT_fixed, y_red);
-         png_warning_parameter_signed(p, 5, PNG_NUMBER_FORMAT_fixed, x_green);
-         png_warning_parameter_signed(p, 6, PNG_NUMBER_FORMAT_fixed, y_green);
-         png_warning_parameter_signed(p, 7, PNG_NUMBER_FORMAT_fixed, x_blue);
-         png_warning_parameter_signed(p, 8, PNG_NUMBER_FORMAT_fixed, y_blue);
-
-         png_formatted_warning(png_ptr, p,
-             "Ignoring incorrect cHRM white(@1,@2) r(@3,@4)g(@5,@6)b(@7,@8) "
-             "when sRGB is also present");
-      }
-      return;
-   }
-#endif /* PNG_READ_sRGB_SUPPORTED */
-
-#ifdef PNG_READ_RGB_TO_GRAY_SUPPORTED
-   /* Store the _white values as default coefficients for the rgb to gray
-    * operation if it is supported.  Check if the transform is already set to
-    * avoid destroying the transform values.
-    */
-   if (!png_ptr->rgb_to_gray_coefficients_set)
-   {
-      /* png_set_background has not been called and we haven't seen an sRGB
-       * chunk yet.  Find the XYZ of the three end points.
-       */
-      png_XYZ XYZ;
-      png_xy xy;
-
-      xy.redx = x_red;
-      xy.redy = y_red;
-      xy.greenx = x_green;
-      xy.greeny = y_green;
-      xy.bluex = x_blue;
-      xy.bluey = y_blue;
-      xy.whitex = x_white;
-      xy.whitey = y_white;
-
-      if (png_XYZ_from_xy_checked(png_ptr, &XYZ, xy))
-      {
-         /* The success case, because XYZ_from_xy normalises to a reference
-          * white Y of 1.0 we just need to scale the numbers.  This should
-          * always work just fine. It is an internal error if this overflows.
-          */
-         {
-            png_fixed_point r, g, b;
-            if (png_muldiv(&r, XYZ.redY, 32768, PNG_FP_1) &&
-               r >= 0 && r <= 32768 &&
-               png_muldiv(&g, XYZ.greenY, 32768, PNG_FP_1) &&
-               g >= 0 && g <= 32768 &&
-               png_muldiv(&b, XYZ.blueY, 32768, PNG_FP_1) &&
-               b >= 0 && b <= 32768 &&
-               r+g+b <= 32769)
-            {
-               /* We allow 0 coefficients here.  r+g+b may be 32769 if two or
-                * all of the coefficients were rounded up.  Handle this by
-                * reducing the *largest* coefficient by 1; this matches the
-                * approach used for the default coefficients in pngrtran.c
-                */
-               int add = 0;
-
-               if (r+g+b > 32768)
-                  add = -1;
-               else if (r+g+b < 32768)
-                  add = 1;
-
-               if (add != 0)
-               {
-                  if (g >= r && g >= b)
-                     g += add;
-                  else if (r >= g && r >= b)
-                     r += add;
-                  else
-                     b += add;
-               }
-
-               /* Check for an internal error. */
-               if (r+g+b != 32768)
-                  dg_png_error(png_ptr,
-                     "internal error handling cHRM coefficients");
-
-               png_ptr->rgb_to_gray_red_coeff   = (png_uint_16)r;
-               png_ptr->rgb_to_gray_green_coeff = (png_uint_16)g;
-            }
-
-            /* This is a png_error at present even though it could be ignored -
-             * it should never happen, but it is important that if it does, the
-             * bug is fixed.
-             */
-            else
-               dg_png_error(png_ptr, "internal error handling cHRM->XYZ");
-         }
-      }
-   }
-#endif
-
-   png_set_cHRM_fixed(png_ptr, info_ptr, x_white, y_white, x_red, y_red,
-      x_green, y_green, x_blue, y_blue);
-}
-#endif
-
-#ifdef PNG_READ_sRGB_SUPPORTED
-void /* PRIVATE */
-png_handle_sRGB(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
-{
-   int intent;
-   png_byte buf[1];
-
-   png_debug(1, "in png_handle_sRGB");
-
-   if (!(png_ptr->mode & PNG_HAVE_IHDR))
-      dg_png_error(png_ptr, "Missing IHDR before sRGB");
-
-   else if (png_ptr->mode & PNG_HAVE_IDAT)
-   {
-      png_warning(png_ptr, "Invalid sRGB after IDAT");
-      png_crc_finish(png_ptr, length);
-      return;
-   }
-
-   else if (png_ptr->mode & PNG_HAVE_PLTE)
-      /* Should be an error, but we can cope with it */
-      png_warning(png_ptr, "Out of place sRGB chunk");
-
-   if (info_ptr != NULL && (info_ptr->valid & PNG_INFO_sRGB))
-   {
-      png_warning(png_ptr, "Duplicate sRGB chunk");
-      png_crc_finish(png_ptr, length);
-      return;
-   }
-
-   if (length != 1)
-   {
-      png_warning(png_ptr, "Incorrect sRGB chunk length");
-      png_crc_finish(png_ptr, length);
-      return;
-   }
-
-   png_crc_read(png_ptr, buf, 1);
-
-   if (png_crc_finish(png_ptr, 0))
-      return;
-
-   intent = buf[0];
-
-   /* Check for bad intent */
-   if (intent >= PNG_sRGB_INTENT_LAST)
-   {
-      png_warning(png_ptr, "Unknown sRGB intent");
-      return;
-   }
-
-#if defined(PNG_READ_gAMA_SUPPORTED) && defined(PNG_READ_GAMMA_SUPPORTED)
-   if (info_ptr != NULL && (info_ptr->valid & PNG_INFO_gAMA))
-   {
-      if (PNG_OUT_OF_RANGE(info_ptr->gamma, 45500, 500))
-      {
-         PNG_WARNING_PARAMETERS(p)
-
-         png_warning_parameter_signed(p, 1, PNG_NUMBER_FORMAT_fixed,
-            info_ptr->gamma);
-
-         png_formatted_warning(png_ptr, p,
-             "Ignoring incorrect gAMA value @1 when sRGB is also present");
-      }
-   }
-#endif /* PNG_READ_gAMA_SUPPORTED */
-
-#ifdef PNG_READ_cHRM_SUPPORTED
-   if (info_ptr != NULL && (info_ptr->valid & PNG_INFO_cHRM))
-      if (PNG_OUT_OF_RANGE(info_ptr->x_white, 31270,  1000) ||
-          PNG_OUT_OF_RANGE(info_ptr->y_white, 32900,  1000) ||
-          PNG_OUT_OF_RANGE(info_ptr->x_red,   64000,  1000) ||
-          PNG_OUT_OF_RANGE(info_ptr->y_red,   33000,  1000) ||
-          PNG_OUT_OF_RANGE(info_ptr->x_green, 30000,  1000) ||
-          PNG_OUT_OF_RANGE(info_ptr->y_green, 60000,  1000) ||
-          PNG_OUT_OF_RANGE(info_ptr->x_blue,  15000,  1000) ||
-          PNG_OUT_OF_RANGE(info_ptr->y_blue,   6000,  1000))
-      {
-         png_warning(png_ptr,
-             "Ignoring incorrect cHRM value when sRGB is also present");
-      }
-#endif /* PNG_READ_cHRM_SUPPORTED */
-
-   /* This is recorded for use when handling the cHRM chunk above.  An sRGB
-    * chunk unconditionally overwrites the coefficients for grayscale conversion
-    * too.
-    */
-   png_ptr->is_sRGB = 1;
-
-#  ifdef PNG_READ_RGB_TO_GRAY_SUPPORTED
-      /* Don't overwrite user supplied values: */
-      if (!png_ptr->rgb_to_gray_coefficients_set)
-      {
-         /* These numbers come from the sRGB specification (or, since one has to
-          * pay much money to get a copy, the wikipedia sRGB page) the
-          * chromaticity values quoted have been inverted to get the reverse
-          * transformation from RGB to XYZ and the 'Y' coefficients scaled by
-          * 32768 (then rounded).
-          *
-          * sRGB and ITU Rec-709 both truncate the values for the D65 white
-          * point to four digits and, even though it actually stores five
-          * digits, the PNG spec gives the truncated value.
-          *
-          * This means that when the chromaticities are converted back to XYZ
-          * end points we end up with (6968,23435,2366), which, as described in
-          * pngrtran.c, would overflow.  If the five digit precision and up is
-          * used we get, instead:
-          *
-          *    6968*R + 23435*G + 2365*B
-          *
-          * (Notice that this rounds the blue coefficient down, rather than the
-          * choice used in pngrtran.c which is to round the green one down.)
-          */
-         png_ptr->rgb_to_gray_red_coeff   =  6968; /* 0.212639005871510 */
-         png_ptr->rgb_to_gray_green_coeff = 23434; /* 0.715168678767756 */
-         /* png_ptr->rgb_to_gray_blue_coeff  =  2366; 0.072192315360734	*/
-
-         /* The following keeps the cHRM chunk from destroying the
-          * coefficients again in the event that it follows the sRGB chunk.
-          */
-         png_ptr->rgb_to_gray_coefficients_set = 1;
-      }
-#  endif
-
-   png_set_sRGB_gAMA_and_cHRM(png_ptr, info_ptr, intent);
-}
-#endif /* PNG_READ_sRGB_SUPPORTED */
-
-#ifdef PNG_READ_iCCP_SUPPORTED
-void /* PRIVATE */
-png_handle_iCCP(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
-/* Note: this does not properly handle chunks that are > 64K under DOS */
-{
-   png_byte compression_type;
-   png_bytep pC;
-   png_charp profile;
-   png_uint_32 skip = 0;
-   png_uint_32 profile_size;
-   png_alloc_size_t profile_length;
-   png_size_t slength, prefix_length, data_length;
-
-   png_debug(1, "in png_handle_iCCP");
-
-   if (!(png_ptr->mode & PNG_HAVE_IHDR))
-      dg_png_error(png_ptr, "Missing IHDR before iCCP");
-
-   else if (png_ptr->mode & PNG_HAVE_IDAT)
-   {
-      png_warning(png_ptr, "Invalid iCCP after IDAT");
-      png_crc_finish(png_ptr, length);
-      return;
-   }
-
-   else if (png_ptr->mode & PNG_HAVE_PLTE)
-      /* Should be an error, but we can cope with it */
-      png_warning(png_ptr, "Out of place iCCP chunk");
-
-   if ((png_ptr->mode & PNG_HAVE_iCCP) || (info_ptr != NULL &&
-      (info_ptr->valid & (PNG_INFO_iCCP|PNG_INFO_sRGB))))
-   {
-      png_warning(png_ptr, "Duplicate iCCP chunk");
-      png_crc_finish(png_ptr, length);
-      return;
-   }
-
-   png_ptr->mode |= PNG_HAVE_iCCP;
-
-#ifdef PNG_MAX_MALLOC_64K
-   if (length > (png_uint_32)65535L)
-   {
-      png_warning(png_ptr, "iCCP chunk too large to fit in memory");
-      skip = length - (png_uint_32)65535L;
-      length = (png_uint_32)65535L;
-   }
-#endif
-
-   png_free(png_ptr, png_ptr->chunkdata);
-   png_ptr->chunkdata = (png_charp)png_malloc(png_ptr, length + 1);
-   slength = length;
-   png_crc_read(png_ptr, (png_bytep)png_ptr->chunkdata, slength);
-
-   if (png_crc_finish(png_ptr, skip))
-   {
-      png_free(png_ptr, png_ptr->chunkdata);
-      png_ptr->chunkdata = NULL;
-      return;
-   }
-
-   png_ptr->chunkdata[slength] = 0x00;
-
-   for (profile = png_ptr->chunkdata; *profile; profile++)
-      /* Empty loop to find end of name */ ;
-
-   ++profile;
-
-   /* There should be at least one zero (the compression type byte)
-    * following the separator, and we should be on it
-    */
-   if (profile >= png_ptr->chunkdata + slength - 1)
-   {
-      png_free(png_ptr, png_ptr->chunkdata);
-      png_ptr->chunkdata = NULL;
-      png_warning(png_ptr, "Malformed iCCP chunk");
-      return;
-   }
-
-   /* Compression_type should always be zero */
-   compression_type = *profile++;
-
-   if (compression_type)
-   {
-      png_warning(png_ptr, "Ignoring nonzero compression type in iCCP chunk");
-      compression_type = 0x00;  /* Reset it to zero (libpng-1.0.6 through 1.0.8
-                                 wrote nonzero) */
-   }
-
-   prefix_length = profile - png_ptr->chunkdata;
-   png_decompress_chunk(png_ptr, compression_type,
-       slength, prefix_length, &data_length);
-
-   profile_length = data_length - prefix_length;
-
-   if (prefix_length > data_length || profile_length < 4)
-   {
-      png_free(png_ptr, png_ptr->chunkdata);
-      png_ptr->chunkdata = NULL;
-      png_warning(png_ptr, "Profile size field missing from iCCP chunk");
-      return;
-   }
-
-   /* Check the profile_size recorded in the first 32 bits of the ICC profile */
-   pC = (png_bytep)(png_ptr->chunkdata + prefix_length);
-   profile_size = ((*(pC    )) << 24) |
-                  ((*(pC + 1)) << 16) |
-                  ((*(pC + 2)) <<  8) |
-                  ((*(pC + 3))      );
-
-   /* NOTE: the following guarantees that 'profile_length' fits into 32 bits,
-    * because profile_size is a 32 bit value.
-    */
-   if (profile_size < profile_length)
-      profile_length = profile_size;
-
-   /* And the following guarantees that profile_size == profile_length. */
-   if (profile_size > profile_length)
-   {
-      PNG_WARNING_PARAMETERS(p)
-
-      png_free(png_ptr, png_ptr->chunkdata);
-      png_ptr->chunkdata = NULL;
-
-      png_warning_parameter_unsigned(p, 1, PNG_NUMBER_FORMAT_u, profile_size);
-      png_warning_parameter_unsigned(p, 2, PNG_NUMBER_FORMAT_u, profile_length);
-      png_formatted_warning(png_ptr, p,
-         "Ignoring iCCP chunk with declared size = @1 and actual length = @2");
-      return;
-   }
-
-   png_set_iCCP(png_ptr, info_ptr, png_ptr->chunkdata,
-       compression_type, (png_bytep)png_ptr->chunkdata + prefix_length,
-       profile_size);
-   png_free(png_ptr, png_ptr->chunkdata);
-   png_ptr->chunkdata = NULL;
-}
-#endif /* PNG_READ_iCCP_SUPPORTED */
-
-#ifdef PNG_READ_sPLT_SUPPORTED
-void /* PRIVATE */
-png_handle_sPLT(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
-/* Note: this does not properly handle chunks that are > 64K under DOS */
-{
-   png_bytep entry_start;
-   png_sPLT_t new_palette;
-   png_sPLT_entryp pp;
-   png_uint_32 data_length;
-   int entry_size, i;
-   png_uint_32 skip = 0;
-   png_size_t slength;
-   png_uint_32 dl;
-   png_size_t max_dl;
-
-   png_debug(1, "in png_handle_sPLT");
-
-#ifdef PNG_USER_LIMITS_SUPPORTED
-
-   if (png_ptr->user_chunk_cache_max != 0)
-   {
-      if (png_ptr->user_chunk_cache_max == 1)
-      {
-         png_crc_finish(png_ptr, length);
-         return;
-      }
-
-      if (--png_ptr->user_chunk_cache_max == 1)
-      {
-         png_warning(png_ptr, "No space in chunk cache for sPLT");
-         png_crc_finish(png_ptr, length);
-         return;
-      }
-   }
-#endif
-
-   if (!(png_ptr->mode & PNG_HAVE_IHDR))
-      dg_png_error(png_ptr, "Missing IHDR before sPLT");
-
-   else if (png_ptr->mode & PNG_HAVE_IDAT)
-   {
-      png_warning(png_ptr, "Invalid sPLT after IDAT");
-      png_crc_finish(png_ptr, length);
-      return;
-   }
-
-#ifdef PNG_MAX_MALLOC_64K
-   if (length > (png_uint_32)65535L)
-   {
-      png_warning(png_ptr, "sPLT chunk too large to fit in memory");
-      skip = length - (png_uint_32)65535L;
-      length = (png_uint_32)65535L;
-   }
-#endif
-
-   png_free(png_ptr, png_ptr->chunkdata);
-   png_ptr->chunkdata = (png_charp)png_malloc(png_ptr, length + 1);
-
-   /* WARNING: this may break if size_t is less than 32 bits; it is assumed
-    * that the PNG_MAX_MALLOC_64K test is enabled in this case, but this is a
-    * potential breakage point if the types in pngconf.h aren't exactly right.
-    */
-   slength = length;
-   png_crc_read(png_ptr, (png_bytep)png_ptr->chunkdata, slength);
-
-   if (png_crc_finish(png_ptr, skip))
-   {
-      png_free(png_ptr, png_ptr->chunkdata);
-      png_ptr->chunkdata = NULL;
-      return;
-   }
-
-   png_ptr->chunkdata[slength] = 0x00;
-
-   for (entry_start = (png_bytep)png_ptr->chunkdata; *entry_start;
-       entry_start++)
-      /* Empty loop to find end of name */ ;
-
-   ++entry_start;
-
-   /* A sample depth should follow the separator, and we should be on it  */
-   if (entry_start > (png_bytep)png_ptr->chunkdata + slength - 2)
-   {
-      png_free(png_ptr, png_ptr->chunkdata);
-      png_ptr->chunkdata = NULL;
-      png_warning(png_ptr, "malformed sPLT chunk");
-      return;
-   }
-
-   new_palette.depth = *entry_start++;
-   entry_size = (new_palette.depth == 8 ? 6 : 10);
-   /* This must fit in a png_uint_32 because it is derived from the original
-    * chunk data length (and use 'length', not 'slength' here for clarity -
-    * they are guaranteed to be the same, see the tests above.)
-    */
-   data_length = length - (png_uint_32)(entry_start -
-      (png_bytep)png_ptr->chunkdata);
-
-   /* Integrity-check the data length */
-   if (data_length % entry_size)
-   {
-      png_free(png_ptr, png_ptr->chunkdata);
-      png_ptr->chunkdata = NULL;
-      png_warning(png_ptr, "sPLT chunk has bad length");
-      return;
-   }
-
-   dl = (png_int_32)(data_length / entry_size);
-   max_dl = PNG_SIZE_MAX / png_sizeof(png_sPLT_entry);
-
-   if (dl > max_dl)
-   {
-       png_warning(png_ptr, "sPLT chunk too long");
-       return;
-   }
-
-   new_palette.nentries = (png_int_32)(data_length / entry_size);
-
-   new_palette.entries = (png_sPLT_entryp)png_malloc_warn(
-       png_ptr, new_palette.nentries * png_sizeof(png_sPLT_entry));
-
-   if (new_palette.entries == NULL)
-   {
-       png_warning(png_ptr, "sPLT chunk requires too much memory");
-       return;
-   }
-
-#ifdef PNG_POINTER_INDEXING_SUPPORTED
-   for (i = 0; i < new_palette.nentries; i++)
-   {
-      pp = new_palette.entries + i;
-
-      if (new_palette.depth == 8)
-      {
-         pp->red = *entry_start++;
-         pp->green = *entry_start++;
-         pp->blue = *entry_start++;
-         pp->alpha = *entry_start++;
-      }
-
-      else
-      {
-         pp->red   = png_get_uint_16(entry_start); entry_start += 2;
-         pp->green = png_get_uint_16(entry_start); entry_start += 2;
-         pp->blue  = png_get_uint_16(entry_start); entry_start += 2;
-         pp->alpha = png_get_uint_16(entry_start); entry_start += 2;
-      }
-
-      pp->frequency = png_get_uint_16(entry_start); entry_start += 2;
-   }
-#else
-   pp = new_palette.entries;
-
-   for (i = 0; i < new_palette.nentries; i++)
-   {
-
-      if (new_palette.depth == 8)
-      {
-         pp[i].red   = *entry_start++;
-         pp[i].green = *entry_start++;
-         pp[i].blue  = *entry_start++;
-         pp[i].alpha = *entry_start++;
-      }
-
-      else
-      {
-         pp[i].red   = png_get_uint_16(entry_start); entry_start += 2;
-         pp[i].green = png_get_uint_16(entry_start); entry_start += 2;
-         pp[i].blue  = png_get_uint_16(entry_start); entry_start += 2;
-         pp[i].alpha = png_get_uint_16(entry_start); entry_start += 2;
-      }
-
-      pp[i].frequency = png_get_uint_16(entry_start); entry_start += 2;
-   }
-#endif
-
-   /* Discard all chunk data except the name and stash that */
-   new_palette.name = png_ptr->chunkdata;
-
-   png_set_sPLT(png_ptr, info_ptr, &new_palette, 1);
-
-   png_free(png_ptr, png_ptr->chunkdata);
-   png_ptr->chunkdata = NULL;
-   png_free(png_ptr, new_palette.entries);
-}
-#endif /* PNG_READ_sPLT_SUPPORTED */
-
-#ifdef PNG_READ_tRNS_SUPPORTED
-void /* PRIVATE */
-png_handle_tRNS(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
-{
-   png_byte readbuf[PNG_MAX_PALETTE_LENGTH];
-
-   png_debug(1, "in png_handle_tRNS");
-
-   if (!(png_ptr->mode & PNG_HAVE_IHDR))
-      dg_png_error(png_ptr, "Missing IHDR before tRNS");
-
-   else if (png_ptr->mode & PNG_HAVE_IDAT)
-   {
-      png_warning(png_ptr, "Invalid tRNS after IDAT");
-      png_crc_finish(png_ptr, length);
-      return;
-   }
-
-   else if (info_ptr != NULL && (info_ptr->valid & PNG_INFO_tRNS))
-   {
-      png_warning(png_ptr, "Duplicate tRNS chunk");
-      png_crc_finish(png_ptr, length);
-      return;
-   }
-
-   if (png_ptr->color_type == PNG_COLOR_TYPE_GRAY)
-   {
-      png_byte buf[2];
-
-      if (length != 2)
-      {
-         png_warning(png_ptr, "Incorrect tRNS chunk length");
-         png_crc_finish(png_ptr, length);
-         return;
-      }
-
-      png_crc_read(png_ptr, buf, 2);
-      png_ptr->num_trans = 1;
-      png_ptr->trans_color.gray = png_get_uint_16(buf);
-   }
-
-   else if (png_ptr->color_type == PNG_COLOR_TYPE_RGB)
-   {
-      png_byte buf[6];
-
-      if (length != 6)
-      {
-         png_warning(png_ptr, "Incorrect tRNS chunk length");
-         png_crc_finish(png_ptr, length);
-         return;
-      }
-
-      png_crc_read(png_ptr, buf, (png_size_t)length);
-      png_ptr->num_trans = 1;
-      png_ptr->trans_color.red = png_get_uint_16(buf);
-      png_ptr->trans_color.green = png_get_uint_16(buf + 2);
-      png_ptr->trans_color.blue = png_get_uint_16(buf + 4);
-   }
-
-   else if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE)
-   {
-      if (!(png_ptr->mode & PNG_HAVE_PLTE))
-      {
-         /* Should be an error, but we can cope with it. */
-         png_warning(png_ptr, "Missing PLTE before tRNS");
-      }
-
-      if (length > (png_uint_32)png_ptr->num_palette ||
-          length > PNG_MAX_PALETTE_LENGTH)
-      {
-         png_warning(png_ptr, "Incorrect tRNS chunk length");
-         png_crc_finish(png_ptr, length);
-         return;
-      }
-
-      if (length == 0)
-      {
-         png_warning(png_ptr, "Zero length tRNS chunk");
-         png_crc_finish(png_ptr, length);
-         return;
-      }
-
-      png_crc_read(png_ptr, readbuf, (png_size_t)length);
-      png_ptr->num_trans = (png_uint_16)length;
-   }
-
-   else
-   {
-      png_warning(png_ptr, "tRNS chunk not allowed with alpha channel");
-      png_crc_finish(png_ptr, length);
-      return;
-   }
-
-   if (png_crc_finish(png_ptr, 0))
-   {
-      png_ptr->num_trans = 0;
-      return;
-   }
-
-   png_set_tRNS(png_ptr, info_ptr, readbuf, png_ptr->num_trans,
-       &(png_ptr->trans_color));
-}
-#endif
-
-#ifdef PNG_READ_bKGD_SUPPORTED
-void /* PRIVATE */
-png_handle_bKGD(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
-{
-   png_size_t truelen;
-   png_byte buf[6];
-   png_color_16 background;
-
-   png_debug(1, "in png_handle_bKGD");
-
-   if (!(png_ptr->mode & PNG_HAVE_IHDR))
-      dg_png_error(png_ptr, "Missing IHDR before bKGD");
-
-   else if (png_ptr->mode & PNG_HAVE_IDAT)
-   {
-      png_warning(png_ptr, "Invalid bKGD after IDAT");
-      png_crc_finish(png_ptr, length);
-      return;
-   }
-
-   else if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE &&
-       !(png_ptr->mode & PNG_HAVE_PLTE))
-   {
-      png_warning(png_ptr, "Missing PLTE before bKGD");
-      png_crc_finish(png_ptr, length);
-      return;
-   }
-
-   else if (info_ptr != NULL && (info_ptr->valid & PNG_INFO_bKGD))
-   {
-      png_warning(png_ptr, "Duplicate bKGD chunk");
-      png_crc_finish(png_ptr, length);
-      return;
-   }
-
-   if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE)
-      truelen = 1;
-
-   else if (png_ptr->color_type & PNG_COLOR_MASK_COLOR)
-      truelen = 6;
-
-   else
-      truelen = 2;
-
-   if (length != truelen)
-   {
-      png_warning(png_ptr, "Incorrect bKGD chunk length");
-      png_crc_finish(png_ptr, length);
-      return;
-   }
-
-   png_crc_read(png_ptr, buf, truelen);
-
-   if (png_crc_finish(png_ptr, 0))
-      return;
-
-   /* We convert the index value into RGB components so that we can allow
-    * arbitrary RGB values for background when we have transparency, and
-    * so it is easy to determine the RGB values of the background color
-    * from the info_ptr struct.
-    */
-   if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE)
-   {
-      background.index = buf[0];
-
-      if (info_ptr && info_ptr->num_palette)
-      {
-         if (buf[0] >= info_ptr->num_palette)
-         {
-            png_warning(png_ptr, "Incorrect bKGD chunk index value");
-            return;
-         }
-
-         background.red = (png_uint_16)png_ptr->palette[buf[0]].red;
-         background.green = (png_uint_16)png_ptr->palette[buf[0]].green;
-         background.blue = (png_uint_16)png_ptr->palette[buf[0]].blue;
-      }
-
-      else
-         background.red = background.green = background.blue = 0;
-
-      background.gray = 0;
-   }
-
-   else if (!(png_ptr->color_type & PNG_COLOR_MASK_COLOR)) /* GRAY */
-   {
-      background.index = 0;
-      background.red =
-      background.green =
-      background.blue =
-      background.gray = png_get_uint_16(buf);
-   }
-
-   else
-   {
-      background.index = 0;
-      background.red = png_get_uint_16(buf);
-      background.green = png_get_uint_16(buf + 2);
-      background.blue = png_get_uint_16(buf + 4);
-      background.gray = 0;
-   }
-
-   png_set_bKGD(png_ptr, info_ptr, &background);
-}
-#endif
-
-#ifdef PNG_READ_hIST_SUPPORTED
-void /* PRIVATE */
-png_handle_hIST(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
-{
-   unsigned int num, i;
-   png_uint_16 readbuf[PNG_MAX_PALETTE_LENGTH];
-
-   png_debug(1, "in png_handle_hIST");
-
-   if (!(png_ptr->mode & PNG_HAVE_IHDR))
-      dg_png_error(png_ptr, "Missing IHDR before hIST");
-
-   else if (png_ptr->mode & PNG_HAVE_IDAT)
-   {
-      png_warning(png_ptr, "Invalid hIST after IDAT");
-      png_crc_finish(png_ptr, length);
-      return;
-   }
-
-   else if (!(png_ptr->mode & PNG_HAVE_PLTE))
-   {
-      png_warning(png_ptr, "Missing PLTE before hIST");
-      png_crc_finish(png_ptr, length);
-      return;
-   }
-
-   else if (info_ptr != NULL && (info_ptr->valid & PNG_INFO_hIST))
-   {
-      png_warning(png_ptr, "Duplicate hIST chunk");
-      png_crc_finish(png_ptr, length);
-      return;
-   }
-
-   if (length > 2*PNG_MAX_PALETTE_LENGTH ||
-       length != (unsigned int) (2*png_ptr->num_palette))
-   {
-      png_warning(png_ptr, "Incorrect hIST chunk length");
-      png_crc_finish(png_ptr, length);
-      return;
-   }
-
-   num = length / 2 ;
-
-   for (i = 0; i < num; i++)
-   {
-      png_byte buf[2];
-
-      png_crc_read(png_ptr, buf, 2);
-      readbuf[i] = png_get_uint_16(buf);
-   }
-
-   if (png_crc_finish(png_ptr, 0))
-      return;
-
-   png_set_hIST(png_ptr, info_ptr, readbuf);
-}
-#endif
-
-#ifdef PNG_READ_pHYs_SUPPORTED
-void /* PRIVATE */
-png_handle_pHYs(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
-{
-   png_byte buf[9];
-   png_uint_32 res_x, res_y;
-   int unit_type;
-
-   png_debug(1, "in png_handle_pHYs");
-
-   if (!(png_ptr->mode & PNG_HAVE_IHDR))
-      dg_png_error(png_ptr, "Missing IHDR before pHYs");
-
-   else if (png_ptr->mode & PNG_HAVE_IDAT)
-   {
-      png_warning(png_ptr, "Invalid pHYs after IDAT");
-      png_crc_finish(png_ptr, length);
-      return;
-   }
-
-   else if (info_ptr != NULL && (info_ptr->valid & PNG_INFO_pHYs))
-   {
-      png_warning(png_ptr, "Duplicate pHYs chunk");
-      png_crc_finish(png_ptr, length);
-      return;
-   }
-
-   if (length != 9)
-   {
-      png_warning(png_ptr, "Incorrect pHYs chunk length");
-      png_crc_finish(png_ptr, length);
-      return;
-   }
-
-   png_crc_read(png_ptr, buf, 9);
-
-   if (png_crc_finish(png_ptr, 0))
-      return;
-
-   res_x = png_get_uint_32(buf);
-   res_y = png_get_uint_32(buf + 4);
-   unit_type = buf[8];
-   png_set_pHYs(png_ptr, info_ptr, res_x, res_y, unit_type);
-}
-#endif
-
-#ifdef PNG_READ_oFFs_SUPPORTED
-void /* PRIVATE */
-png_handle_oFFs(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
-{
-   png_byte buf[9];
-   png_int_32 offset_x, offset_y;
-   int unit_type;
-
-   png_debug(1, "in png_handle_oFFs");
-
-   if (!(png_ptr->mode & PNG_HAVE_IHDR))
-      dg_png_error(png_ptr, "Missing IHDR before oFFs");
-
-   else if (png_ptr->mode & PNG_HAVE_IDAT)
-   {
-      png_warning(png_ptr, "Invalid oFFs after IDAT");
-      png_crc_finish(png_ptr, length);
-      return;
-   }
-
-   else if (info_ptr != NULL && (info_ptr->valid & PNG_INFO_oFFs))
-   {
-      png_warning(png_ptr, "Duplicate oFFs chunk");
-      png_crc_finish(png_ptr, length);
-      return;
-   }
-
-   if (length != 9)
-   {
-      png_warning(png_ptr, "Incorrect oFFs chunk length");
-      png_crc_finish(png_ptr, length);
-      return;
-   }
-
-   png_crc_read(png_ptr, buf, 9);
-
-   if (png_crc_finish(png_ptr, 0))
-      return;
-
-   offset_x = png_get_int_32(buf);
-   offset_y = png_get_int_32(buf + 4);
-   unit_type = buf[8];
-   png_set_oFFs(png_ptr, info_ptr, offset_x, offset_y, unit_type);
-}
-#endif
-
-#ifdef PNG_READ_pCAL_SUPPORTED
-/* Read the pCAL chunk (described in the PNG Extensions document) */
-void /* PRIVATE */
-png_handle_pCAL(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
-{
-   png_int_32 X0, X1;
-   png_byte type, nparams;
-   png_charp buf, units, endptr;
-   png_charpp params;
-   png_size_t slength;
-   int i;
-
-   png_debug(1, "in png_handle_pCAL");
-
-   if (!(png_ptr->mode & PNG_HAVE_IHDR))
-      dg_png_error(png_ptr, "Missing IHDR before pCAL");
-
-   else if (png_ptr->mode & PNG_HAVE_IDAT)
-   {
-      png_warning(png_ptr, "Invalid pCAL after IDAT");
-      png_crc_finish(png_ptr, length);
-      return;
-   }
-
-   else if (info_ptr != NULL && (info_ptr->valid & PNG_INFO_pCAL))
-   {
-      png_warning(png_ptr, "Duplicate pCAL chunk");
-      png_crc_finish(png_ptr, length);
-      return;
-   }
-
-   png_debug1(2, "Allocating and reading pCAL chunk data (%u bytes)",
-       length + 1);
-   png_free(png_ptr, png_ptr->chunkdata);
-   png_ptr->chunkdata = (png_charp)png_malloc_warn(png_ptr, length + 1);
-
-   if (png_ptr->chunkdata == NULL)
-   {
-      png_warning(png_ptr, "No memory for pCAL purpose");
-      return;
-   }
-
-   slength = length;
-   png_crc_read(png_ptr, (png_bytep)png_ptr->chunkdata, slength);
-
-   if (png_crc_finish(png_ptr, 0))
-   {
-      png_free(png_ptr, png_ptr->chunkdata);
-      png_ptr->chunkdata = NULL;
-      return;
-   }
-
-   png_ptr->chunkdata[slength] = 0x00; /* Null terminate the last string */
-
-   png_debug(3, "Finding end of pCAL purpose string");
-   for (buf = png_ptr->chunkdata; *buf; buf++)
-      /* Empty loop */ ;
-
-   endptr = png_ptr->chunkdata + slength;
-
-   /* We need to have at least 12 bytes after the purpose string
-    * in order to get the parameter information.
-    */
-   if (endptr <= buf + 12)
-   {
-      png_warning(png_ptr, "Invalid pCAL data");
-      png_free(png_ptr, png_ptr->chunkdata);
-      png_ptr->chunkdata = NULL;
-      return;
-   }
-
-   png_debug(3, "Reading pCAL X0, X1, type, nparams, and units");
-   X0 = png_get_int_32((png_bytep)buf+1);
-   X1 = png_get_int_32((png_bytep)buf+5);
-   type = buf[9];
-   nparams = buf[10];
-   units = buf + 11;
-
-   png_debug(3, "Checking pCAL equation type and number of parameters");
-   /* Check that we have the right number of parameters for known
-    * equation types.
-    */
-   if ((type == PNG_EQUATION_LINEAR && nparams != 2) ||
-       (type == PNG_EQUATION_BASE_E && nparams != 3) ||
-       (type == PNG_EQUATION_ARBITRARY && nparams != 3) ||
-       (type == PNG_EQUATION_HYPERBOLIC && nparams != 4))
-   {
-      png_warning(png_ptr, "Invalid pCAL parameters for equation type");
-      png_free(png_ptr, png_ptr->chunkdata);
-      png_ptr->chunkdata = NULL;
-      return;
-   }
-
-   else if (type >= PNG_EQUATION_LAST)
-   {
-      png_warning(png_ptr, "Unrecognized equation type for pCAL chunk");
-   }
-
-   for (buf = units; *buf; buf++)
-      /* Empty loop to move past the units string. */ ;
-
-   png_debug(3, "Allocating pCAL parameters array");
-
-   params = (png_charpp)png_malloc_warn(png_ptr,
-       (png_size_t)(nparams * png_sizeof(png_charp)));
-
-   if (params == NULL)
-   {
-      png_free(png_ptr, png_ptr->chunkdata);
-      png_ptr->chunkdata = NULL;
-      png_warning(png_ptr, "No memory for pCAL params");
-      return;
-   }
-
-   /* Get pointers to the start of each parameter string. */
-   for (i = 0; i < (int)nparams; i++)
-   {
-      buf++; /* Skip the null string terminator from previous parameter. */
-
-      png_debug1(3, "Reading pCAL parameter %d", i);
-
-      for (params[i] = buf; buf <= endptr && *buf != 0x00; buf++)
-         /* Empty loop to move past each parameter string */ ;
-
-      /* Make sure we haven't run out of data yet */
-      if (buf > endptr)
-      {
-         png_warning(png_ptr, "Invalid pCAL data");
-         png_free(png_ptr, png_ptr->chunkdata);
-         png_ptr->chunkdata = NULL;
-         png_free(png_ptr, params);
-         return;
-      }
-   }
-
-   png_set_pCAL(png_ptr, info_ptr, png_ptr->chunkdata, X0, X1, type, nparams,
-      units, params);
-
-   png_free(png_ptr, png_ptr->chunkdata);
-   png_ptr->chunkdata = NULL;
-   png_free(png_ptr, params);
-}
-#endif
-
-#ifdef PNG_READ_sCAL_SUPPORTED
-/* Read the sCAL chunk */
-void /* PRIVATE */
-png_handle_sCAL(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
-{
-   png_size_t slength, i;
-   int state;
-
-   png_debug(1, "in png_handle_sCAL");
-
-   if (!(png_ptr->mode & PNG_HAVE_IHDR))
-      dg_png_error(png_ptr, "Missing IHDR before sCAL");
-
-   else if (png_ptr->mode & PNG_HAVE_IDAT)
-   {
-      png_warning(png_ptr, "Invalid sCAL after IDAT");
-      png_crc_finish(png_ptr, length);
-      return;
-   }
-
-   else if (info_ptr != NULL && (info_ptr->valid & PNG_INFO_sCAL))
-   {
-      png_warning(png_ptr, "Duplicate sCAL chunk");
-      png_crc_finish(png_ptr, length);
-      return;
-   }
-
-   /* Need unit type, width, \0, height: minimum 4 bytes */
-   else if (length < 4)
-   {
-      png_warning(png_ptr, "sCAL chunk too short");
-      png_crc_finish(png_ptr, length);
-      return;
-   }
-
-   png_debug1(2, "Allocating and reading sCAL chunk data (%u bytes)",
-      length + 1);
-
-   png_ptr->chunkdata = (png_charp)png_malloc_warn(png_ptr, length + 1);
-
-   if (png_ptr->chunkdata == NULL)
-   {
-      png_warning(png_ptr, "Out of memory while processing sCAL chunk");
-      png_crc_finish(png_ptr, length);
-      return;
-   }
-
-   slength = length;
-   png_crc_read(png_ptr, (png_bytep)png_ptr->chunkdata, slength);
-   png_ptr->chunkdata[slength] = 0x00; /* Null terminate the last string */
-
-   if (png_crc_finish(png_ptr, 0))
-   {
-      png_free(png_ptr, png_ptr->chunkdata);
-      png_ptr->chunkdata = NULL;
-      return;
-   }
-
-   /* Validate the unit. */
-   if (png_ptr->chunkdata[0] != 1 && png_ptr->chunkdata[0] != 2)
-   {
-      png_warning(png_ptr, "Invalid sCAL ignored: invalid unit");
-      png_free(png_ptr, png_ptr->chunkdata);
-      png_ptr->chunkdata = NULL;
-      return;
-   }
-
-   /* Validate the ASCII numbers, need two ASCII numbers separated by
-    * a '\0' and they need to fit exactly in the chunk data.
-    */
-   i = 1;
-   state = 0;
-
-   if (!png_check_fp_number(png_ptr->chunkdata, slength, &state, &i) ||
-       i >= slength || png_ptr->chunkdata[i++] != 0)
-      png_warning(png_ptr, "Invalid sCAL chunk ignored: bad width format");
-
-   else if (!PNG_FP_IS_POSITIVE(state))
-      png_warning(png_ptr, "Invalid sCAL chunk ignored: non-positive width");
-
-   else
-   {
-      png_size_t heighti = i;
-
-      state = 0;
-      if (!png_check_fp_number(png_ptr->chunkdata, slength, &state, &i) ||
-          i != slength)
-         png_warning(png_ptr, "Invalid sCAL chunk ignored: bad height format");
-
-      else if (!PNG_FP_IS_POSITIVE(state))
-         png_warning(png_ptr,
-            "Invalid sCAL chunk ignored: non-positive height");
-
-      else
-         /* This is the (only) success case. */
-         png_set_sCAL_s(png_ptr, info_ptr, png_ptr->chunkdata[0],
-            png_ptr->chunkdata+1, png_ptr->chunkdata+heighti);
-   }
-
-   /* Clean up - just free the temporarily allocated buffer. */
-   png_free(png_ptr, png_ptr->chunkdata);
-   png_ptr->chunkdata = NULL;
-}
-#endif
-
-#ifdef PNG_READ_tIME_SUPPORTED
-void /* PRIVATE */
-png_handle_tIME(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
-{
-   png_byte buf[7];
-   png_time mod_time;
-
-   png_debug(1, "in png_handle_tIME");
-
-   if (!(png_ptr->mode & PNG_HAVE_IHDR))
-      dg_png_error(png_ptr, "Out of place tIME chunk");
-
-   else if (info_ptr != NULL && (info_ptr->valid & PNG_INFO_tIME))
-   {
-      png_warning(png_ptr, "Duplicate tIME chunk");
-      png_crc_finish(png_ptr, length);
-      return;
-   }
-
-   if (png_ptr->mode & PNG_HAVE_IDAT)
-      png_ptr->mode |= PNG_AFTER_IDAT;
-
-   if (length != 7)
-   {
-      png_warning(png_ptr, "Incorrect tIME chunk length");
-      png_crc_finish(png_ptr, length);
-      return;
-   }
-
-   png_crc_read(png_ptr, buf, 7);
-
-   if (png_crc_finish(png_ptr, 0))
-      return;
-
-   mod_time.second = buf[6];
-   mod_time.minute = buf[5];
-   mod_time.hour = buf[4];
-   mod_time.day = buf[3];
-   mod_time.month = buf[2];
-   mod_time.year = png_get_uint_16(buf);
-
-   png_set_tIME(png_ptr, info_ptr, &mod_time);
-}
-#endif
-
-#ifdef PNG_READ_tEXt_SUPPORTED
-/* Note: this does not properly handle chunks that are > 64K under DOS */
-void /* PRIVATE */
-png_handle_tEXt(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
-{
-   png_textp text_ptr;
-   png_charp key;
-   png_charp text;
-   png_uint_32 skip = 0;
-   png_size_t slength;
-   int ret;
-
-   png_debug(1, "in png_handle_tEXt");
-
-#ifdef PNG_USER_LIMITS_SUPPORTED
-   if (png_ptr->user_chunk_cache_max != 0)
-   {
-      if (png_ptr->user_chunk_cache_max == 1)
-      {
-         png_crc_finish(png_ptr, length);
-         return;
-      }
-
-      if (--png_ptr->user_chunk_cache_max == 1)
-      {
-         png_warning(png_ptr, "No space in chunk cache for tEXt");
-         png_crc_finish(png_ptr, length);
-         return;
-      }
-   }
-#endif
-
-   if (!(png_ptr->mode & PNG_HAVE_IHDR))
-      dg_png_error(png_ptr, "Missing IHDR before tEXt");
-
-   if (png_ptr->mode & PNG_HAVE_IDAT)
-      png_ptr->mode |= PNG_AFTER_IDAT;
-
-#ifdef PNG_MAX_MALLOC_64K
-   if (length > (png_uint_32)65535L)
-   {
-      png_warning(png_ptr, "tEXt chunk too large to fit in memory");
-      skip = length - (png_uint_32)65535L;
-      length = (png_uint_32)65535L;
-   }
-#endif
-
-   png_free(png_ptr, png_ptr->chunkdata);
-
-   png_ptr->chunkdata = (png_charp)png_malloc_warn(png_ptr, length + 1);
-
-   if (png_ptr->chunkdata == NULL)
-   {
-     png_warning(png_ptr, "No memory to process text chunk");
-     return;
-   }
-
-   slength = length;
-   png_crc_read(png_ptr, (png_bytep)png_ptr->chunkdata, slength);
-
-   if (png_crc_finish(png_ptr, skip))
-   {
-      png_free(png_ptr, png_ptr->chunkdata);
-      png_ptr->chunkdata = NULL;
-      return;
-   }
-
-   key = png_ptr->chunkdata;
-
-   key[slength] = 0x00;
-
-   for (text = key; *text; text++)
-      /* Empty loop to find end of key */ ;
-
-   if (text != key + slength)
-      text++;
-
-   text_ptr = (png_textp)png_malloc_warn(png_ptr,
-       png_sizeof(png_text));
-
-   if (text_ptr == NULL)
-   {
-      png_warning(png_ptr, "Not enough memory to process text chunk");
-      png_free(png_ptr, png_ptr->chunkdata);
-      png_ptr->chunkdata = NULL;
-      return;
-   }
-
-   text_ptr->compression = PNG_TEXT_COMPRESSION_NONE;
-   text_ptr->key = key;
-   text_ptr->lang = NULL;
-   text_ptr->lang_key = NULL;
-   text_ptr->itxt_length = 0;
-   text_ptr->text = text;
-   text_ptr->text_length = png_strlen(text);
-
-   ret = png_set_text_2(png_ptr, info_ptr, text_ptr, 1);
-
-   png_free(png_ptr, png_ptr->chunkdata);
-   png_ptr->chunkdata = NULL;
-   png_free(png_ptr, text_ptr);
-
-   if (ret)
-      png_warning(png_ptr, "Insufficient memory to process text chunk");
-}
-#endif
-
-#ifdef PNG_READ_zTXt_SUPPORTED
-/* Note: this does not correctly handle chunks that are > 64K under DOS */
-void /* PRIVATE */
-png_handle_zTXt(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
-{
-   png_textp text_ptr;
-   png_charp text;
-   int comp_type;
-   int ret;
-   png_size_t slength, prefix_len, data_len;
-
-   png_debug(1, "in png_handle_zTXt");
-
-#ifdef PNG_USER_LIMITS_SUPPORTED
-   if (png_ptr->user_chunk_cache_max != 0)
-   {
-      if (png_ptr->user_chunk_cache_max == 1)
-      {
-         png_crc_finish(png_ptr, length);
-         return;
-      }
-
-      if (--png_ptr->user_chunk_cache_max == 1)
-      {
-         png_warning(png_ptr, "No space in chunk cache for zTXt");
-         png_crc_finish(png_ptr, length);
-         return;
-      }
-   }
-#endif
-
-   if (!(png_ptr->mode & PNG_HAVE_IHDR))
-      dg_png_error(png_ptr, "Missing IHDR before zTXt");
-
-   if (png_ptr->mode & PNG_HAVE_IDAT)
-      png_ptr->mode |= PNG_AFTER_IDAT;
-
-#ifdef PNG_MAX_MALLOC_64K
-   /* We will no doubt have problems with chunks even half this size, but
-    * there is no hard and fast rule to tell us where to stop.
-    */
-   if (length > (png_uint_32)65535L)
-   {
-      png_warning(png_ptr, "zTXt chunk too large to fit in memory");
-      png_crc_finish(png_ptr, length);
-      return;
-   }
-#endif
-
-   png_free(png_ptr, png_ptr->chunkdata);
-   png_ptr->chunkdata = (png_charp)png_malloc_warn(png_ptr, length + 1);
-
-   if (png_ptr->chunkdata == NULL)
-   {
-      png_warning(png_ptr, "Out of memory processing zTXt chunk");
-      return;
-   }
-
-   slength = length;
-   png_crc_read(png_ptr, (png_bytep)png_ptr->chunkdata, slength);
-
-   if (png_crc_finish(png_ptr, 0))
-   {
-      png_free(png_ptr, png_ptr->chunkdata);
-      png_ptr->chunkdata = NULL;
-      return;
-   }
-
-   png_ptr->chunkdata[slength] = 0x00;
-
-   for (text = png_ptr->chunkdata; *text; text++)
-      /* Empty loop */ ;
-
-   /* zTXt must have some text after the chunkdataword */
-   if (text >= png_ptr->chunkdata + slength - 2)
-   {
-      png_warning(png_ptr, "Truncated zTXt chunk");
-      png_free(png_ptr, png_ptr->chunkdata);
-      png_ptr->chunkdata = NULL;
-      return;
-   }
-
-   else
-   {
-       comp_type = *(++text);
-
-       if (comp_type != PNG_TEXT_COMPRESSION_zTXt)
-       {
-          png_warning(png_ptr, "Unknown compression type in zTXt chunk");
-          comp_type = PNG_TEXT_COMPRESSION_zTXt;
-       }
-
-       text++;        /* Skip the compression_method byte */
-   }
-
-   prefix_len = text - png_ptr->chunkdata;
-
-   png_decompress_chunk(png_ptr, comp_type,
-       (png_size_t)length, prefix_len, &data_len);
-
-   text_ptr = (png_textp)png_malloc_warn(png_ptr,
-       png_sizeof(png_text));
-
-   if (text_ptr == NULL)
-   {
-      png_warning(png_ptr, "Not enough memory to process zTXt chunk");
-      png_free(png_ptr, png_ptr->chunkdata);
-      png_ptr->chunkdata = NULL;
-      return;
-   }
-
-   text_ptr->compression = comp_type;
-   text_ptr->key = png_ptr->chunkdata;
-   text_ptr->lang = NULL;
-   text_ptr->lang_key = NULL;
-   text_ptr->itxt_length = 0;
-   text_ptr->text = png_ptr->chunkdata + prefix_len;
-   text_ptr->text_length = data_len;
-
-   ret = png_set_text_2(png_ptr, info_ptr, text_ptr, 1);
-
-   png_free(png_ptr, text_ptr);
-   png_free(png_ptr, png_ptr->chunkdata);
-   png_ptr->chunkdata = NULL;
-
-   if (ret)
-      dg_png_error(png_ptr, "Insufficient memory to store zTXt chunk");
-}
-#endif
-
-#ifdef PNG_READ_iTXt_SUPPORTED
-/* Note: this does not correctly handle chunks that are > 64K under DOS */
-void /* PRIVATE */
-png_handle_iTXt(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
-{
-   png_textp text_ptr;
-   png_charp key, lang, text, lang_key;
-   int comp_flag;
-   int comp_type = 0;
-   int ret;
-   png_size_t slength, prefix_len, data_len;
-
-   png_debug(1, "in png_handle_iTXt");
-
-#ifdef PNG_USER_LIMITS_SUPPORTED
-   if (png_ptr->user_chunk_cache_max != 0)
-   {
-      if (png_ptr->user_chunk_cache_max == 1)
-      {
-         png_crc_finish(png_ptr, length);
-         return;
-      }
-
-      if (--png_ptr->user_chunk_cache_max == 1)
-      {
-         png_warning(png_ptr, "No space in chunk cache for iTXt");
-         png_crc_finish(png_ptr, length);
-         return;
-      }
-   }
-#endif
-
-   if (!(png_ptr->mode & PNG_HAVE_IHDR))
-      dg_png_error(png_ptr, "Missing IHDR before iTXt");
-
-   if (png_ptr->mode & PNG_HAVE_IDAT)
-      png_ptr->mode |= PNG_AFTER_IDAT;
-
-#ifdef PNG_MAX_MALLOC_64K
-   /* We will no doubt have problems with chunks even half this size, but
-    * there is no hard and fast rule to tell us where to stop.
-    */
-   if (length > (png_uint_32)65535L)
-   {
-      png_warning(png_ptr, "iTXt chunk too large to fit in memory");
-      png_crc_finish(png_ptr, length);
-      return;
-   }
-#endif
-
-   png_free(png_ptr, png_ptr->chunkdata);
-   png_ptr->chunkdata = (png_charp)png_malloc_warn(png_ptr, length + 1);
-
-   if (png_ptr->chunkdata == NULL)
-   {
-      png_warning(png_ptr, "No memory to process iTXt chunk");
-      return;
-   }
-
-   slength = length;
-   png_crc_read(png_ptr, (png_bytep)png_ptr->chunkdata, slength);
-
-   if (png_crc_finish(png_ptr, 0))
-   {
-      png_free(png_ptr, png_ptr->chunkdata);
-      png_ptr->chunkdata = NULL;
-      return;
-   }
-
-   png_ptr->chunkdata[slength] = 0x00;
-
-   for (lang = png_ptr->chunkdata; *lang; lang++)
-      /* Empty loop */ ;
-
-   lang++;        /* Skip NUL separator */
-
-   /* iTXt must have a language tag (possibly empty), two compression bytes,
-    * translated keyword (possibly empty), and possibly some text after the
-    * keyword
-    */
-
-   if (lang >= png_ptr->chunkdata + slength - 3)
-   {
-      png_warning(png_ptr, "Truncated iTXt chunk");
-      png_free(png_ptr, png_ptr->chunkdata);
-      png_ptr->chunkdata = NULL;
-      return;
-   }
-
-   else
-   {
-      comp_flag = *lang++;
-      comp_type = *lang++;
-   }
-
-   if (comp_type || (comp_flag && comp_flag != PNG_TEXT_COMPRESSION_zTXt))
-   {
-      png_warning(png_ptr, "Unknown iTXt compression type or method");
-      png_free(png_ptr, png_ptr->chunkdata);
-      png_ptr->chunkdata = NULL;
-      return;
-   }
-
-   for (lang_key = lang; *lang_key; lang_key++)
-      /* Empty loop */ ;
-
-   lang_key++;        /* Skip NUL separator */
-
-   if (lang_key >= png_ptr->chunkdata + slength)
-   {
-      png_warning(png_ptr, "Truncated iTXt chunk");
-      png_free(png_ptr, png_ptr->chunkdata);
-      png_ptr->chunkdata = NULL;
-      return;
-   }
-
-   for (text = lang_key; *text; text++)
-      /* Empty loop */ ;
-
-   text++;        /* Skip NUL separator */
-
-   if (text >= png_ptr->chunkdata + slength)
-   {
-      png_warning(png_ptr, "Malformed iTXt chunk");
-      png_free(png_ptr, png_ptr->chunkdata);
-      png_ptr->chunkdata = NULL;
-      return;
-   }
-
-   prefix_len = text - png_ptr->chunkdata;
-
-   key=png_ptr->chunkdata;
-
-   if (comp_flag)
-      png_decompress_chunk(png_ptr, comp_type,
-          (size_t)length, prefix_len, &data_len);
-
-   else
-      data_len = png_strlen(png_ptr->chunkdata + prefix_len);
-
-   text_ptr = (png_textp)png_malloc_warn(png_ptr,
-       png_sizeof(png_text));
-
-   if (text_ptr == NULL)
-   {
-      png_warning(png_ptr, "Not enough memory to process iTXt chunk");
-      png_free(png_ptr, png_ptr->chunkdata);
-      png_ptr->chunkdata = NULL;
-      return;
-   }
-
-   text_ptr->compression = (int)comp_flag + 1;
-   text_ptr->lang_key = png_ptr->chunkdata + (lang_key - key);
-   text_ptr->lang = png_ptr->chunkdata + (lang - key);
-   text_ptr->itxt_length = data_len;
-   text_ptr->text_length = 0;
-   text_ptr->key = png_ptr->chunkdata;
-   text_ptr->text = png_ptr->chunkdata + prefix_len;
-
-   ret = png_set_text_2(png_ptr, info_ptr, text_ptr, 1);
-
-   png_free(png_ptr, text_ptr);
-   png_free(png_ptr, png_ptr->chunkdata);
-   png_ptr->chunkdata = NULL;
-
-   if (ret)
-      dg_png_error(png_ptr, "Insufficient memory to store iTXt chunk");
-}
-#endif
-
-/* This function is called when we haven't found a handler for a
- * chunk.  If there isn't a problem with the chunk itself (ie bad
- * chunk name, CRC, or a critical chunk), the chunk is silently ignored
- * -- unless the PNG_FLAG_UNKNOWN_CHUNKS_SUPPORTED flag is on in which
- * case it will be saved away to be written out later.
- */
-void /* PRIVATE */
-png_handle_unknown(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
-{
-   png_uint_32 skip = 0;
-
-   png_debug(1, "in png_handle_unknown");
-
-#ifdef PNG_USER_LIMITS_SUPPORTED
-   if (png_ptr->user_chunk_cache_max != 0)
-   {
-      if (png_ptr->user_chunk_cache_max == 1)
-      {
-         png_crc_finish(png_ptr, length);
-         return;
-      }
-
-      if (--png_ptr->user_chunk_cache_max == 1)
-      {
-         png_warning(png_ptr, "No space in chunk cache for unknown chunk");
-         png_crc_finish(png_ptr, length);
-         return;
-      }
-   }
-#endif
-
-   if (png_ptr->mode & PNG_HAVE_IDAT)
-   {
-      if (png_ptr->chunk_name != png_IDAT)
-         png_ptr->mode |= PNG_AFTER_IDAT;
-   }
-
-   if (PNG_CHUNK_CRITICAL(png_ptr->chunk_name))
-   {
-#ifdef PNG_HANDLE_AS_UNKNOWN_SUPPORTED
-      if (png_chunk_unknown_handling(png_ptr, png_ptr->chunk_name) !=
-          PNG_HANDLE_CHUNK_ALWAYS
-#ifdef PNG_READ_USER_CHUNKS_SUPPORTED
-          && png_ptr->read_user_chunk_fn == NULL
-#endif
-          )
-#endif
-         png_chunk_error(png_ptr, "unknown critical chunk");
-   }
-
-#ifdef PNG_READ_UNKNOWN_CHUNKS_SUPPORTED
-   if ((png_ptr->flags & PNG_FLAG_KEEP_UNKNOWN_CHUNKS)
-#ifdef PNG_READ_USER_CHUNKS_SUPPORTED
-       || (png_ptr->read_user_chunk_fn != NULL)
-#endif
-       )
-   {
-#ifdef PNG_MAX_MALLOC_64K
-      if (length > 65535)
-      {
-         png_warning(png_ptr, "unknown chunk too large to fit in memory");
-         skip = length - 65535;
-         length = 65535;
-      }
-#endif
-
-      /* TODO: this code is very close to the unknown handling in pngpread.c,
-       * maybe it can be put into a common utility routine?
-       * png_struct::unknown_chunk is just used as a temporary variable, along
-       * with the data into which the chunk is read.  These can be eliminated.
-       */
-      PNG_CSTRING_FROM_CHUNK(png_ptr->unknown_chunk.name, png_ptr->chunk_name);
-      png_ptr->unknown_chunk.size = (png_size_t)length;
-
-      if (length == 0)
-         png_ptr->unknown_chunk.data = NULL;
-
-      else
-      {
-         png_ptr->unknown_chunk.data = (png_bytep)png_malloc(png_ptr, length);
-         png_crc_read(png_ptr, png_ptr->unknown_chunk.data, length);
-      }
-
-#ifdef PNG_READ_USER_CHUNKS_SUPPORTED
-      if (png_ptr->read_user_chunk_fn != NULL)
-      {
-         /* Callback to user unknown chunk handler */
-         int ret;
-
-         ret = (*(png_ptr->read_user_chunk_fn))
-             (png_ptr, &png_ptr->unknown_chunk);
-
-         if (ret < 0)
-            png_chunk_error(png_ptr, "error in user chunk");
-
-         if (ret == 0)
-         {
-            if (PNG_CHUNK_CRITICAL(png_ptr->chunk_name))
-            {
-#ifdef PNG_HANDLE_AS_UNKNOWN_SUPPORTED
-               if (png_chunk_unknown_handling(png_ptr, png_ptr->chunk_name) !=
-                   PNG_HANDLE_CHUNK_ALWAYS)
-#endif
-                  png_chunk_error(png_ptr, "unknown critical chunk");
-            }
-
-            png_set_unknown_chunks(png_ptr, info_ptr,
-                &png_ptr->unknown_chunk, 1);
-         }
-      }
-
-      else
-#endif
-         png_set_unknown_chunks(png_ptr, info_ptr, &png_ptr->unknown_chunk, 1);
-
-      png_free(png_ptr, png_ptr->unknown_chunk.data);
-      png_ptr->unknown_chunk.data = NULL;
-   }
-
-   else
-#endif
-      skip = length;
-
-   png_crc_finish(png_ptr, skip);
-
-#ifndef PNG_READ_USER_CHUNKS_SUPPORTED
-   PNG_UNUSED(info_ptr) /* Quiet compiler warnings about unused info_ptr */
-#endif
-}
-
-/* This function is called to verify that a chunk name is valid.
- * This function can't have the "critical chunk check" incorporated
- * into it, since in the future we will need to be able to call user
- * functions to handle unknown critical chunks after we check that
- * the chunk name itself is valid.
- */
-
-/* Bit hacking: the test for an invalid byte in the 4 byte chunk name is:
- *
- * ((c) < 65 || (c) > 122 || ((c) > 90 && (c) < 97))
- */
-
-void /* PRIVATE */
-png_check_chunk_name(png_structp png_ptr, png_uint_32 chunk_name)
-{
-   int i;
-
-   png_debug(1, "in png_check_chunk_name");
-
-   for (i=1; i<=4; ++i)
-   {
-      int c = chunk_name & 0xff;
-
-      if (c < 65 || c > 122 || (c > 90 && c < 97))
-         png_chunk_error(png_ptr, "invalid chunk type");
-
-      chunk_name >>= 8;
-   }
-}
-
-/* Combines the row recently read in with the existing pixels in the row.  This
- * routine takes care of alpha and transparency if requested.  This routine also
- * handles the two methods of progressive display of interlaced images,
- * depending on the 'display' value; if 'display' is true then the whole row
- * (dp) is filled from the start by replicating the available pixels.  If
- * 'display' is false only those pixels present in the pass are filled in.
- */
-void /* PRIVATE */
-png_combine_row(png_structp png_ptr, png_bytep dp, int display)
-{
-   unsigned int pixel_depth = png_ptr->transformed_pixel_depth;
-   png_const_bytep sp = png_ptr->row_buf + 1;
-   png_uint_32 row_width = png_ptr->width;
-   unsigned int pass = png_ptr->pass;
-   png_bytep end_ptr = 0;
-   png_byte end_byte = 0;
-   unsigned int end_mask;
-
-   png_debug(1, "in png_combine_row");
-
-   /* Added in 1.5.6: it should not be possible to enter this routine until at
-    * least one row has been read from the PNG data and transformed.
-    */
-   if (pixel_depth == 0)
-      dg_png_error(png_ptr, "internal row logic error");
-
-   /* Added in 1.5.4: the pixel depth should match the information returned by
-    * any call to png_read_update_info at this point.  Do not continue if we got
-    * this wrong.
-    */
-   if (png_ptr->info_rowbytes != 0 && png_ptr->info_rowbytes !=
-          PNG_ROWBYTES(pixel_depth, row_width))
-      dg_png_error(png_ptr, "internal row size calculation error");
-
-   /* Don't expect this to ever happen: */
-   if (row_width == 0)
-      dg_png_error(png_ptr, "internal row width error");
-
-   /* Preserve the last byte in cases where only part of it will be overwritten,
-    * the multiply below may overflow, we don't care because ANSI-C guarantees
-    * we get the low bits.
-    */
-   end_mask = (pixel_depth * row_width) & 7;
-   if (end_mask != 0)
-   {
-      /* end_ptr == NULL is a flag to say do nothing */
-      end_ptr = dp + PNG_ROWBYTES(pixel_depth, row_width) - 1;
-      end_byte = *end_ptr;
-#     ifdef PNG_READ_PACKSWAP_SUPPORTED
-         if (png_ptr->transformations & PNG_PACKSWAP) /* little-endian byte */
-            end_mask = 0xff << end_mask;
-
-         else /* big-endian byte */
-#     endif
-         end_mask = 0xff >> end_mask;
-      /* end_mask is now the bits to *keep* from the destination row */
-   }
-
-   /* For non-interlaced images this reduces to a png_memcpy(). A png_memcpy()
-    * will also happen if interlacing isn't supported or if the application
-    * does not call png_set_interlace_handling().  In the latter cases the
-    * caller just gets a sequence of the unexpanded rows from each interlace
-    * pass.
-    */
-#ifdef PNG_READ_INTERLACING_SUPPORTED
-   if (png_ptr->interlaced && (png_ptr->transformations & PNG_INTERLACE) &&
-      pass < 6 && (display == 0 ||
-      /* The following copies everything for 'display' on passes 0, 2 and 4. */
-      (display == 1 && (pass & 1) != 0)))
-   {
-      /* Narrow images may have no bits in a pass; the caller should handle
-       * this, but this test is cheap:
-       */
-      if (row_width <= PNG_PASS_START_COL(pass))
-         return;
-
-      if (pixel_depth < 8)
-      {
-         /* For pixel depths up to 4 bpp the 8-pixel mask can be expanded to fit
-          * into 32 bits, then a single loop over the bytes using the four byte
-          * values in the 32-bit mask can be used.  For the 'display' option the
-          * expanded mask may also not require any masking within a byte.  To
-          * make this work the PACKSWAP option must be taken into account - it
-          * simply requires the pixels to be reversed in each byte.
-          *
-          * The 'regular' case requires a mask for each of the first 6 passes,
-          * the 'display' case does a copy for the even passes in the range
-          * 0..6.  This has already been handled in the test above.
-          *
-          * The masks are arranged as four bytes with the first byte to use in
-          * the lowest bits (little-endian) regardless of the order (PACKSWAP or
-          * not) of the pixels in each byte.
-          *
-          * NOTE: the whole of this logic depends on the caller of this function
-          * only calling it on rows appropriate to the pass.  This function only
-          * understands the 'x' logic; the 'y' logic is handled by the caller.
-          *
-          * The following defines allow generation of compile time constant bit
-          * masks for each pixel depth and each possibility of swapped or not
-          * swapped bytes.  Pass 'p' is in the range 0..6; 'x', a pixel index,
-          * is in the range 0..7; and the result is 1 if the pixel is to be
-          * copied in the pass, 0 if not.  'S' is for the sparkle method, 'B'
-          * for the block method.
-          *
-          * With some compilers a compile time expression of the general form:
-          *
-          *    (shift >= 32) ? (a >> (shift-32)) : (b >> shift)
-          *
-          * Produces warnings with values of 'shift' in the range 33 to 63
-          * because the right hand side of the ?: expression is evaluated by
-          * the compiler even though it isn't used.  Microsoft Visual C (various
-          * versions) and the Intel C compiler are known to do this.  To avoid
-          * this the following macros are used in 1.5.6.  This is a temporary
-          * solution to avoid destabilizing the code during the release process.
-          */
-#        if PNG_USE_COMPILE_TIME_MASKS
-#           define PNG_LSR(x,s) ((x)>>((s) & 0x1f))
-#           define PNG_LSL(x,s) ((x)<<((s) & 0x1f))
-#        else
-#           define PNG_LSR(x,s) ((x)>>(s))
-#           define PNG_LSL(x,s) ((x)<<(s))
-#        endif
-#        define S_COPY(p,x) (((p)<4 ? PNG_LSR(0x80088822,(3-(p))*8+(7-(x))) :\
-           PNG_LSR(0xaa55ff00,(7-(p))*8+(7-(x)))) & 1)
-#        define B_COPY(p,x) (((p)<4 ? PNG_LSR(0xff0fff33,(3-(p))*8+(7-(x))) :\
-           PNG_LSR(0xff55ff00,(7-(p))*8+(7-(x)))) & 1)
-
-         /* Return a mask for pass 'p' pixel 'x' at depth 'd'.  The mask is
-          * little endian - the first pixel is at bit 0 - however the extra
-          * parameter 's' can be set to cause the mask position to be swapped
-          * within each byte, to match the PNG format.  This is done by XOR of
-          * the shift with 7, 6 or 4 for bit depths 1, 2 and 4.
-          */
-#        define PIXEL_MASK(p,x,d,s) \
-            (PNG_LSL(((PNG_LSL(1U,(d)))-1),(((x)*(d))^((s)?8-(d):0))))
-
-         /* Hence generate the appropriate 'block' or 'sparkle' pixel copy mask.
-          */
-#        define S_MASKx(p,x,d,s) (S_COPY(p,x)?PIXEL_MASK(p,x,d,s):0)
-#        define B_MASKx(p,x,d,s) (B_COPY(p,x)?PIXEL_MASK(p,x,d,s):0)
-
-         /* Combine 8 of these to get the full mask.  For the 1-bpp and 2-bpp
-          * cases the result needs replicating, for the 4-bpp case the above
-          * generates a full 32 bits.
-          */
-#        define MASK_EXPAND(m,d) ((m)*((d)==1?0x01010101:((d)==2?0x00010001:1)))
-
-#        define S_MASK(p,d,s) MASK_EXPAND(S_MASKx(p,0,d,s) + S_MASKx(p,1,d,s) +\
-            S_MASKx(p,2,d,s) + S_MASKx(p,3,d,s) + S_MASKx(p,4,d,s) +\
-            S_MASKx(p,5,d,s) + S_MASKx(p,6,d,s) + S_MASKx(p,7,d,s), d)
-
-#        define B_MASK(p,d,s) MASK_EXPAND(B_MASKx(p,0,d,s) + B_MASKx(p,1,d,s) +\
-            B_MASKx(p,2,d,s) + B_MASKx(p,3,d,s) + B_MASKx(p,4,d,s) +\
-            B_MASKx(p,5,d,s) + B_MASKx(p,6,d,s) + B_MASKx(p,7,d,s), d)
-
-#if PNG_USE_COMPILE_TIME_MASKS
-         /* Utility macros to construct all the masks for a depth/swap
-          * combination.  The 's' parameter says whether the format is PNG
-          * (big endian bytes) or not.  Only the three odd-numbered passes are
-          * required for the display/block algorithm.
-          */
-#        define S_MASKS(d,s) { S_MASK(0,d,s), S_MASK(1,d,s), S_MASK(2,d,s),\
-            S_MASK(3,d,s), S_MASK(4,d,s), S_MASK(5,d,s) }
-
-#        define B_MASKS(d,s) { B_MASK(1,d,s), S_MASK(3,d,s), S_MASK(5,d,s) }
-
-#        define DEPTH_INDEX(d) ((d)==1?0:((d)==2?1:2))
-
-         /* Hence the pre-compiled masks indexed by PACKSWAP (or not), depth and
-          * then pass:
-          */
-         static PNG_CONST png_uint_32 row_mask[2/*PACKSWAP*/][3/*depth*/][6] =
-         {
-            /* Little-endian byte masks for PACKSWAP */
-            { S_MASKS(1,0), S_MASKS(2,0), S_MASKS(4,0) },
-            /* Normal (big-endian byte) masks - PNG format */
-            { S_MASKS(1,1), S_MASKS(2,1), S_MASKS(4,1) }
-         };
-
-         /* display_mask has only three entries for the odd passes, so index by
-          * pass>>1.
-          */
-         static PNG_CONST png_uint_32 display_mask[2][3][3] =
-         {
-            /* Little-endian byte masks for PACKSWAP */
-            { B_MASKS(1,0), B_MASKS(2,0), B_MASKS(4,0) },
-            /* Normal (big-endian byte) masks - PNG format */
-            { B_MASKS(1,1), B_MASKS(2,1), B_MASKS(4,1) }
-         };
-
-#        define MASK(pass,depth,display,png)\
-            ((display)?display_mask[png][DEPTH_INDEX(depth)][pass>>1]:\
-               row_mask[png][DEPTH_INDEX(depth)][pass])
-
-#else /* !PNG_USE_COMPILE_TIME_MASKS */
-         /* This is the runtime alternative: it seems unlikely that this will
-          * ever be either smaller or faster than the compile time approach.
-          */
-#        define MASK(pass,depth,display,png)\
-            ((display)?B_MASK(pass,depth,png):S_MASK(pass,depth,png))
-#endif /* !PNG_USE_COMPILE_TIME_MASKS */
-
-         /* Use the appropriate mask to copy the required bits.  In some cases
-          * the byte mask will be 0 or 0xff, optimize these cases.  row_width is
-          * the number of pixels, but the code copies bytes, so it is necessary
-          * to special case the end.
-          */
-         png_uint_32 pixels_per_byte = 8 / pixel_depth;
-         png_uint_32 mask;
-
-#        ifdef PNG_READ_PACKSWAP_SUPPORTED
-            if (png_ptr->transformations & PNG_PACKSWAP)
-               mask = MASK(pass, pixel_depth, display, 0);
-
-            else
-#        endif
-            mask = MASK(pass, pixel_depth, display, 1);
-
-         for (;;)
-         {
-            png_uint_32 m;
-
-            /* It doesn't matter in the following if png_uint_32 has more than
-             * 32 bits because the high bits always match those in m<<24; it is,
-             * however, essential to use OR here, not +, because of this.
-             */
-            m = mask;
-            mask = (m >> 8) | (m << 24); /* rotate right to good compilers */
-            m &= 0xff;
-
-            if (m != 0) /* something to copy */
-            {
-               if (m != 0xff)
-                  *dp = (png_byte)((*dp & ~m) | (*sp & m));
-               else
-                  *dp = *sp;
-            }
-
-            /* NOTE: this may overwrite the last byte with garbage if the image
-             * is not an exact number of bytes wide; libpng has always done
-             * this.
-             */
-            if (row_width <= pixels_per_byte)
-               break; /* May need to restore part of the last byte */
-
-            row_width -= pixels_per_byte;
-            ++dp;
-            ++sp;
-         }
-      }
-
-      else /* pixel_depth >= 8 */
-      {
-         unsigned int bytes_to_copy, bytes_to_jump;
-
-         /* Validate the depth - it must be a multiple of 8 */
-         if (pixel_depth & 7)
-            dg_png_error(png_ptr, "invalid user transform pixel depth");
-
-         pixel_depth >>= 3; /* now in bytes */
-         row_width *= pixel_depth;
-
-         /* Regardless of pass number the Adam 7 interlace always results in a
-          * fixed number of pixels to copy then to skip.  There may be a
-          * different number of pixels to skip at the start though.
-          */
-         {
-            unsigned int offset = PNG_PASS_START_COL(pass) * pixel_depth;
-
-            row_width -= offset;
-            dp += offset;
-            sp += offset;
-         }
-
-         /* Work out the bytes to copy. */
-         if (display)
-         {
-            /* When doing the 'block' algorithm the pixel in the pass gets
-             * replicated to adjacent pixels.  This is why the even (0,2,4,6)
-             * passes are skipped above - the entire expanded row is copied.
-             */
-            bytes_to_copy = (1<<((6-pass)>>1)) * pixel_depth;
-
-            /* But don't allow this number to exceed the actual row width. */
-            if (bytes_to_copy > row_width)
-               bytes_to_copy = row_width;
-         }
-
-         else /* normal row; Adam7 only ever gives us one pixel to copy. */
-            bytes_to_copy = pixel_depth;
-
-         /* In Adam7 there is a constant offset between where the pixels go. */
-         bytes_to_jump = PNG_PASS_COL_OFFSET(pass) * pixel_depth;
-
-         /* And simply copy these bytes.  Some optimization is possible here,
-          * depending on the value of 'bytes_to_copy'.  Special case the low
-          * byte counts, which we know to be frequent.
-          *
-          * Notice that these cases all 'return' rather than 'break' - this
-          * avoids an unnecessary test on whether to restore the last byte
-          * below.
-          */
-         switch (bytes_to_copy)
-         {
-            case 1:
-               for (;;)
-               {
-                  *dp = *sp;
-
-                  if (row_width <= bytes_to_jump)
-                     return;
-
-                  dp += bytes_to_jump;
-                  sp += bytes_to_jump;
-                  row_width -= bytes_to_jump;
-               }
-
-            case 2:
-               /* There is a possibility of a partial copy at the end here; this
-                * slows the code down somewhat.
-                */
-               do
-               {
-                  dp[0] = sp[0], dp[1] = sp[1];
-
-                  if (row_width <= bytes_to_jump)
-                     return;
-
-                  sp += bytes_to_jump;
-                  dp += bytes_to_jump;
-                  row_width -= bytes_to_jump;
-               }
-               while (row_width > 1);
-
-               /* And there can only be one byte left at this point: */
-               *dp = *sp;
-               return;
-
-            case 3:
-               /* This can only be the RGB case, so each copy is exactly one
-                * pixel and it is not necessary to check for a partial copy.
-                */
-               for(;;)
-               {
-                  dp[0] = sp[0], dp[1] = sp[1], dp[2] = sp[2];
-
-                  if (row_width <= bytes_to_jump)
-                     return;
-
-                  sp += bytes_to_jump;
-                  dp += bytes_to_jump;
-                  row_width -= bytes_to_jump;
-               }
-
-            default:
-#if PNG_ALIGN_TYPE != PNG_ALIGN_NONE
-               /* Check for double byte alignment and, if possible, use a
-                * 16-bit copy.  Don't attempt this for narrow images - ones that
-                * are less than an interlace panel wide.  Don't attempt it for
-                * wide bytes_to_copy either - use the png_memcpy there.
-                */
-               if (bytes_to_copy < 16 /*else use png_memcpy*/ &&
-                  png_isaligned(dp, png_uint_16) &&
-                  png_isaligned(sp, png_uint_16) &&
-                  bytes_to_copy % sizeof (png_uint_16) == 0 &&
-                  bytes_to_jump % sizeof (png_uint_16) == 0)
-               {
-                  /* Everything is aligned for png_uint_16 copies, but try for
-                   * png_uint_32 first.
-                   */
-                  if (png_isaligned(dp, png_uint_32) &&
-                     png_isaligned(sp, png_uint_32) &&
-                     bytes_to_copy % sizeof (png_uint_32) == 0 &&
-                     bytes_to_jump % sizeof (png_uint_32) == 0)
-                  {
-                     png_uint_32p dp32 = (png_uint_32p)dp;
-                     png_const_uint_32p sp32 = (png_const_uint_32p)sp;
-                     unsigned int skip = (bytes_to_jump-bytes_to_copy) /
-                        sizeof (png_uint_32);
-
-                     do
-                     {
-                        size_t c = bytes_to_copy;
-                        do
-                        {
-                           *dp32++ = *sp32++;
-                           c -= sizeof (png_uint_32);
-                        }
-                        while (c > 0);
-
-                        if (row_width <= bytes_to_jump)
-                           return;
-
-                        dp32 += skip;
-                        sp32 += skip;
-                        row_width -= bytes_to_jump;
-                     }
-                     while (bytes_to_copy <= row_width);
-
-                     /* Get to here when the row_width truncates the final copy.
-                      * There will be 1-3 bytes left to copy, so don't try the
-                      * 16-bit loop below.
-                      */
-                     dp = (png_bytep)dp32;
-                     sp = (png_const_bytep)sp32;
-                     do
-                        *dp++ = *sp++;
-                     while (--row_width > 0);
-                     return;
-                  }
-
-                  /* Else do it in 16-bit quantities, but only if the size is
-                   * not too large.
-                   */
-                  else
-                  {
-                     png_uint_16p dp16 = (png_uint_16p)dp;
-                     png_const_uint_16p sp16 = (png_const_uint_16p)sp;
-                     unsigned int skip = (bytes_to_jump-bytes_to_copy) /
-                        sizeof (png_uint_16);
-
-                     do
-                     {
-                        size_t c = bytes_to_copy;
-                        do
-                        {
-                           *dp16++ = *sp16++;
-                           c -= sizeof (png_uint_16);
-                        }
-                        while (c > 0);
-
-                        if (row_width <= bytes_to_jump)
-                           return;
-
-                        dp16 += skip;
-                        sp16 += skip;
-                        row_width -= bytes_to_jump;
-                     }
-                     while (bytes_to_copy <= row_width);
-
-                     /* End of row - 1 byte left, bytes_to_copy > row_width: */
-                     dp = (png_bytep)dp16;
-                     sp = (png_const_bytep)sp16;
-                     do
-                        *dp++ = *sp++;
-                     while (--row_width > 0);
-                     return;
-                  }
-               }
-#endif /* PNG_ALIGN_ code */
-
-               /* The true default - use a png_memcpy: */
-               for (;;)
-               {
-                  png_memcpy(dp, sp, bytes_to_copy);
-
-                  if (row_width <= bytes_to_jump)
-                     return;
-
-                  sp += bytes_to_jump;
-                  dp += bytes_to_jump;
-                  row_width -= bytes_to_jump;
-                  if (bytes_to_copy > row_width)
-                     bytes_to_copy = row_width;
-               }
-         }
-
-         /* NOT REACHED*/
-      } /* pixel_depth >= 8 */
-
-      /* Here if pixel_depth < 8 to check 'end_ptr' below. */
-   }
-   else
-#endif
-
-   /* If here then the switch above wasn't used so just png_memcpy the whole row
-    * from the temporary row buffer (notice that this overwrites the end of the
-    * destination row if it is a partial byte.)
-    */
-   png_memcpy(dp, sp, PNG_ROWBYTES(pixel_depth, row_width));
-
-   /* Restore the overwritten bits from the last byte if necessary. */
-   if (end_ptr != NULL)
-      *end_ptr = (png_byte)((end_byte & end_mask) | (*end_ptr & ~end_mask));
-}
-
-#ifdef PNG_READ_INTERLACING_SUPPORTED
-void /* PRIVATE */
-png_do_read_interlace(png_row_infop row_info, png_bytep row, int pass,
-   png_uint_32 transformations /* Because these may affect the byte layout */)
-{
-   /* Arrays to facilitate easy interlacing - use pass (0 - 6) as index */
-   /* Offset to next interlace block */
-   static PNG_CONST int png_pass_inc[7] = {8, 8, 4, 4, 2, 2, 1};
-
-   png_debug(1, "in png_do_read_interlace");
-   if (row != NULL && row_info != NULL)
-   {
-      png_uint_32 final_width;
-
-      final_width = row_info->width * png_pass_inc[pass];
-
-      switch (row_info->pixel_depth)
-      {
-         case 1:
-         {
-            png_bytep sp = row + (png_size_t)((row_info->width - 1) >> 3);
-            png_bytep dp = row + (png_size_t)((final_width - 1) >> 3);
-            int sshift, dshift;
-            int s_start, s_end, s_inc;
-            int jstop = png_pass_inc[pass];
-            png_byte v;
-            png_uint_32 i;
-            int j;
-
-#ifdef PNG_READ_PACKSWAP_SUPPORTED
-            if (transformations & PNG_PACKSWAP)
-            {
-                sshift = (int)((row_info->width + 7) & 0x07);
-                dshift = (int)((final_width + 7) & 0x07);
-                s_start = 7;
-                s_end = 0;
-                s_inc = -1;
-            }
-
-            else
-#endif
-            {
-                sshift = 7 - (int)((row_info->width + 7) & 0x07);
-                dshift = 7 - (int)((final_width + 7) & 0x07);
-                s_start = 0;
-                s_end = 7;
-                s_inc = 1;
-            }
-
-            for (i = 0; i < row_info->width; i++)
-            {
-               v = (png_byte)((*sp >> sshift) & 0x01);
-               for (j = 0; j < jstop; j++)
-               {
-                  *dp &= (png_byte)((0x7f7f >> (7 - dshift)) & 0xff);
-                  *dp |= (png_byte)(v << dshift);
-
-                  if (dshift == s_end)
-                  {
-                     dshift = s_start;
-                     dp--;
-                  }
-
-                  else
-                     dshift += s_inc;
-               }
-
-               if (sshift == s_end)
-               {
-                  sshift = s_start;
-                  sp--;
-               }
-
-               else
-                  sshift += s_inc;
-            }
-            break;
-         }
-
-         case 2:
-         {
-            png_bytep sp = row + (png_uint_32)((row_info->width - 1) >> 2);
-            png_bytep dp = row + (png_uint_32)((final_width - 1) >> 2);
-            int sshift, dshift;
-            int s_start, s_end, s_inc;
-            int jstop = png_pass_inc[pass];
-            png_uint_32 i;
-
-#ifdef PNG_READ_PACKSWAP_SUPPORTED
-            if (transformations & PNG_PACKSWAP)
-            {
-               sshift = (int)(((row_info->width + 3) & 0x03) << 1);
-               dshift = (int)(((final_width + 3) & 0x03) << 1);
-               s_start = 6;
-               s_end = 0;
-               s_inc = -2;
-            }
-
-            else
-#endif
-            {
-               sshift = (int)((3 - ((row_info->width + 3) & 0x03)) << 1);
-               dshift = (int)((3 - ((final_width + 3) & 0x03)) << 1);
-               s_start = 0;
-               s_end = 6;
-               s_inc = 2;
-            }
-
-            for (i = 0; i < row_info->width; i++)
-            {
-               png_byte v;
-               int j;
-
-               v = (png_byte)((*sp >> sshift) & 0x03);
-               for (j = 0; j < jstop; j++)
-               {
-                  *dp &= (png_byte)((0x3f3f >> (6 - dshift)) & 0xff);
-                  *dp |= (png_byte)(v << dshift);
-
-                  if (dshift == s_end)
-                  {
-                     dshift = s_start;
-                     dp--;
-                  }
-
-                  else
-                     dshift += s_inc;
-               }
-
-               if (sshift == s_end)
-               {
-                  sshift = s_start;
-                  sp--;
-               }
-
-               else
-                  sshift += s_inc;
-            }
-            break;
-         }
-
-         case 4:
-         {
-            png_bytep sp = row + (png_size_t)((row_info->width - 1) >> 1);
-            png_bytep dp = row + (png_size_t)((final_width - 1) >> 1);
-            int sshift, dshift;
-            int s_start, s_end, s_inc;
-            png_uint_32 i;
-            int jstop = png_pass_inc[pass];
-
-#ifdef PNG_READ_PACKSWAP_SUPPORTED
-            if (transformations & PNG_PACKSWAP)
-            {
-               sshift = (int)(((row_info->width + 1) & 0x01) << 2);
-               dshift = (int)(((final_width + 1) & 0x01) << 2);
-               s_start = 4;
-               s_end = 0;
-               s_inc = -4;
-            }
-
-            else
-#endif
-            {
-               sshift = (int)((1 - ((row_info->width + 1) & 0x01)) << 2);
-               dshift = (int)((1 - ((final_width + 1) & 0x01)) << 2);
-               s_start = 0;
-               s_end = 4;
-               s_inc = 4;
-            }
-
-            for (i = 0; i < row_info->width; i++)
-            {
-               png_byte v = (png_byte)((*sp >> sshift) & 0x0f);
-               int j;
-
-               for (j = 0; j < jstop; j++)
-               {
-                  *dp &= (png_byte)((0xf0f >> (4 - dshift)) & 0xff);
-                  *dp |= (png_byte)(v << dshift);
-
-                  if (dshift == s_end)
-                  {
-                     dshift = s_start;
-                     dp--;
-                  }
-
-                  else
-                     dshift += s_inc;
-               }
-
-               if (sshift == s_end)
-               {
-                  sshift = s_start;
-                  sp--;
-               }
-
-               else
-                  sshift += s_inc;
-            }
-            break;
-         }
-
-         default:
-         {
-            png_size_t pixel_bytes = (row_info->pixel_depth >> 3);
-
-            png_bytep sp = row + (png_size_t)(row_info->width - 1)
-                * pixel_bytes;
-
-            png_bytep dp = row + (png_size_t)(final_width - 1) * pixel_bytes;
-
-            int jstop = png_pass_inc[pass];
-            png_uint_32 i;
-
-            for (i = 0; i < row_info->width; i++)
-            {
-               png_byte v[8];
-               int j;
-
-               png_memcpy(v, sp, pixel_bytes);
-
-               for (j = 0; j < jstop; j++)
-               {
-                  png_memcpy(dp, v, pixel_bytes);
-                  dp -= pixel_bytes;
-               }
-
-               sp -= pixel_bytes;
-            }
-            break;
-         }
-      }
-
-      row_info->width = final_width;
-      row_info->rowbytes = PNG_ROWBYTES(row_info->pixel_depth, final_width);
-   }
-#ifndef PNG_READ_PACKSWAP_SUPPORTED
-   PNG_UNUSED(transformations)  /* Silence compiler warning */
-#endif
-}
-#endif /* PNG_READ_INTERLACING_SUPPORTED */
-
-static void
-png_read_filter_row_sub(png_row_infop row_info, png_bytep row,
-   png_const_bytep prev_row)
-{
-   png_size_t i;
-   png_size_t istop = row_info->rowbytes;
-   unsigned int bpp = (row_info->pixel_depth + 7) >> 3;
-   png_bytep rp = row + bpp;
-
-   PNG_UNUSED(prev_row)
-
-   for (i = bpp; i < istop; i++)
-   {
-      *rp = (png_byte)(((int)(*rp) + (int)(*(rp-bpp))) & 0xff);
-      rp++;
-   }
-}
-
-static void
-png_read_filter_row_up(png_row_infop row_info, png_bytep row,
-   png_const_bytep prev_row)
-{
-   png_size_t i;
-   png_size_t istop = row_info->rowbytes;
-   png_bytep rp = row;
-   png_const_bytep pp = prev_row;
-
-   for (i = 0; i < istop; i++)
-   {
-      *rp = (png_byte)(((int)(*rp) + (int)(*pp++)) & 0xff);
-      rp++;
-   }
-}
-
-static void
-png_read_filter_row_avg(png_row_infop row_info, png_bytep row,
-   png_const_bytep prev_row)
-{
-   png_size_t i;
-   png_bytep rp = row;
-   png_const_bytep pp = prev_row;
-   unsigned int bpp = (row_info->pixel_depth + 7) >> 3;
-   png_size_t istop = row_info->rowbytes - bpp;
-
-   for (i = 0; i < bpp; i++)
-   {
-      *rp = (png_byte)(((int)(*rp) +
-         ((int)(*pp++) / 2 )) & 0xff);
-
-      rp++;
-   }
-
-   for (i = 0; i < istop; i++)
-   {
-      *rp = (png_byte)(((int)(*rp) +
-         (int)(*pp++ + *(rp-bpp)) / 2 ) & 0xff);
-
-      rp++;
-   }
-}
-
-static void
-png_read_filter_row_paeth_1byte_pixel(png_row_infop row_info, png_bytep row,
-   png_const_bytep prev_row)
-{
-   png_bytep rp_end = row + row_info->rowbytes;
-   int a, c;
-
-   /* First pixel/byte */
-   c = *prev_row++;
-   a = *row + c;
-   *row++ = (png_byte)a;
-
-   /* Remainder */
-   while (row < rp_end)
-   {
-      int b, pa, pb, pc, p;
-
-      a &= 0xff; /* From previous iteration or start */
-      b = *prev_row++;
-
-      p = b - c;
-      pc = a - c;
-
-#     ifdef PNG_USE_ABS
-         pa = abs(p);
-         pb = abs(pc);
-         pc = abs(p + pc);
-#     else
-         pa = p < 0 ? -p : p;
-         pb = pc < 0 ? -pc : pc;
-         pc = (p + pc) < 0 ? -(p + pc) : p + pc;
-#     endif
-
-      /* Find the best predictor, the least of pa, pb, pc favoring the earlier
-       * ones in the case of a tie.
-       */
-      if (pb < pa) pa = pb, a = b;
-      if (pc < pa) a = c;
-
-      /* Calculate the current pixel in a, and move the previous row pixel to c
-       * for the next time round the loop
-       */
-      c = b;
-      a += *row;
-      *row++ = (png_byte)a;
-   }
-}
-
-static void
-png_read_filter_row_paeth_multibyte_pixel(png_row_infop row_info, png_bytep row,
-   png_const_bytep prev_row)
-{
-   int bpp = (row_info->pixel_depth + 7) >> 3;
-   png_bytep rp_end = row + bpp;
-
-   /* Process the first pixel in the row completely (this is the same as 'up'
-    * because there is only one candidate predictor for the first row).
-    */
-   while (row < rp_end)
-   {
-      int a = *row + *prev_row++;
-      *row++ = (png_byte)a;
-   }
-
-   /* Remainder */
-   rp_end += row_info->rowbytes - bpp;
-
-   while (row < rp_end)
-   {
-      int a, b, c, pa, pb, pc, p;
-
-      c = *(prev_row - bpp);
-      a = *(row - bpp);
-      b = *prev_row++;
-
-      p = b - c;
-      pc = a - c;
-
-#     ifdef PNG_USE_ABS
-         pa = abs(p);
-         pb = abs(pc);
-         pc = abs(p + pc);
-#     else
-         pa = p < 0 ? -p : p;
-         pb = pc < 0 ? -pc : pc;
-         pc = (p + pc) < 0 ? -(p + pc) : p + pc;
-#     endif
-
-      if (pb < pa) pa = pb, a = b;
-      if (pc < pa) a = c;
-
-      c = b;
-      a += *row;
-      *row++ = (png_byte)a;
-   }
-}
-
-#ifdef PNG_ARM_NEON
-
-#ifdef __linux__
-#include <stdio.h>
-#include <elf.h>
-#include <asm/hwcap.h>
-
-static int png_have_hwcap(unsigned cap)
-{
-   FILE *f = fopen("/proc/self/auxv", "r");
-   Elf32_auxv_t aux;
-   int have_cap = 0;
-
-   if (!f)
-      return 0;
-
-   while (fread(&aux, sizeof(aux), 1, f) > 0)
-   {
-      if (aux.a_type == AT_HWCAP &&
-          aux.a_un.a_val & cap)
-      {
-         have_cap = 1;
-         break;
-      }
-   }
-
-   fclose(f);
-
-   return have_cap;
-}
-#endif /* __linux__ */
-
-static void
-png_init_filter_functions_neon(png_structp pp, unsigned int bpp)
-{
-#ifdef __linux__
-   if (!png_have_hwcap(HWCAP_NEON))
-      return;
-#endif
-
-   pp->read_filter[PNG_FILTER_VALUE_UP-1] = png_read_filter_row_up_neon;
-
-   if (bpp == 3)
-   {
-      pp->read_filter[PNG_FILTER_VALUE_SUB-1] = png_read_filter_row_sub3_neon;
-      pp->read_filter[PNG_FILTER_VALUE_AVG-1] = png_read_filter_row_avg3_neon;
-      pp->read_filter[PNG_FILTER_VALUE_PAETH-1] =
-         png_read_filter_row_paeth3_neon;
-   }
-
-   else if (bpp == 4)
-   {
-      pp->read_filter[PNG_FILTER_VALUE_SUB-1] = png_read_filter_row_sub4_neon;
-      pp->read_filter[PNG_FILTER_VALUE_AVG-1] = png_read_filter_row_avg4_neon;
-      pp->read_filter[PNG_FILTER_VALUE_PAETH-1] =
-          png_read_filter_row_paeth4_neon;
-   }
-}
-#endif /* PNG_ARM_NEON */
-
-static void
-png_init_filter_functions(png_structp pp)
-{
-   unsigned int bpp = (pp->pixel_depth + 7) >> 3;
-
-   pp->read_filter[PNG_FILTER_VALUE_SUB-1] = png_read_filter_row_sub;
-   pp->read_filter[PNG_FILTER_VALUE_UP-1] = png_read_filter_row_up;
-   pp->read_filter[PNG_FILTER_VALUE_AVG-1] = png_read_filter_row_avg;
-   if (bpp == 1)
-      pp->read_filter[PNG_FILTER_VALUE_PAETH-1] =
-         png_read_filter_row_paeth_1byte_pixel;
-   else
-      pp->read_filter[PNG_FILTER_VALUE_PAETH-1] =
-         png_read_filter_row_paeth_multibyte_pixel;
-
-#ifdef PNG_ARM_NEON
-   png_init_filter_functions_neon(pp, bpp);
-#endif
-}
-
-void /* PRIVATE */
-png_read_filter_row(png_structp pp, png_row_infop row_info, png_bytep row,
-   png_const_bytep prev_row, int filter)
-{
-   if (pp->read_filter[0] == NULL)
-      png_init_filter_functions(pp);
-   if (filter > PNG_FILTER_VALUE_NONE && filter < PNG_FILTER_VALUE_LAST)
-      pp->read_filter[filter-1](row_info, row, prev_row);
-}
-
-#ifdef PNG_SEQUENTIAL_READ_SUPPORTED
-void /* PRIVATE */
-png_read_finish_row(png_structp png_ptr)
-{
-#ifdef PNG_READ_INTERLACING_SUPPORTED
-   /* Arrays to facilitate easy interlacing - use pass (0 - 6) as index */
-
-   /* Start of interlace block */
-   static PNG_CONST png_byte png_pass_start[7] = {0, 4, 0, 2, 0, 1, 0};
-
-   /* Offset to next interlace block */
-   static PNG_CONST png_byte png_pass_inc[7] = {8, 8, 4, 4, 2, 2, 1};
-
-   /* Start of interlace block in the y direction */
-   static PNG_CONST png_byte png_pass_ystart[7] = {0, 0, 4, 0, 2, 0, 1};
-
-   /* Offset to next interlace block in the y direction */
-   static PNG_CONST png_byte png_pass_yinc[7] = {8, 8, 8, 4, 4, 2, 2};
-#endif /* PNG_READ_INTERLACING_SUPPORTED */
-
-   png_debug(1, "in png_read_finish_row");
-   png_ptr->row_number++;
-   if (png_ptr->row_number < png_ptr->num_rows)
-      return;
-
-#ifdef PNG_READ_INTERLACING_SUPPORTED
-   if (png_ptr->interlaced)
-   {
-      png_ptr->row_number = 0;
-
-      /* TO DO: don't do this if prev_row isn't needed (requires
-       * read-ahead of the next row's filter byte.
-       */
-      png_memset(png_ptr->prev_row, 0, png_ptr->rowbytes + 1);
-
-      do
-      {
-         png_ptr->pass++;
-
-         if (png_ptr->pass >= 7)
-            break;
-
-         png_ptr->iwidth = (png_ptr->width +
-            png_pass_inc[png_ptr->pass] - 1 -
-            png_pass_start[png_ptr->pass]) /
-            png_pass_inc[png_ptr->pass];
-
-         if (!(png_ptr->transformations & PNG_INTERLACE))
-         {
-            png_ptr->num_rows = (png_ptr->height +
-                png_pass_yinc[png_ptr->pass] - 1 -
-                png_pass_ystart[png_ptr->pass]) /
-                png_pass_yinc[png_ptr->pass];
-         }
-
-         else  /* if (png_ptr->transformations & PNG_INTERLACE) */
-            break; /* libpng deinterlacing sees every row */
-
-      } while (png_ptr->num_rows == 0 || png_ptr->iwidth == 0);
-
-      if (png_ptr->pass < 7)
-         return;
-   }
-#endif /* PNG_READ_INTERLACING_SUPPORTED */
-
-   if (!(png_ptr->flags & PNG_FLAG_ZLIB_FINISHED))
-   {
-      char extra;
-      int ret;
-
-      png_ptr->zstream.next_out = (Byte *)&extra;
-      png_ptr->zstream.avail_out = (uInt)1;
-
-      for (;;)
-      {
-         if (!(png_ptr->zstream.avail_in))
-         {
-            while (!png_ptr->idat_size)
-            {
-               png_crc_finish(png_ptr, 0);
-               png_ptr->idat_size = png_read_chunk_header(png_ptr);
-               if (png_ptr->chunk_name != png_IDAT)
-                  dg_png_error(png_ptr, "Not enough image data");
-            }
-
-            png_ptr->zstream.avail_in = (uInt)png_ptr->zbuf_size;
-            png_ptr->zstream.next_in = png_ptr->zbuf;
-
-            if (png_ptr->zbuf_size > png_ptr->idat_size)
-               png_ptr->zstream.avail_in = (uInt)png_ptr->idat_size;
-
-            png_crc_read(png_ptr, png_ptr->zbuf, png_ptr->zstream.avail_in);
-            png_ptr->idat_size -= png_ptr->zstream.avail_in;
-         }
-
-         ret = inflate(&png_ptr->zstream, Z_PARTIAL_FLUSH);
-
-         if (ret == Z_STREAM_END)
-         {
-            if (!(png_ptr->zstream.avail_out) || png_ptr->zstream.avail_in ||
-                png_ptr->idat_size)
-               png_warning(png_ptr, "Extra compressed data");
-
-            png_ptr->mode |= PNG_AFTER_IDAT;
-            png_ptr->flags |= PNG_FLAG_ZLIB_FINISHED;
-            break;
-         }
-
-         if (ret != Z_OK)
-            dg_png_error(png_ptr, png_ptr->zstream.msg ? png_ptr->zstream.msg :
-                "Decompression Error");
-
-         if (!(png_ptr->zstream.avail_out))
-         {
-            png_warning(png_ptr, "Extra compressed data");
-            png_ptr->mode |= PNG_AFTER_IDAT;
-            png_ptr->flags |= PNG_FLAG_ZLIB_FINISHED;
-            break;
-         }
-
-      }
-      png_ptr->zstream.avail_out = 0;
-   }
-
-   if (png_ptr->idat_size || png_ptr->zstream.avail_in)
-      png_warning(png_ptr, "Extra compression data");
-
-   inflateReset(&png_ptr->zstream);
-
-   png_ptr->mode |= PNG_AFTER_IDAT;
-}
-#endif /* PNG_SEQUENTIAL_READ_SUPPORTED */
-
-void /* PRIVATE */
-png_read_start_row(png_structp png_ptr)
-{
-#ifdef PNG_READ_INTERLACING_SUPPORTED
-   /* Arrays to facilitate easy interlacing - use pass (0 - 6) as index */
-
-   /* Start of interlace block */
-   static PNG_CONST png_byte png_pass_start[7] = {0, 4, 0, 2, 0, 1, 0};
-
-   /* Offset to next interlace block */
-   static PNG_CONST png_byte png_pass_inc[7] = {8, 8, 4, 4, 2, 2, 1};
-
-   /* Start of interlace block in the y direction */
-   static PNG_CONST png_byte png_pass_ystart[7] = {0, 0, 4, 0, 2, 0, 1};
-
-   /* Offset to next interlace block in the y direction */
-   static PNG_CONST png_byte png_pass_yinc[7] = {8, 8, 8, 4, 4, 2, 2};
-#endif
-
-   int max_pixel_depth;
-   png_size_t row_bytes;
-
-   png_debug(1, "in png_read_start_row");
-   png_ptr->zstream.avail_in = 0;
-#ifdef PNG_READ_TRANSFORMS_SUPPORTED
-   png_init_read_transformations(png_ptr);
-#endif
-#ifdef PNG_READ_INTERLACING_SUPPORTED
-   if (png_ptr->interlaced)
-   {
-      if (!(png_ptr->transformations & PNG_INTERLACE))
-         png_ptr->num_rows = (png_ptr->height + png_pass_yinc[0] - 1 -
-             png_pass_ystart[0]) / png_pass_yinc[0];
-
-      else
-         png_ptr->num_rows = png_ptr->height;
-
-      png_ptr->iwidth = (png_ptr->width +
-          png_pass_inc[png_ptr->pass] - 1 -
-          png_pass_start[png_ptr->pass]) /
-          png_pass_inc[png_ptr->pass];
-   }
-
-   else
-#endif /* PNG_READ_INTERLACING_SUPPORTED */
-   {
-      png_ptr->num_rows = png_ptr->height;
-      png_ptr->iwidth = png_ptr->width;
-   }
-
-   max_pixel_depth = png_ptr->pixel_depth;
-
-   /* WARNING: * png_read_transform_info (pngrtran.c) performs a simpliar set of
-    * calculations to calculate the final pixel depth, then
-    * png_do_read_transforms actually does the transforms.  This means that the
-    * code which effectively calculates this value is actually repeated in three
-    * separate places.  They must all match.  Innocent changes to the order of
-    * transformations can and will break libpng in a way that causes memory
-    * overwrites.
-    *
-    * TODO: fix this.
-    */
-#ifdef PNG_READ_PACK_SUPPORTED
-   if ((png_ptr->transformations & PNG_PACK) && png_ptr->bit_depth < 8)
-      max_pixel_depth = 8;
-#endif
-
-#ifdef PNG_READ_EXPAND_SUPPORTED
-   if (png_ptr->transformations & PNG_EXPAND)
-   {
-      if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE)
-      {
-         if (png_ptr->num_trans)
-            max_pixel_depth = 32;
-
-         else
-            max_pixel_depth = 24;
-      }
-
-      else if (png_ptr->color_type == PNG_COLOR_TYPE_GRAY)
-      {
-         if (max_pixel_depth < 8)
-            max_pixel_depth = 8;
-
-         if (png_ptr->num_trans)
-            max_pixel_depth *= 2;
-      }
-
-      else if (png_ptr->color_type == PNG_COLOR_TYPE_RGB)
-      {
-         if (png_ptr->num_trans)
-         {
-            max_pixel_depth *= 4;
-            max_pixel_depth /= 3;
-         }
-      }
-   }
-#endif
-
-#ifdef PNG_READ_EXPAND_16_SUPPORTED
-   if (png_ptr->transformations & PNG_EXPAND_16)
-   {
-#     ifdef PNG_READ_EXPAND_SUPPORTED
-         /* In fact it is an error if it isn't supported, but checking is
-          * the safe way.
-          */
-         if (png_ptr->transformations & PNG_EXPAND)
-         {
-            if (png_ptr->bit_depth < 16)
-               max_pixel_depth *= 2;
-         }
-         else
-#     endif
-         png_ptr->transformations &= ~PNG_EXPAND_16;
-   }
-#endif
-
-#ifdef PNG_READ_FILLER_SUPPORTED
-   if (png_ptr->transformations & (PNG_FILLER))
-   {
-      if (png_ptr->color_type == PNG_COLOR_TYPE_GRAY)
-      {
-         if (max_pixel_depth <= 8)
-            max_pixel_depth = 16;
-
-         else
-            max_pixel_depth = 32;
-      }
-
-      else if (png_ptr->color_type == PNG_COLOR_TYPE_RGB ||
-         png_ptr->color_type == PNG_COLOR_TYPE_PALETTE)
-      {
-         if (max_pixel_depth <= 32)
-            max_pixel_depth = 32;
-
-         else
-            max_pixel_depth = 64;
-      }
-   }
-#endif
-
-#ifdef PNG_READ_GRAY_TO_RGB_SUPPORTED
-   if (png_ptr->transformations & PNG_GRAY_TO_RGB)
-   {
-      if (
-#ifdef PNG_READ_EXPAND_SUPPORTED
-          (png_ptr->num_trans && (png_ptr->transformations & PNG_EXPAND)) ||
-#endif
-#ifdef PNG_READ_FILLER_SUPPORTED
-          (png_ptr->transformations & (PNG_FILLER)) ||
-#endif
-          png_ptr->color_type == PNG_COLOR_TYPE_GRAY_ALPHA)
-      {
-         if (max_pixel_depth <= 16)
-            max_pixel_depth = 32;
-
-         else
-            max_pixel_depth = 64;
-      }
-
-      else
-      {
-         if (max_pixel_depth <= 8)
-         {
-            if (png_ptr->color_type == PNG_COLOR_TYPE_RGB_ALPHA)
-               max_pixel_depth = 32;
-
-            else
-               max_pixel_depth = 24;
-         }
-
-         else if (png_ptr->color_type == PNG_COLOR_TYPE_RGB_ALPHA)
-            max_pixel_depth = 64;
-
-         else
-            max_pixel_depth = 48;
-      }
-   }
-#endif
-
-#if defined(PNG_READ_USER_TRANSFORM_SUPPORTED) && \
-defined(PNG_USER_TRANSFORM_PTR_SUPPORTED)
-   if (png_ptr->transformations & PNG_USER_TRANSFORM)
-   {
-      int user_pixel_depth = png_ptr->user_transform_depth *
-         png_ptr->user_transform_channels;
-
-      if (user_pixel_depth > max_pixel_depth)
-         max_pixel_depth = user_pixel_depth;
-   }
-#endif
-
-   /* This value is stored in png_struct and double checked in the row read
-    * code.
-    */
-   png_ptr->maximum_pixel_depth = (png_byte)max_pixel_depth;
-   png_ptr->transformed_pixel_depth = 0; /* calculated on demand */
-
-   /* Align the width on the next larger 8 pixels.  Mainly used
-    * for interlacing
-    */
-   row_bytes = ((png_ptr->width + 7) & ~((png_uint_32)7));
-   /* Calculate the maximum bytes needed, adding a byte and a pixel
-    * for safety's sake
-    */
-   row_bytes = PNG_ROWBYTES(max_pixel_depth, row_bytes) +
-       1 + ((max_pixel_depth + 7) >> 3);
-
-#ifdef PNG_MAX_MALLOC_64K
-   if (row_bytes > (png_uint_32)65536L)
-      dg_png_error(png_ptr, "This image requires a row greater than 64KB");
-#endif
-
-   if (row_bytes + 48 > png_ptr->old_big_row_buf_size)
-   {
-     png_free(png_ptr, png_ptr->big_row_buf);
-     png_free(png_ptr, png_ptr->big_prev_row);
-
-     if (png_ptr->interlaced)
-        png_ptr->big_row_buf = (png_bytep)png_calloc(png_ptr,
-            row_bytes + 48);
-
-     else
-        png_ptr->big_row_buf = (png_bytep)png_malloc(png_ptr, row_bytes + 48);
-
-     png_ptr->big_prev_row = (png_bytep)png_malloc(png_ptr, row_bytes + 48);
-
-#ifdef PNG_ALIGNED_MEMORY_SUPPORTED
-     /* Use 16-byte aligned memory for row_buf with at least 16 bytes
-      * of padding before and after row_buf; treat prev_row similarly.
-      * NOTE: the alignment is to the start of the pixels, one beyond the start
-      * of the buffer, because of the filter byte.  Prior to libpng 1.5.6 this
-      * was incorrect; the filter byte was aligned, which had the exact
-      * opposite effect of that intended.
-      */
-     {
-        png_bytep temp = png_ptr->big_row_buf + 32;
-        int extra = (int)((temp - (png_bytep)0) & 0x0f);
-        png_ptr->row_buf = temp - extra - 1/*filter byte*/;
-
-        temp = png_ptr->big_prev_row + 32;
-        extra = (int)((temp - (png_bytep)0) & 0x0f);
-        png_ptr->prev_row = temp - extra - 1/*filter byte*/;
-     }
-
-#else
-     /* Use 31 bytes of padding before and 17 bytes after row_buf. */
-     png_ptr->row_buf = png_ptr->big_row_buf + 31;
-     png_ptr->prev_row = png_ptr->big_prev_row + 31;
-#endif
-     png_ptr->old_big_row_buf_size = row_bytes + 48;
-   }
-
-#ifdef PNG_MAX_MALLOC_64K
-   if (png_ptr->rowbytes > 65535)
-      dg_png_error(png_ptr, "This image requires a row greater than 64KB");
-
-#endif
-   if (png_ptr->rowbytes > (PNG_SIZE_MAX - 1))
-      dg_png_error(png_ptr, "Row has too many bytes to allocate in memory");
-
-   png_memset(png_ptr->prev_row, 0, png_ptr->rowbytes + 1);
-
-   png_debug1(3, "width = %u,", png_ptr->width);
-   png_debug1(3, "height = %u,", png_ptr->height);
-   png_debug1(3, "iwidth = %u,", png_ptr->iwidth);
-   png_debug1(3, "num_rows = %u,", png_ptr->num_rows);
-   png_debug1(3, "rowbytes = %lu,", (unsigned long)png_ptr->rowbytes);
-   png_debug1(3, "irowbytes = %lu",
-       (unsigned long)PNG_ROWBYTES(png_ptr->pixel_depth, png_ptr->iwidth) + 1);
-
-   png_ptr->flags |= PNG_FLAG_ROW_INIT;
-}
-#endif /* PNG_READ_SUPPORTED */
diff --git a/plugingui/png/pngset.c b/plugingui/png/pngset.c
deleted file mode 100644
index 6395471..0000000
--- a/plugingui/png/pngset.c
+++ /dev/null
@@ -1,1311 +0,0 @@
-
-/* pngset.c - storage of image information into info struct
- *
- * Last changed in libpng 1.5.11 [June 14, 2012]
- * Copyright (c) 1998-2012 Glenn Randers-Pehrson
- * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
- * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)
- *
- * This code is released under the libpng license.
- * For conditions of distribution and use, see the disclaimer
- * and license in png.h
- *
- * The functions here are used during reads to store data from the file
- * into the info struct, and during writes to store application data
- * into the info struct for writing into the file.  This abstracts the
- * info struct and allows us to change the structure in the future.
- */
-
-#include "pngpriv.h"
-
-#if defined(PNG_READ_SUPPORTED) || defined(PNG_WRITE_SUPPORTED)
-
-#ifdef PNG_bKGD_SUPPORTED
-void PNGAPI
-png_set_bKGD(png_structp png_ptr, png_infop info_ptr,
-    png_const_color_16p background)
-{
-   png_debug1(1, "in %s storage function", "bKGD");
-
-   if (png_ptr == NULL || info_ptr == NULL)
-      return;
-
-   png_memcpy(&(info_ptr->background), background, png_sizeof(png_color_16));
-   info_ptr->valid |= PNG_INFO_bKGD;
-}
-#endif
-
-#ifdef PNG_cHRM_SUPPORTED
-void PNGFAPI
-png_set_cHRM_fixed(png_structp png_ptr, png_infop info_ptr,
-    png_fixed_point white_x, png_fixed_point white_y, png_fixed_point red_x,
-    png_fixed_point red_y, png_fixed_point green_x, png_fixed_point green_y,
-    png_fixed_point blue_x, png_fixed_point blue_y)
-{
-   png_debug1(1, "in %s storage function", "cHRM fixed");
-
-   if (png_ptr == NULL || info_ptr == NULL)
-      return;
-
-#  ifdef PNG_CHECK_cHRM_SUPPORTED
-   if (png_check_cHRM_fixed(png_ptr,
-       white_x, white_y, red_x, red_y, green_x, green_y, blue_x, blue_y))
-#  endif
-   {
-      info_ptr->x_white = white_x;
-      info_ptr->y_white = white_y;
-      info_ptr->x_red   = red_x;
-      info_ptr->y_red   = red_y;
-      info_ptr->x_green = green_x;
-      info_ptr->y_green = green_y;
-      info_ptr->x_blue  = blue_x;
-      info_ptr->y_blue  = blue_y;
-      info_ptr->valid |= PNG_INFO_cHRM;
-   }
-}
-
-void PNGFAPI
-png_set_cHRM_XYZ_fixed(png_structp png_ptr, png_infop info_ptr,
-    png_fixed_point int_red_X, png_fixed_point int_red_Y,
-    png_fixed_point int_red_Z, png_fixed_point int_green_X,
-    png_fixed_point int_green_Y, png_fixed_point int_green_Z,
-    png_fixed_point int_blue_X, png_fixed_point int_blue_Y,
-    png_fixed_point int_blue_Z)
-{
-   png_XYZ XYZ;
-   png_xy xy;
-
-   png_debug1(1, "in %s storage function", "cHRM XYZ fixed");
-
-   if (png_ptr == NULL || info_ptr == NULL)
-      return;
-
-   XYZ.redX = int_red_X;
-   XYZ.redY = int_red_Y;
-   XYZ.redZ = int_red_Z;
-   XYZ.greenX = int_green_X;
-   XYZ.greenY = int_green_Y;
-   XYZ.greenZ = int_green_Z;
-   XYZ.blueX = int_blue_X;
-   XYZ.blueY = int_blue_Y;
-   XYZ.blueZ = int_blue_Z;
-
-   if (png_xy_from_XYZ(&xy, XYZ))
-      dg_png_error(png_ptr, "XYZ values out of representable range");
-
-   png_set_cHRM_fixed(png_ptr, info_ptr, xy.whitex, xy.whitey, xy.redx, xy.redy,
-      xy.greenx, xy.greeny, xy.bluex, xy.bluey);
-}
-
-#  ifdef PNG_FLOATING_POINT_SUPPORTED
-void PNGAPI
-png_set_cHRM(png_structp png_ptr, png_infop info_ptr,
-    double white_x, double white_y, double red_x, double red_y,
-    double green_x, double green_y, double blue_x, double blue_y)
-{
-   png_set_cHRM_fixed(png_ptr, info_ptr,
-      png_fixed(png_ptr, white_x, "cHRM White X"),
-      png_fixed(png_ptr, white_y, "cHRM White Y"),
-      png_fixed(png_ptr, red_x, "cHRM Red X"),
-      png_fixed(png_ptr, red_y, "cHRM Red Y"),
-      png_fixed(png_ptr, green_x, "cHRM Green X"),
-      png_fixed(png_ptr, green_y, "cHRM Green Y"),
-      png_fixed(png_ptr, blue_x, "cHRM Blue X"),
-      png_fixed(png_ptr, blue_y, "cHRM Blue Y"));
-}
-
-void PNGAPI
-png_set_cHRM_XYZ(png_structp png_ptr, png_infop info_ptr, double red_X,
-    double red_Y, double red_Z, double green_X, double green_Y, double green_Z,
-    double blue_X, double blue_Y, double blue_Z)
-{
-   png_set_cHRM_XYZ_fixed(png_ptr, info_ptr,
-      png_fixed(png_ptr, red_X, "cHRM Red X"),
-      png_fixed(png_ptr, red_Y, "cHRM Red Y"),
-      png_fixed(png_ptr, red_Z, "cHRM Red Z"),
-      png_fixed(png_ptr, green_X, "cHRM Red X"),
-      png_fixed(png_ptr, green_Y, "cHRM Red Y"),
-      png_fixed(png_ptr, green_Z, "cHRM Red Z"),
-      png_fixed(png_ptr, blue_X, "cHRM Red X"),
-      png_fixed(png_ptr, blue_Y, "cHRM Red Y"),
-      png_fixed(png_ptr, blue_Z, "cHRM Red Z"));
-}
-#  endif /* PNG_FLOATING_POINT_SUPPORTED */
-
-#endif /* PNG_cHRM_SUPPORTED */
-
-#ifdef PNG_gAMA_SUPPORTED
-void PNGFAPI
-png_set_gAMA_fixed(png_structp png_ptr, png_infop info_ptr, png_fixed_point
-    file_gamma)
-{
-   png_debug1(1, "in %s storage function", "gAMA");
-
-   if (png_ptr == NULL || info_ptr == NULL)
-      return;
-
-   /* Changed in libpng-1.5.4 to limit the values to ensure overflow can't
-    * occur.  Since the fixed point representation is assymetrical it is
-    * possible for 1/gamma to overflow the limit of 21474 and this means the
-    * gamma value must be at least 5/100000 and hence at most 20000.0.  For
-    * safety the limits here are a little narrower.  The values are 0.00016 to
-    * 6250.0, which are truly ridiculous gamma values (and will produce
-    * displays that are all black or all white.)
-    */
-   if (file_gamma < 16 || file_gamma > 625000000)
-      png_warning(png_ptr, "Out of range gamma value ignored");
-
-   else
-   {
-      info_ptr->gamma = file_gamma;
-      info_ptr->valid |= PNG_INFO_gAMA;
-   }
-}
-
-#  ifdef PNG_FLOATING_POINT_SUPPORTED
-void PNGAPI
-png_set_gAMA(png_structp png_ptr, png_infop info_ptr, double file_gamma)
-{
-   png_set_gAMA_fixed(png_ptr, info_ptr, png_fixed(png_ptr, file_gamma,
-       "png_set_gAMA"));
-}
-#  endif
-#endif
-
-#ifdef PNG_hIST_SUPPORTED
-void PNGAPI
-png_set_hIST(png_structp png_ptr, png_infop info_ptr, png_const_uint_16p hist)
-{
-   int i;
-
-   png_debug1(1, "in %s storage function", "hIST");
-
-   if (png_ptr == NULL || info_ptr == NULL)
-      return;
-
-   if (info_ptr->num_palette == 0 || info_ptr->num_palette
-       > PNG_MAX_PALETTE_LENGTH)
-   {
-      png_warning(png_ptr,
-          "Invalid palette size, hIST allocation skipped");
-
-      return;
-   }
-
-   png_free_data(png_ptr, info_ptr, PNG_FREE_HIST, 0);
-
-   /* Changed from info->num_palette to PNG_MAX_PALETTE_LENGTH in
-    * version 1.2.1
-    */
-   png_ptr->hist = (png_uint_16p)png_malloc_warn(png_ptr,
-       PNG_MAX_PALETTE_LENGTH * png_sizeof(png_uint_16));
-
-   if (png_ptr->hist == NULL)
-   {
-      png_warning(png_ptr, "Insufficient memory for hIST chunk data");
-      return;
-   }
-
-   for (i = 0; i < info_ptr->num_palette; i++)
-      png_ptr->hist[i] = hist[i];
-
-   info_ptr->hist = png_ptr->hist;
-   info_ptr->valid |= PNG_INFO_hIST;
-   info_ptr->free_me |= PNG_FREE_HIST;
-}
-#endif
-
-void PNGAPI
-png_set_IHDR(png_structp png_ptr, png_infop info_ptr,
-    png_uint_32 width, png_uint_32 height, int bit_depth,
-    int color_type, int interlace_type, int compression_type,
-    int filter_type)
-{
-   png_debug1(1, "in %s storage function", "IHDR");
-
-   if (png_ptr == NULL || info_ptr == NULL)
-      return;
-
-   info_ptr->width = width;
-   info_ptr->height = height;
-   info_ptr->bit_depth = (png_byte)bit_depth;
-   info_ptr->color_type = (png_byte)color_type;
-   info_ptr->compression_type = (png_byte)compression_type;
-   info_ptr->filter_type = (png_byte)filter_type;
-   info_ptr->interlace_type = (png_byte)interlace_type;
-
-   png_check_IHDR (png_ptr, info_ptr->width, info_ptr->height,
-       info_ptr->bit_depth, info_ptr->color_type, info_ptr->interlace_type,
-       info_ptr->compression_type, info_ptr->filter_type);
-
-   if (info_ptr->color_type == PNG_COLOR_TYPE_PALETTE)
-      info_ptr->channels = 1;
-
-   else if (info_ptr->color_type & PNG_COLOR_MASK_COLOR)
-      info_ptr->channels = 3;
-
-   else
-      info_ptr->channels = 1;
-
-   if (info_ptr->color_type & PNG_COLOR_MASK_ALPHA)
-      info_ptr->channels++;
-
-   info_ptr->pixel_depth = (png_byte)(info_ptr->channels * info_ptr->bit_depth);
-
-   /* Check for potential overflow */
-   if (width >
-       (PNG_UINT_32_MAX >> 3)      /* 8-byte RRGGBBAA pixels */
-       - 48       /* bigrowbuf hack */
-       - 1        /* filter byte */
-       - 7*8      /* rounding of width to multiple of 8 pixels */
-       - 8)       /* extra max_pixel_depth pad */
-      info_ptr->rowbytes = 0;
-   else
-      info_ptr->rowbytes = PNG_ROWBYTES(info_ptr->pixel_depth, width);
-}
-
-#ifdef PNG_oFFs_SUPPORTED
-void PNGAPI
-png_set_oFFs(png_structp png_ptr, png_infop info_ptr,
-    png_int_32 offset_x, png_int_32 offset_y, int unit_type)
-{
-   png_debug1(1, "in %s storage function", "oFFs");
-
-   if (png_ptr == NULL || info_ptr == NULL)
-      return;
-
-   info_ptr->x_offset = offset_x;
-   info_ptr->y_offset = offset_y;
-   info_ptr->offset_unit_type = (png_byte)unit_type;
-   info_ptr->valid |= PNG_INFO_oFFs;
-}
-#endif
-
-#ifdef PNG_pCAL_SUPPORTED
-void PNGAPI
-png_set_pCAL(png_structp png_ptr, png_infop info_ptr,
-    png_const_charp purpose, png_int_32 X0, png_int_32 X1, int type,
-    int nparams, png_const_charp units, png_charpp params)
-{
-   png_size_t length;
-   int i;
-
-   png_debug1(1, "in %s storage function", "pCAL");
-
-   if (png_ptr == NULL || info_ptr == NULL)
-      return;
-
-   length = png_strlen(purpose) + 1;
-   png_debug1(3, "allocating purpose for info (%lu bytes)",
-       (unsigned long)length);
-
-   /* TODO: validate format of calibration name and unit name */
-
-   /* Check that the type matches the specification. */
-   if (type < 0 || type > 3)
-      dg_png_error(png_ptr, "Invalid pCAL equation type");
-
-   /* Validate params[nparams] */
-   for (i=0; i<nparams; ++i)
-      if (!png_check_fp_string(params[i], png_strlen(params[i])))
-         dg_png_error(png_ptr, "Invalid format for pCAL parameter");
-
-   info_ptr->pcal_purpose = (png_charp)png_malloc_warn(png_ptr, length);
-
-   if (info_ptr->pcal_purpose == NULL)
-   {
-      png_warning(png_ptr, "Insufficient memory for pCAL purpose");
-      return;
-   }
-
-   png_memcpy(info_ptr->pcal_purpose, purpose, length);
-
-   png_debug(3, "storing X0, X1, type, and nparams in info");
-   info_ptr->pcal_X0 = X0;
-   info_ptr->pcal_X1 = X1;
-   info_ptr->pcal_type = (png_byte)type;
-   info_ptr->pcal_nparams = (png_byte)nparams;
-
-   length = png_strlen(units) + 1;
-   png_debug1(3, "allocating units for info (%lu bytes)",
-     (unsigned long)length);
-
-   info_ptr->pcal_units = (png_charp)png_malloc_warn(png_ptr, length);
-
-   if (info_ptr->pcal_units == NULL)
-   {
-      png_warning(png_ptr, "Insufficient memory for pCAL units");
-      return;
-   }
-
-   png_memcpy(info_ptr->pcal_units, units, length);
-
-   info_ptr->pcal_params = (png_charpp)png_malloc_warn(png_ptr,
-       (png_size_t)((nparams + 1) * png_sizeof(png_charp)));
-
-   if (info_ptr->pcal_params == NULL)
-   {
-      png_warning(png_ptr, "Insufficient memory for pCAL params");
-      return;
-   }
-
-   png_memset(info_ptr->pcal_params, 0, (nparams + 1) * png_sizeof(png_charp));
-
-   for (i = 0; i < nparams; i++)
-   {
-      length = png_strlen(params[i]) + 1;
-      png_debug2(3, "allocating parameter %d for info (%lu bytes)", i,
-          (unsigned long)length);
-
-      info_ptr->pcal_params[i] = (png_charp)png_malloc_warn(png_ptr, length);
-
-      if (info_ptr->pcal_params[i] == NULL)
-      {
-         png_warning(png_ptr, "Insufficient memory for pCAL parameter");
-         return;
-      }
-
-      png_memcpy(info_ptr->pcal_params[i], params[i], length);
-   }
-
-   info_ptr->valid |= PNG_INFO_pCAL;
-   info_ptr->free_me |= PNG_FREE_PCAL;
-}
-#endif
-
-#ifdef PNG_sCAL_SUPPORTED
-void PNGAPI
-png_set_sCAL_s(png_structp png_ptr, png_infop info_ptr,
-    int unit, png_const_charp swidth, png_const_charp sheight)
-{
-   png_size_t lengthw = 0, lengthh = 0;
-
-   png_debug1(1, "in %s storage function", "sCAL");
-
-   if (png_ptr == NULL || info_ptr == NULL)
-      return;
-
-   /* Double check the unit (should never get here with an invalid
-    * unit unless this is an API call.)
-    */
-   if (unit != 1 && unit != 2)
-      dg_png_error(png_ptr, "Invalid sCAL unit");
-
-   if (swidth == NULL || (lengthw = png_strlen(swidth)) == 0 ||
-       swidth[0] == 45 /* '-' */ || !png_check_fp_string(swidth, lengthw))
-      dg_png_error(png_ptr, "Invalid sCAL width");
-
-   if (sheight == NULL || (lengthh = png_strlen(sheight)) == 0 ||
-       sheight[0] == 45 /* '-' */ || !png_check_fp_string(sheight, lengthh))
-      dg_png_error(png_ptr, "Invalid sCAL height");
-
-   info_ptr->scal_unit = (png_byte)unit;
-
-   ++lengthw;
-
-   png_debug1(3, "allocating unit for info (%u bytes)", (unsigned int)lengthw);
-
-   info_ptr->scal_s_width = (png_charp)png_malloc_warn(png_ptr, lengthw);
-
-   if (info_ptr->scal_s_width == NULL)
-   {
-      png_warning(png_ptr, "Memory allocation failed while processing sCAL");
-      return;
-   }
-
-   png_memcpy(info_ptr->scal_s_width, swidth, lengthw);
-
-   ++lengthh;
-
-   png_debug1(3, "allocating unit for info (%u bytes)", (unsigned int)lengthh);
-
-   info_ptr->scal_s_height = (png_charp)png_malloc_warn(png_ptr, lengthh);
-
-   if (info_ptr->scal_s_height == NULL)
-   {
-      png_free (png_ptr, info_ptr->scal_s_width);
-      info_ptr->scal_s_width = NULL;
-
-      png_warning(png_ptr, "Memory allocation failed while processing sCAL");
-      return;
-   }
-
-   png_memcpy(info_ptr->scal_s_height, sheight, lengthh);
-
-   info_ptr->valid |= PNG_INFO_sCAL;
-   info_ptr->free_me |= PNG_FREE_SCAL;
-}
-
-#  ifdef PNG_FLOATING_POINT_SUPPORTED
-void PNGAPI
-png_set_sCAL(png_structp png_ptr, png_infop info_ptr, int unit, double width,
-    double height)
-{
-   png_debug1(1, "in %s storage function", "sCAL");
-
-   /* Check the arguments. */
-   if (width <= 0)
-      png_warning(png_ptr, "Invalid sCAL width ignored");
-
-   else if (height <= 0)
-      png_warning(png_ptr, "Invalid sCAL height ignored");
-
-   else
-   {
-      /* Convert 'width' and 'height' to ASCII. */
-      char swidth[PNG_sCAL_MAX_DIGITS+1];
-      char sheight[PNG_sCAL_MAX_DIGITS+1];
-
-      png_ascii_from_fp(png_ptr, swidth, sizeof swidth, width,
-         PNG_sCAL_PRECISION);
-      png_ascii_from_fp(png_ptr, sheight, sizeof sheight, height,
-         PNG_sCAL_PRECISION);
-
-      png_set_sCAL_s(png_ptr, info_ptr, unit, swidth, sheight);
-   }
-}
-#  endif
-
-#  ifdef PNG_FIXED_POINT_SUPPORTED
-void PNGAPI
-png_set_sCAL_fixed(png_structp png_ptr, png_infop info_ptr, int unit,
-    png_fixed_point width, png_fixed_point height)
-{
-   png_debug1(1, "in %s storage function", "sCAL");
-
-   /* Check the arguments. */
-   if (width <= 0)
-      png_warning(png_ptr, "Invalid sCAL width ignored");
-
-   else if (height <= 0)
-      png_warning(png_ptr, "Invalid sCAL height ignored");
-
-   else
-   {
-      /* Convert 'width' and 'height' to ASCII. */
-      char swidth[PNG_sCAL_MAX_DIGITS+1];
-      char sheight[PNG_sCAL_MAX_DIGITS+1];
-
-      png_ascii_from_fixed(png_ptr, swidth, sizeof swidth, width);
-      png_ascii_from_fixed(png_ptr, sheight, sizeof sheight, height);
-
-      png_set_sCAL_s(png_ptr, info_ptr, unit, swidth, sheight);
-   }
-}
-#  endif
-#endif
-
-#ifdef PNG_pHYs_SUPPORTED
-void PNGAPI
-png_set_pHYs(png_structp png_ptr, png_infop info_ptr,
-    png_uint_32 res_x, png_uint_32 res_y, int unit_type)
-{
-   png_debug1(1, "in %s storage function", "pHYs");
-
-   if (png_ptr == NULL || info_ptr == NULL)
-      return;
-
-   info_ptr->x_pixels_per_unit = res_x;
-   info_ptr->y_pixels_per_unit = res_y;
-   info_ptr->phys_unit_type = (png_byte)unit_type;
-   info_ptr->valid |= PNG_INFO_pHYs;
-}
-#endif
-
-void PNGAPI
-png_set_PLTE(png_structp png_ptr, png_infop info_ptr,
-    png_const_colorp palette, int num_palette)
-{
-
-   png_debug1(1, "in %s storage function", "PLTE");
-
-   if (png_ptr == NULL || info_ptr == NULL)
-      return;
-
-   if (num_palette < 0 || num_palette > PNG_MAX_PALETTE_LENGTH)
-   {
-      if (info_ptr->color_type == PNG_COLOR_TYPE_PALETTE)
-         dg_png_error(png_ptr, "Invalid palette length");
-
-      else
-      {
-         png_warning(png_ptr, "Invalid palette length");
-         return;
-      }
-   }
-
-   /* It may not actually be necessary to set png_ptr->palette here;
-    * we do it for backward compatibility with the way the png_handle_tRNS
-    * function used to do the allocation.
-    */
-   png_free_data(png_ptr, info_ptr, PNG_FREE_PLTE, 0);
-
-   /* Changed in libpng-1.2.1 to allocate PNG_MAX_PALETTE_LENGTH instead
-    * of num_palette entries, in case of an invalid PNG file that has
-    * too-large sample values.
-    */
-   png_ptr->palette = (png_colorp)png_calloc(png_ptr,
-       PNG_MAX_PALETTE_LENGTH * png_sizeof(png_color));
-
-   png_memcpy(png_ptr->palette, palette, num_palette * png_sizeof(png_color));
-   info_ptr->palette = png_ptr->palette;
-   info_ptr->num_palette = png_ptr->num_palette = (png_uint_16)num_palette;
-
-   info_ptr->free_me |= PNG_FREE_PLTE;
-
-   info_ptr->valid |= PNG_INFO_PLTE;
-}
-
-#ifdef PNG_sBIT_SUPPORTED
-void PNGAPI
-png_set_sBIT(png_structp png_ptr, png_infop info_ptr,
-    png_const_color_8p sig_bit)
-{
-   png_debug1(1, "in %s storage function", "sBIT");
-
-   if (png_ptr == NULL || info_ptr == NULL)
-      return;
-
-   png_memcpy(&(info_ptr->sig_bit), sig_bit, png_sizeof(png_color_8));
-   info_ptr->valid |= PNG_INFO_sBIT;
-}
-#endif
-
-#ifdef PNG_sRGB_SUPPORTED
-void PNGAPI
-png_set_sRGB(png_structp png_ptr, png_infop info_ptr, int srgb_intent)
-{
-   png_debug1(1, "in %s storage function", "sRGB");
-
-   if (png_ptr == NULL || info_ptr == NULL)
-      return;
-
-   info_ptr->srgb_intent = (png_byte)srgb_intent;
-   info_ptr->valid |= PNG_INFO_sRGB;
-}
-
-void PNGAPI
-png_set_sRGB_gAMA_and_cHRM(png_structp png_ptr, png_infop info_ptr,
-    int srgb_intent)
-{
-   png_debug1(1, "in %s storage function", "sRGB_gAMA_and_cHRM");
-
-   if (png_ptr == NULL || info_ptr == NULL)
-      return;
-
-   png_set_sRGB(png_ptr, info_ptr, srgb_intent);
-
-#  ifdef PNG_gAMA_SUPPORTED
-   png_set_gAMA_fixed(png_ptr, info_ptr, PNG_GAMMA_sRGB_INVERSE);
-#  endif
-
-#  ifdef PNG_cHRM_SUPPORTED
-   png_set_cHRM_fixed(png_ptr, info_ptr,
-      /* color      x       y */
-      /* white */ 31270, 32900,
-      /* red   */ 64000, 33000,
-      /* green */ 30000, 60000,
-      /* blue  */ 15000,  6000
-   );
-#  endif /* cHRM */
-}
-#endif /* sRGB */
-
-
-#ifdef PNG_iCCP_SUPPORTED
-void PNGAPI
-png_set_iCCP(png_structp png_ptr, png_infop info_ptr,
-    png_const_charp name, int compression_type,
-    png_const_bytep profile, png_uint_32 proflen)
-{
-   png_charp new_iccp_name;
-   png_bytep new_iccp_profile;
-   png_size_t length;
-
-   png_debug1(1, "in %s storage function", "iCCP");
-
-   if (png_ptr == NULL || info_ptr == NULL || name == NULL || profile == NULL)
-      return;
-
-   length = png_strlen(name)+1;
-   new_iccp_name = (png_charp)png_malloc_warn(png_ptr, length);
-
-   if (new_iccp_name == NULL)
-   {
-        png_warning(png_ptr, "Insufficient memory to process iCCP chunk");
-      return;
-   }
-
-   png_memcpy(new_iccp_name, name, length);
-   new_iccp_profile = (png_bytep)png_malloc_warn(png_ptr, proflen);
-
-   if (new_iccp_profile == NULL)
-   {
-      png_free (png_ptr, new_iccp_name);
-      png_warning(png_ptr,
-          "Insufficient memory to process iCCP profile");
-      return;
-   }
-
-   png_memcpy(new_iccp_profile, profile, (png_size_t)proflen);
-
-   png_free_data(png_ptr, info_ptr, PNG_FREE_ICCP, 0);
-
-   info_ptr->iccp_proflen = proflen;
-   info_ptr->iccp_name = new_iccp_name;
-   info_ptr->iccp_profile = new_iccp_profile;
-   /* Compression is always zero but is here so the API and info structure
-    * does not have to change if we introduce multiple compression types
-    */
-   info_ptr->iccp_compression = (png_byte)compression_type;
-   info_ptr->free_me |= PNG_FREE_ICCP;
-   info_ptr->valid |= PNG_INFO_iCCP;
-}
-#endif
-
-#ifdef PNG_TEXT_SUPPORTED
-void PNGAPI
-png_set_text(png_structp png_ptr, png_infop info_ptr, png_const_textp text_ptr,
-    int num_text)
-{
-   int ret;
-   ret = png_set_text_2(png_ptr, info_ptr, text_ptr, num_text);
-
-   if (ret)
-      dg_png_error(png_ptr, "Insufficient memory to store text");
-}
-
-int /* PRIVATE */
-png_set_text_2(png_structp png_ptr, png_infop info_ptr,
-    png_const_textp text_ptr, int num_text)
-{
-   int i;
-
-   png_debug1(1, "in %lx storage function", png_ptr == NULL ? "unexpected" :
-      (unsigned long)png_ptr->chunk_name);
-
-   if (png_ptr == NULL || info_ptr == NULL || num_text == 0)
-      return(0);
-
-   /* Make sure we have enough space in the "text" array in info_struct
-    * to hold all of the incoming text_ptr objects.
-    */
-   if (info_ptr->num_text + num_text > info_ptr->max_text)
-   {
-      int old_max_text = info_ptr->max_text;
-      int old_num_text = info_ptr->num_text;
-
-      if (info_ptr->text != NULL)
-      {
-         png_textp old_text;
-
-         info_ptr->max_text = info_ptr->num_text + num_text + 8;
-         old_text = info_ptr->text;
-
-         info_ptr->text = (png_textp)png_malloc_warn(png_ptr,
-            (png_size_t)(info_ptr->max_text * png_sizeof(png_text)));
-
-         if (info_ptr->text == NULL)
-         {
-            /* Restore to previous condition */
-            info_ptr->max_text = old_max_text;
-            info_ptr->text = old_text;
-            return(1);
-         }
-
-         png_memcpy(info_ptr->text, old_text, (png_size_t)(old_max_text *
-             png_sizeof(png_text)));
-         png_free(png_ptr, old_text);
-      }
-
-      else
-      {
-         info_ptr->max_text = num_text + 8;
-         info_ptr->num_text = 0;
-         info_ptr->text = (png_textp)png_malloc_warn(png_ptr,
-             (png_size_t)(info_ptr->max_text * png_sizeof(png_text)));
-         if (info_ptr->text == NULL)
-         {
-            /* Restore to previous condition */
-            info_ptr->num_text = old_num_text;
-            info_ptr->max_text = old_max_text;
-            return(1);
-         }
-         info_ptr->free_me |= PNG_FREE_TEXT;
-      }
-
-      png_debug1(3, "allocated %d entries for info_ptr->text",
-          info_ptr->max_text);
-   }
-   for (i = 0; i < num_text; i++)
-   {
-      png_size_t text_length, key_len;
-      png_size_t lang_len, lang_key_len;
-      png_textp textp = &(info_ptr->text[info_ptr->num_text]);
-
-      if (text_ptr[i].key == NULL)
-          continue;
-
-      if (text_ptr[i].compression < PNG_TEXT_COMPRESSION_NONE ||
-          text_ptr[i].compression >= PNG_TEXT_COMPRESSION_LAST)
-      {
-         png_warning(png_ptr, "text compression mode is out of range");
-         continue;
-      }
-
-      key_len = png_strlen(text_ptr[i].key);
-
-      if (text_ptr[i].compression <= 0)
-      {
-         lang_len = 0;
-         lang_key_len = 0;
-      }
-
-      else
-#  ifdef PNG_iTXt_SUPPORTED
-      {
-         /* Set iTXt data */
-
-         if (text_ptr[i].lang != NULL)
-            lang_len = png_strlen(text_ptr[i].lang);
-
-         else
-            lang_len = 0;
-
-         if (text_ptr[i].lang_key != NULL)
-            lang_key_len = png_strlen(text_ptr[i].lang_key);
-
-         else
-            lang_key_len = 0;
-      }
-#  else /* PNG_iTXt_SUPPORTED */
-      {
-         png_warning(png_ptr, "iTXt chunk not supported");
-         continue;
-      }
-#  endif
-
-      if (text_ptr[i].text == NULL || text_ptr[i].text[0] == '\0')
-      {
-         text_length = 0;
-#  ifdef PNG_iTXt_SUPPORTED
-         if (text_ptr[i].compression > 0)
-            textp->compression = PNG_ITXT_COMPRESSION_NONE;
-
-         else
-#  endif
-            textp->compression = PNG_TEXT_COMPRESSION_NONE;
-      }
-
-      else
-      {
-         text_length = png_strlen(text_ptr[i].text);
-         textp->compression = text_ptr[i].compression;
-      }
-
-      textp->key = (png_charp)png_malloc_warn(png_ptr,
-          (png_size_t)
-          (key_len + text_length + lang_len + lang_key_len + 4));
-
-      if (textp->key == NULL)
-         return(1);
-
-      png_debug2(2, "Allocated %lu bytes at %p in png_set_text",
-          (unsigned long)(png_uint_32)
-          (key_len + lang_len + lang_key_len + text_length + 4),
-          textp->key);
-
-      png_memcpy(textp->key, text_ptr[i].key,(png_size_t)(key_len));
-      *(textp->key + key_len) = '\0';
-
-      if (text_ptr[i].compression > 0)
-      {
-         textp->lang = textp->key + key_len + 1;
-         png_memcpy(textp->lang, text_ptr[i].lang, lang_len);
-         *(textp->lang + lang_len) = '\0';
-         textp->lang_key = textp->lang + lang_len + 1;
-         png_memcpy(textp->lang_key, text_ptr[i].lang_key, lang_key_len);
-         *(textp->lang_key + lang_key_len) = '\0';
-         textp->text = textp->lang_key + lang_key_len + 1;
-      }
-
-      else
-      {
-         textp->lang=NULL;
-         textp->lang_key=NULL;
-         textp->text = textp->key + key_len + 1;
-      }
-
-      if (text_length)
-         png_memcpy(textp->text, text_ptr[i].text,
-             (png_size_t)(text_length));
-
-      *(textp->text + text_length) = '\0';
-
-#  ifdef PNG_iTXt_SUPPORTED
-      if (textp->compression > 0)
-      {
-         textp->text_length = 0;
-         textp->itxt_length = text_length;
-      }
-
-      else
-#  endif
-      {
-         textp->text_length = text_length;
-         textp->itxt_length = 0;
-      }
-
-      info_ptr->num_text++;
-      png_debug1(3, "transferred text chunk %d", info_ptr->num_text);
-   }
-   return(0);
-}
-#endif
-
-#ifdef PNG_tIME_SUPPORTED
-void PNGAPI
-png_set_tIME(png_structp png_ptr, png_infop info_ptr, png_const_timep mod_time)
-{
-   png_debug1(1, "in %s storage function", "tIME");
-
-   if (png_ptr == NULL || info_ptr == NULL ||
-       (png_ptr->mode & PNG_WROTE_tIME))
-      return;
-
-   if (mod_time->month == 0   || mod_time->month > 12  ||
-       mod_time->day   == 0   || mod_time->day   > 31  ||
-       mod_time->hour  > 23   || mod_time->minute > 59 ||
-       mod_time->second > 60)
-   {
-      png_warning(png_ptr, "Ignoring invalid time value");
-      return;
-   }
-
-   png_memcpy(&(info_ptr->mod_time), mod_time, png_sizeof(png_time));
-   info_ptr->valid |= PNG_INFO_tIME;
-}
-#endif
-
-#ifdef PNG_tRNS_SUPPORTED
-void PNGAPI
-png_set_tRNS(png_structp png_ptr, png_infop info_ptr,
-    png_const_bytep trans_alpha, int num_trans, png_const_color_16p trans_color)
-{
-   png_debug1(1, "in %s storage function", "tRNS");
-
-   if (png_ptr == NULL || info_ptr == NULL)
-      return;
-
-   if (trans_alpha != NULL)
-   {
-       /* It may not actually be necessary to set png_ptr->trans_alpha here;
-        * we do it for backward compatibility with the way the png_handle_tRNS
-        * function used to do the allocation.
-        */
-
-       png_free_data(png_ptr, info_ptr, PNG_FREE_TRNS, 0);
-
-       /* Changed from num_trans to PNG_MAX_PALETTE_LENGTH in version 1.2.1 */
-       png_ptr->trans_alpha = info_ptr->trans_alpha =
-           (png_bytep)png_malloc(png_ptr, (png_size_t)PNG_MAX_PALETTE_LENGTH);
-
-       if (num_trans > 0 && num_trans <= PNG_MAX_PALETTE_LENGTH)
-          png_memcpy(info_ptr->trans_alpha, trans_alpha, (png_size_t)num_trans);
-   }
-
-   if (trans_color != NULL)
-   {
-      int sample_max = (1 << info_ptr->bit_depth);
-
-      if ((info_ptr->color_type == PNG_COLOR_TYPE_GRAY &&
-          (int)trans_color->gray > sample_max) ||
-          (info_ptr->color_type == PNG_COLOR_TYPE_RGB &&
-          ((int)trans_color->red > sample_max ||
-          (int)trans_color->green > sample_max ||
-          (int)trans_color->blue > sample_max)))
-         png_warning(png_ptr,
-            "tRNS chunk has out-of-range samples for bit_depth");
-
-      png_memcpy(&(info_ptr->trans_color), trans_color,
-         png_sizeof(png_color_16));
-
-      if (num_trans == 0)
-         num_trans = 1;
-   }
-
-   info_ptr->num_trans = (png_uint_16)num_trans;
-
-   if (num_trans != 0)
-   {
-      info_ptr->valid |= PNG_INFO_tRNS;
-      info_ptr->free_me |= PNG_FREE_TRNS;
-   }
-}
-#endif
-
-#ifdef PNG_sPLT_SUPPORTED
-void PNGAPI
-png_set_sPLT(png_structp png_ptr,
-    png_infop info_ptr, png_const_sPLT_tp entries, int nentries)
-/*
- *  entries        - array of png_sPLT_t structures
- *                   to be added to the list of palettes
- *                   in the info structure.
- *
- *  nentries       - number of palette structures to be
- *                   added.
- */
-{
-   png_sPLT_tp np;
-   int i;
-
-   if (png_ptr == NULL || info_ptr == NULL)
-      return;
-
-   np = (png_sPLT_tp)png_malloc_warn(png_ptr,
-       (info_ptr->splt_palettes_num + nentries) *
-       (png_size_t)png_sizeof(png_sPLT_t));
-
-   if (np == NULL)
-   {
-      png_warning(png_ptr, "No memory for sPLT palettes");
-      return;
-   }
-
-   png_memcpy(np, info_ptr->splt_palettes,
-       info_ptr->splt_palettes_num * png_sizeof(png_sPLT_t));
-
-   png_free(png_ptr, info_ptr->splt_palettes);
-   info_ptr->splt_palettes=NULL;
-
-   for (i = 0; i < nentries; i++)
-   {
-      png_sPLT_tp to = np + info_ptr->splt_palettes_num + i;
-      png_const_sPLT_tp from = entries + i;
-      png_size_t length;
-
-      length = png_strlen(from->name) + 1;
-      to->name = (png_charp)png_malloc_warn(png_ptr, length);
-
-      if (to->name == NULL)
-      {
-         png_warning(png_ptr,
-             "Out of memory while processing sPLT chunk");
-         continue;
-      }
-
-      png_memcpy(to->name, from->name, length);
-      to->entries = (png_sPLT_entryp)png_malloc_warn(png_ptr,
-          from->nentries * png_sizeof(png_sPLT_entry));
-
-      if (to->entries == NULL)
-      {
-         png_warning(png_ptr,
-             "Out of memory while processing sPLT chunk");
-         png_free(png_ptr, to->name);
-         to->name = NULL;
-         continue;
-      }
-
-      png_memcpy(to->entries, from->entries,
-          from->nentries * png_sizeof(png_sPLT_entry));
-
-      to->nentries = from->nentries;
-      to->depth = from->depth;
-   }
-
-   info_ptr->splt_palettes = np;
-   info_ptr->splt_palettes_num += nentries;
-   info_ptr->valid |= PNG_INFO_sPLT;
-   info_ptr->free_me |= PNG_FREE_SPLT;
-}
-#endif /* PNG_sPLT_SUPPORTED */
-
-#ifdef PNG_UNKNOWN_CHUNKS_SUPPORTED
-void PNGAPI
-png_set_unknown_chunks(png_structp png_ptr,
-   png_infop info_ptr, png_const_unknown_chunkp unknowns, int num_unknowns)
-{
-   png_unknown_chunkp np;
-   int i;
-
-   if (png_ptr == NULL || info_ptr == NULL || num_unknowns == 0)
-      return;
-
-   np = (png_unknown_chunkp)png_malloc_warn(png_ptr,
-       (png_size_t)(info_ptr->unknown_chunks_num + num_unknowns) *
-       png_sizeof(png_unknown_chunk));
-
-   if (np == NULL)
-   {
-      png_warning(png_ptr,
-          "Out of memory while processing unknown chunk");
-      return;
-   }
-
-   png_memcpy(np, info_ptr->unknown_chunks,
-       (png_size_t)info_ptr->unknown_chunks_num *
-       png_sizeof(png_unknown_chunk));
-
-   png_free(png_ptr, info_ptr->unknown_chunks);
-   info_ptr->unknown_chunks = NULL;
-
-   for (i = 0; i < num_unknowns; i++)
-   {
-      png_unknown_chunkp to = np + info_ptr->unknown_chunks_num + i;
-      png_const_unknown_chunkp from = unknowns + i;
-
-      png_memcpy(to->name, from->name, png_sizeof(from->name));
-      to->name[png_sizeof(to->name)-1] = '\0';
-      to->size = from->size;
-
-      /* Note our location in the read or write sequence */
-      to->location = (png_byte)(png_ptr->mode & 0xff);
-
-      if (from->size == 0)
-         to->data=NULL;
-
-      else
-      {
-         to->data = (png_bytep)png_malloc_warn(png_ptr,
-             (png_size_t)from->size);
-
-         if (to->data == NULL)
-         {
-            png_warning(png_ptr,
-                "Out of memory while processing unknown chunk");
-            to->size = 0;
-         }
-
-         else
-            png_memcpy(to->data, from->data, from->size);
-      }
-   }
-
-   info_ptr->unknown_chunks = np;
-   info_ptr->unknown_chunks_num += num_unknowns;
-   info_ptr->free_me |= PNG_FREE_UNKN;
-}
-
-void PNGAPI
-png_set_unknown_chunk_location(png_structp png_ptr, png_infop info_ptr,
-    int chunk, int location)
-{
-   if (png_ptr != NULL && info_ptr != NULL && chunk >= 0 && chunk <
-       info_ptr->unknown_chunks_num)
-      info_ptr->unknown_chunks[chunk].location = (png_byte)location;
-}
-#endif
-
-
-#ifdef PNG_MNG_FEATURES_SUPPORTED
-png_uint_32 PNGAPI
-png_permit_mng_features (png_structp png_ptr, png_uint_32 mng_features)
-{
-   png_debug(1, "in png_permit_mng_features");
-
-   if (png_ptr == NULL)
-      return (png_uint_32)0;
-
-   png_ptr->mng_features_permitted =
-       (png_byte)(mng_features & PNG_ALL_MNG_FEATURES);
-
-   return (png_uint_32)png_ptr->mng_features_permitted;
-}
-#endif
-
-#ifdef PNG_HANDLE_AS_UNKNOWN_SUPPORTED
-void PNGAPI
-png_set_keep_unknown_chunks(png_structp png_ptr, int keep, png_const_bytep
-    chunk_list, int num_chunks)
-{
-   png_bytep new_list, p;
-   int i, old_num_chunks;
-   if (png_ptr == NULL)
-      return;
-
-   if (num_chunks == 0)
-   {
-      if (keep == PNG_HANDLE_CHUNK_ALWAYS || keep == PNG_HANDLE_CHUNK_IF_SAFE)
-         png_ptr->flags |= PNG_FLAG_KEEP_UNKNOWN_CHUNKS;
-
-      else
-         png_ptr->flags &= ~PNG_FLAG_KEEP_UNKNOWN_CHUNKS;
-
-      if (keep == PNG_HANDLE_CHUNK_ALWAYS)
-         png_ptr->flags |= PNG_FLAG_KEEP_UNSAFE_CHUNKS;
-
-      else
-         png_ptr->flags &= ~PNG_FLAG_KEEP_UNSAFE_CHUNKS;
-
-      return;
-   }
-
-   if (chunk_list == NULL)
-      return;
-
-   old_num_chunks = png_ptr->num_chunk_list;
-   new_list=(png_bytep)png_malloc(png_ptr,
-       (png_size_t)(5*(num_chunks + old_num_chunks)));
-
-   if (png_ptr->chunk_list != NULL)
-   {
-      png_memcpy(new_list, png_ptr->chunk_list,
-          (png_size_t)(5*old_num_chunks));
-      png_free(png_ptr, png_ptr->chunk_list);
-      png_ptr->chunk_list=NULL;
-   }
-
-   png_memcpy(new_list + 5*old_num_chunks, chunk_list,
-       (png_size_t)(5*num_chunks));
-
-   for (p = new_list + 5*old_num_chunks + 4, i = 0; i<num_chunks; i++, p += 5)
-      *p=(png_byte)keep;
-
-   png_ptr->num_chunk_list = old_num_chunks + num_chunks;
-   png_ptr->chunk_list = new_list;
-   png_ptr->free_me |= PNG_FREE_LIST;
-}
-#endif
-
-#ifdef PNG_READ_USER_CHUNKS_SUPPORTED
-void PNGAPI
-png_set_read_user_chunk_fn(png_structp png_ptr, png_voidp user_chunk_ptr,
-    png_user_chunk_ptr read_user_chunk_fn)
-{
-   png_debug(1, "in png_set_read_user_chunk_fn");
-
-   if (png_ptr == NULL)
-      return;
-
-   png_ptr->read_user_chunk_fn = read_user_chunk_fn;
-   png_ptr->user_chunk_ptr = user_chunk_ptr;
-}
-#endif
-
-#ifdef PNG_INFO_IMAGE_SUPPORTED
-void PNGAPI
-png_set_rows(png_structp png_ptr, png_infop info_ptr, png_bytepp row_pointers)
-{
-   png_debug1(1, "in %s storage function", "rows");
-
-   if (png_ptr == NULL || info_ptr == NULL)
-      return;
-
-   if (info_ptr->row_pointers && (info_ptr->row_pointers != row_pointers))
-      png_free_data(png_ptr, info_ptr, PNG_FREE_ROWS, 0);
-
-   info_ptr->row_pointers = row_pointers;
-
-   if (row_pointers)
-      info_ptr->valid |= PNG_INFO_IDAT;
-}
-#endif
-
-void PNGAPI
-png_set_compression_buffer_size(png_structp png_ptr, png_size_t size)
-{
-    if (png_ptr == NULL)
-       return;
-
-    png_free(png_ptr, png_ptr->zbuf);
-
-    if (size > ZLIB_IO_MAX)
-    {
-       png_warning(png_ptr, "Attempt to set buffer size beyond max ignored");
-       png_ptr->zbuf_size = ZLIB_IO_MAX;
-       size = ZLIB_IO_MAX; /* must fit */
-    }
-
-    else
-       png_ptr->zbuf_size = (uInt)size;
-
-    png_ptr->zbuf = (png_bytep)png_malloc(png_ptr, size);
-
-    /* The following ensures a relatively safe failure if this gets called while
-     * the buffer is actually in use.
-     */
-    png_ptr->zstream.next_out = png_ptr->zbuf;
-    png_ptr->zstream.avail_out = 0;
-    png_ptr->zstream.avail_in = 0;
-}
-
-void PNGAPI
-png_set_invalid(png_structp png_ptr, png_infop info_ptr, int mask)
-{
-   if (png_ptr && info_ptr)
-      info_ptr->valid &= ~mask;
-}
-
-
-
-#ifdef PNG_SET_USER_LIMITS_SUPPORTED
-/* This function was added to libpng 1.2.6 */
-void PNGAPI
-png_set_user_limits (png_structp png_ptr, png_uint_32 user_width_max,
-    png_uint_32 user_height_max)
-{
-   /* Images with dimensions larger than these limits will be
-    * rejected by png_set_IHDR().  To accept any PNG datastream
-    * regardless of dimensions, set both limits to 0x7ffffffL.
-    */
-   if (png_ptr == NULL)
-      return;
-
-   png_ptr->user_width_max = user_width_max;
-   png_ptr->user_height_max = user_height_max;
-}
-
-/* This function was added to libpng 1.4.0 */
-void PNGAPI
-png_set_chunk_cache_max (png_structp png_ptr,
-   png_uint_32 user_chunk_cache_max)
-{
-    if (png_ptr)
-       png_ptr->user_chunk_cache_max = user_chunk_cache_max;
-}
-
-/* This function was added to libpng 1.4.1 */
-void PNGAPI
-png_set_chunk_malloc_max (png_structp png_ptr,
-    png_alloc_size_t user_chunk_malloc_max)
-{
-   if (png_ptr)
-      png_ptr->user_chunk_malloc_max = user_chunk_malloc_max;
-}
-#endif /* ?PNG_SET_USER_LIMITS_SUPPORTED */
-
-
-#ifdef PNG_BENIGN_ERRORS_SUPPORTED
-void PNGAPI
-png_set_benign_errors(png_structp png_ptr, int allowed)
-{
-   png_debug(1, "in png_set_benign_errors");
-
-   if (allowed)
-      png_ptr->flags |= PNG_FLAG_BENIGN_ERRORS_WARN;
-
-   else
-      png_ptr->flags &= ~PNG_FLAG_BENIGN_ERRORS_WARN;
-}
-#endif /* PNG_BENIGN_ERRORS_SUPPORTED */
-
-#ifdef PNG_CHECK_FOR_INVALID_INDEX_SUPPORTED
-/* Whether to report invalid palette index; added at libng-1.5.10
- *   allowed  - one of 0: disable; 1: enable
- */
-void PNGAPI
-png_set_check_for_invalid_index(png_structp png_ptr, int allowed)
-{
-   png_debug(1, "in png_set_check_for_invalid_index");
-
-   if (allowed)
-      png_ptr->num_palette_max = 0;
-
-   else
-      png_ptr->num_palette_max = -1;
-}
-#endif
-
-#endif /* PNG_READ_SUPPORTED || PNG_WRITE_SUPPORTED */
diff --git a/plugingui/png/pngstruct.h b/plugingui/png/pngstruct.h
deleted file mode 100644
index db0d4e4..0000000
--- a/plugingui/png/pngstruct.h
+++ /dev/null
@@ -1,358 +0,0 @@
-
-/* pngstruct.h - header file for PNG reference library
- *
- * Copyright (c) 1998-2012 Glenn Randers-Pehrson
- * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
- * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)
- *
- * Last changed in libpng 1.5.9 [February 18, 2012]
- *
- * This code is released under the libpng license.
- * For conditions of distribution and use, see the disclaimer
- * and license in png.h
- */
-
-/* The structure that holds the information to read and write PNG files.
- * The only people who need to care about what is inside of this are the
- * people who will be modifying the library for their own special needs.
- * It should NOT be accessed directly by an application.
- */
-
-#ifndef PNGSTRUCT_H
-#define PNGSTRUCT_H
-/* zlib.h defines the structure z_stream, an instance of which is included
- * in this structure and is required for decompressing the LZ compressed
- * data in PNG files.
- */
-#include "zlib.h"
-
-struct png_struct_def
-{
-#ifdef PNG_SETJMP_SUPPORTED
-   jmp_buf longjmp_buffer;    /* used in png_error */
-   png_longjmp_ptr longjmp_fn;/* setjmp non-local goto function. */
-#endif
-   png_error_ptr error_fn;    /* function for printing errors and aborting */
-#ifdef PNG_WARNINGS_SUPPORTED
-   png_error_ptr warning_fn;  /* function for printing warnings */
-#endif
-   png_voidp error_ptr;       /* user supplied struct for error functions */
-   png_rw_ptr write_data_fn;  /* function for writing output data */
-   png_rw_ptr read_data_fn;   /* function for reading input data */
-   png_voidp io_ptr;          /* ptr to application struct for I/O functions */
-
-#ifdef PNG_READ_USER_TRANSFORM_SUPPORTED
-   png_user_transform_ptr read_user_transform_fn; /* user read transform */
-#endif
-
-#ifdef PNG_WRITE_USER_TRANSFORM_SUPPORTED
-   png_user_transform_ptr write_user_transform_fn; /* user write transform */
-#endif
-
-/* These were added in libpng-1.0.2 */
-#ifdef PNG_USER_TRANSFORM_PTR_SUPPORTED
-#if defined(PNG_READ_USER_TRANSFORM_SUPPORTED) || \
-    defined(PNG_WRITE_USER_TRANSFORM_SUPPORTED)
-   png_voidp user_transform_ptr; /* user supplied struct for user transform */
-   png_byte user_transform_depth;    /* bit depth of user transformed pixels */
-   png_byte user_transform_channels; /* channels in user transformed pixels */
-#endif
-#endif
-
-   png_uint_32 mode;          /* tells us where we are in the PNG file */
-   png_uint_32 flags;         /* flags indicating various things to libpng */
-   png_uint_32 transformations; /* which transformations to perform */
-
-   z_stream zstream;          /* pointer to decompression structure (below) */
-   png_bytep zbuf;            /* buffer for zlib */
-   uInt zbuf_size;            /* size of zbuf (typically 65536) */
-#ifdef PNG_WRITE_SUPPORTED
-
-/* Added in 1.5.4: state to keep track of whether the zstream has been
- * initialized and if so whether it is for IDAT or some other chunk.
- */
-#define PNG_ZLIB_UNINITIALIZED 0
-#define PNG_ZLIB_FOR_IDAT      1
-#define PNG_ZLIB_FOR_TEXT      2 /* anything other than IDAT */
-#define PNG_ZLIB_USE_MASK      3 /* bottom two bits */
-#define PNG_ZLIB_IN_USE        4 /* a flag value */
-
-   png_uint_32 zlib_state;       /* State of zlib initialization */
-/* End of material added at libpng 1.5.4 */
-
-   int zlib_level;            /* holds zlib compression level */
-   int zlib_method;           /* holds zlib compression method */
-   int zlib_window_bits;      /* holds zlib compression window bits */
-   int zlib_mem_level;        /* holds zlib compression memory level */
-   int zlib_strategy;         /* holds zlib compression strategy */
-#endif
-/* Added at libpng 1.5.4 */
-#if defined(PNG_WRITE_COMPRESSED_TEXT_SUPPORTED) || \
-    defined(PNG_WRITE_CUSTOMIZE_ZTXT_COMPRESSION_SUPPORTED)
-   int zlib_text_level;            /* holds zlib compression level */
-   int zlib_text_method;           /* holds zlib compression method */
-   int zlib_text_window_bits;      /* holds zlib compression window bits */
-   int zlib_text_mem_level;        /* holds zlib compression memory level */
-   int zlib_text_strategy;         /* holds zlib compression strategy */
-#endif
-/* End of material added at libpng 1.5.4 */
-
-   png_uint_32 width;         /* width of image in pixels */
-   png_uint_32 height;        /* height of image in pixels */
-   png_uint_32 num_rows;      /* number of rows in current pass */
-   png_uint_32 usr_width;     /* width of row at start of write */
-   png_size_t rowbytes;       /* size of row in bytes */
-   png_uint_32 iwidth;        /* width of current interlaced row in pixels */
-   png_uint_32 row_number;    /* current row in interlace pass */
-   png_uint_32 chunk_name;    /* PNG_CHUNK() id of current chunk */
-   png_bytep prev_row;        /* buffer to save previous (unfiltered) row.
-                               * This is a pointer into big_prev_row
-                               */
-   png_bytep row_buf;         /* buffer to save current (unfiltered) row.
-                               * This is a pointer into big_row_buf
-                               */
-   png_bytep sub_row;         /* buffer to save "sub" row when filtering */
-   png_bytep up_row;          /* buffer to save "up" row when filtering */
-   png_bytep avg_row;         /* buffer to save "avg" row when filtering */
-   png_bytep paeth_row;       /* buffer to save "Paeth" row when filtering */
-   png_size_t info_rowbytes;  /* Added in 1.5.4: cache of updated row bytes */
-
-   png_uint_32 idat_size;     /* current IDAT size for read */
-   png_uint_32 crc;           /* current chunk CRC value */
-   png_colorp palette;        /* palette from the input file */
-   png_uint_16 num_palette;   /* number of color entries in palette */
-
-/* Added at libpng-1.5.10 */
-#ifdef PNG_CHECK_FOR_INVALID_INDEX_SUPPORTED
-   int num_palette_max;       /* maximum palette index found in IDAT */
-#endif
-
-   png_uint_16 num_trans;     /* number of transparency values */
-   png_byte compression;      /* file compression type (always 0) */
-   png_byte filter;           /* file filter type (always 0) */
-   png_byte interlaced;       /* PNG_INTERLACE_NONE, PNG_INTERLACE_ADAM7 */
-   png_byte pass;             /* current interlace pass (0 - 6) */
-   png_byte do_filter;        /* row filter flags (see PNG_FILTER_ below ) */
-   png_byte color_type;       /* color type of file */
-   png_byte bit_depth;        /* bit depth of file */
-   png_byte usr_bit_depth;    /* bit depth of users row: write only */
-   png_byte pixel_depth;      /* number of bits per pixel */
-   png_byte channels;         /* number of channels in file */
-   png_byte usr_channels;     /* channels at start of write: write only */
-   png_byte sig_bytes;        /* magic bytes read/written from start of file */
-   png_byte maximum_pixel_depth;
-                              /* pixel depth used for the row buffers */
-   png_byte transformed_pixel_depth;
-                              /* pixel depth after read/write transforms */
-   png_byte io_chunk_string[5];
-                              /* string name of chunk */
-
-#if defined(PNG_READ_FILLER_SUPPORTED) || defined(PNG_WRITE_FILLER_SUPPORTED)
-   png_uint_16 filler;           /* filler bytes for pixel expansion */
-#endif
-
-#if defined(PNG_bKGD_SUPPORTED) || defined(PNG_READ_BACKGROUND_SUPPORTED) ||\
-   defined(PNG_READ_ALPHA_MODE_SUPPORTED)
-   png_byte background_gamma_type;
-   png_fixed_point background_gamma;
-   png_color_16 background;   /* background color in screen gamma space */
-#ifdef PNG_READ_GAMMA_SUPPORTED
-   png_color_16 background_1; /* background normalized to gamma 1.0 */
-#endif
-#endif /* PNG_bKGD_SUPPORTED */
-
-#ifdef PNG_WRITE_FLUSH_SUPPORTED
-   png_flush_ptr output_flush_fn; /* Function for flushing output */
-   png_uint_32 flush_dist;    /* how many rows apart to flush, 0 - no flush */
-   png_uint_32 flush_rows;    /* number of rows written since last flush */
-#endif
-
-#ifdef PNG_READ_GAMMA_SUPPORTED
-   int gamma_shift;      /* number of "insignificant" bits in 16-bit gamma */
-   png_fixed_point gamma;        /* file gamma value */
-   png_fixed_point screen_gamma; /* screen gamma value (display_exponent) */
-
-   png_bytep gamma_table;     /* gamma table for 8-bit depth files */
-   png_uint_16pp gamma_16_table; /* gamma table for 16-bit depth files */
-#if defined(PNG_READ_BACKGROUND_SUPPORTED) || \
-   defined(PNG_READ_ALPHA_MODE_SUPPORTED) || \
-   defined(PNG_READ_RGB_TO_GRAY_SUPPORTED)
-   png_bytep gamma_from_1;    /* converts from 1.0 to screen */
-   png_bytep gamma_to_1;      /* converts from file to 1.0 */
-   png_uint_16pp gamma_16_from_1; /* converts from 1.0 to screen */
-   png_uint_16pp gamma_16_to_1; /* converts from file to 1.0 */
-#endif /* READ_BACKGROUND || READ_ALPHA_MODE || RGB_TO_GRAY */
-#endif
-
-#if defined(PNG_READ_GAMMA_SUPPORTED) || defined(PNG_sBIT_SUPPORTED)
-   png_color_8 sig_bit;       /* significant bits in each available channel */
-#endif
-
-#if defined(PNG_READ_SHIFT_SUPPORTED) || defined(PNG_WRITE_SHIFT_SUPPORTED)
-   png_color_8 shift;         /* shift for significant bit tranformation */
-#endif
-
-#if defined(PNG_tRNS_SUPPORTED) || defined(PNG_READ_BACKGROUND_SUPPORTED) \
- || defined(PNG_READ_EXPAND_SUPPORTED) || defined(PNG_READ_BACKGROUND_SUPPORTED)
-   png_bytep trans_alpha;           /* alpha values for paletted files */
-   png_color_16 trans_color;  /* transparent color for non-paletted files */
-#endif
-
-   png_read_status_ptr read_row_fn;   /* called after each row is decoded */
-   png_write_status_ptr write_row_fn; /* called after each row is encoded */
-#ifdef PNG_PROGRESSIVE_READ_SUPPORTED
-   png_progressive_info_ptr info_fn; /* called after header data fully read */
-   png_progressive_row_ptr row_fn;   /* called after a prog. row is decoded */
-   png_progressive_end_ptr end_fn;   /* called after image is complete */
-   png_bytep save_buffer_ptr;        /* current location in save_buffer */
-   png_bytep save_buffer;            /* buffer for previously read data */
-   png_bytep current_buffer_ptr;     /* current location in current_buffer */
-   png_bytep current_buffer;         /* buffer for recently used data */
-   png_uint_32 push_length;          /* size of current input chunk */
-   png_uint_32 skip_length;          /* bytes to skip in input data */
-   png_size_t save_buffer_size;      /* amount of data now in save_buffer */
-   png_size_t save_buffer_max;       /* total size of save_buffer */
-   png_size_t buffer_size;           /* total amount of available input data */
-   png_size_t current_buffer_size;   /* amount of data now in current_buffer */
-   int process_mode;                 /* what push library is currently doing */
-   int cur_palette;                  /* current push library palette index */
-
-#endif /* PNG_PROGRESSIVE_READ_SUPPORTED */
-
-#if defined(__TURBOC__) && !defined(_Windows) && !defined(__FLAT__)
-/* For the Borland special 64K segment handler */
-   png_bytepp offset_table_ptr;
-   png_bytep offset_table;
-   png_uint_16 offset_table_number;
-   png_uint_16 offset_table_count;
-   png_uint_16 offset_table_count_free;
-#endif
-
-#ifdef PNG_READ_QUANTIZE_SUPPORTED
-   png_bytep palette_lookup; /* lookup table for quantizing */
-   png_bytep quantize_index; /* index translation for palette files */
-#endif
-
-#if defined(PNG_READ_QUANTIZE_SUPPORTED) || defined(PNG_hIST_SUPPORTED)
-   png_uint_16p hist;                /* histogram */
-#endif
-
-#ifdef PNG_WRITE_WEIGHTED_FILTER_SUPPORTED
-   png_byte heuristic_method;        /* heuristic for row filter selection */
-   png_byte num_prev_filters;        /* number of weights for previous rows */
-   png_bytep prev_filters;           /* filter type(s) of previous row(s) */
-   png_uint_16p filter_weights;      /* weight(s) for previous line(s) */
-   png_uint_16p inv_filter_weights;  /* 1/weight(s) for previous line(s) */
-   png_uint_16p filter_costs;        /* relative filter calculation cost */
-   png_uint_16p inv_filter_costs;    /* 1/relative filter calculation cost */
-#endif
-
-#ifdef PNG_TIME_RFC1123_SUPPORTED
-   /* This is going to be unused in libpng16 and removed from libpng17 */
-   char time_buffer[29]; /* String to hold RFC 1123 time text */
-#endif
-
-/* New members added in libpng-1.0.6 */
-
-   png_uint_32 free_me;    /* flags items libpng is responsible for freeing */
-
-#ifdef PNG_USER_CHUNKS_SUPPORTED
-   png_voidp user_chunk_ptr;
-   png_user_chunk_ptr read_user_chunk_fn; /* user read chunk handler */
-#endif
-
-#ifdef PNG_HANDLE_AS_UNKNOWN_SUPPORTED
-   int num_chunk_list;
-   png_bytep chunk_list;
-#endif
-
-#ifdef PNG_READ_sRGB_SUPPORTED
-   /* Added in 1.5.5 to record an sRGB chunk in the png. */
-   png_byte is_sRGB;
-#endif
-
-/* New members added in libpng-1.0.3 */
-#ifdef PNG_READ_RGB_TO_GRAY_SUPPORTED
-   png_byte rgb_to_gray_status;
-   /* Added in libpng 1.5.5 to record setting of coefficients: */
-   png_byte rgb_to_gray_coefficients_set;
-   /* These were changed from png_byte in libpng-1.0.6 */
-   png_uint_16 rgb_to_gray_red_coeff;
-   png_uint_16 rgb_to_gray_green_coeff;
-   /* deleted in 1.5.5: rgb_to_gray_blue_coeff; */
-#endif
-
-/* New member added in libpng-1.0.4 (renamed in 1.0.9) */
-#if defined(PNG_MNG_FEATURES_SUPPORTED)
-/* Changed from png_byte to png_uint_32 at version 1.2.0 */
-   png_uint_32 mng_features_permitted;
-#endif
-
-/* New member added in libpng-1.0.9, ifdef'ed out in 1.0.12, enabled in 1.2.0 */
-#ifdef PNG_MNG_FEATURES_SUPPORTED
-   png_byte filter_type;
-#endif
-
-/* New members added in libpng-1.2.0 */
-
-/* New members added in libpng-1.0.2 but first enabled by default in 1.2.0 */
-#ifdef PNG_USER_MEM_SUPPORTED
-   png_voidp mem_ptr;             /* user supplied struct for mem functions */
-   png_malloc_ptr malloc_fn;      /* function for allocating memory */
-   png_free_ptr free_fn;          /* function for freeing memory */
-#endif
-
-/* New member added in libpng-1.0.13 and 1.2.0 */
-   png_bytep big_row_buf;         /* buffer to save current (unfiltered) row */
-
-#ifdef PNG_READ_QUANTIZE_SUPPORTED
-/* The following three members were added at version 1.0.14 and 1.2.4 */
-   png_bytep quantize_sort;          /* working sort array */
-   png_bytep index_to_palette;       /* where the original index currently is
-                                        in the palette */
-   png_bytep palette_to_index;       /* which original index points to this
-                                         palette color */
-#endif
-
-/* New members added in libpng-1.0.16 and 1.2.6 */
-   png_byte compression_type;
-
-#ifdef PNG_USER_LIMITS_SUPPORTED
-   png_uint_32 user_width_max;
-   png_uint_32 user_height_max;
-
-   /* Added in libpng-1.4.0: Total number of sPLT, text, and unknown
-    * chunks that can be stored (0 means unlimited).
-    */
-   png_uint_32 user_chunk_cache_max;
-
-   /* Total memory that a zTXt, sPLT, iTXt, iCCP, or unknown chunk
-    * can occupy when decompressed.  0 means unlimited.
-    */
-   png_alloc_size_t user_chunk_malloc_max;
-#endif
-
-/* New member added in libpng-1.0.25 and 1.2.17 */
-#ifdef PNG_UNKNOWN_CHUNKS_SUPPORTED
-   /* Storage for unknown chunk that the library doesn't recognize. */
-   png_unknown_chunk unknown_chunk;
-#endif
-
-/* New member added in libpng-1.2.26 */
-  png_size_t old_big_row_buf_size;
-
-/* New member added in libpng-1.2.30 */
-  png_charp chunkdata;  /* buffer for reading chunk data */
-
-#ifdef PNG_IO_STATE_SUPPORTED
-/* New member added in libpng-1.4.0 */
-   png_uint_32 io_state;
-#endif
-
-/* New member added in libpng-1.5.6 */
-   png_bytep big_prev_row;
-
-   void (*read_filter[PNG_FILTER_VALUE_LAST-1])(png_row_infop row_info,
-      png_bytep row, png_const_bytep prev_row);
-};
-#endif /* PNGSTRUCT_H */
diff --git a/plugingui/png/pngtrans.c b/plugingui/png/pngtrans.c
deleted file mode 100644
index 087d4bc..0000000
--- a/plugingui/png/pngtrans.c
+++ /dev/null
@@ -1,781 +0,0 @@
-
-/* pngtrans.c - transforms the data in a row (used by both readers and writers)
- *
- * Last changed in libpng 1.5.11 [June 14, 2012]
- * Copyright (c) 1998-2012 Glenn Randers-Pehrson
- * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
- * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)
- *
- * This code is released under the libpng license.
- * For conditions of distribution and use, see the disclaimer
- * and license in png.h
- */
-
-#include "pngpriv.h"
-
-#if defined(PNG_READ_SUPPORTED) || defined(PNG_WRITE_SUPPORTED)
-
-#if defined(PNG_READ_BGR_SUPPORTED) || defined(PNG_WRITE_BGR_SUPPORTED)
-/* Turn on BGR-to-RGB mapping */
-void PNGAPI
-png_set_bgr(png_structp png_ptr)
-{
-   png_debug(1, "in png_set_bgr");
-
-   if (png_ptr == NULL)
-      return;
-
-   png_ptr->transformations |= PNG_BGR;
-}
-#endif
-
-#if defined(PNG_READ_SWAP_SUPPORTED) || defined(PNG_WRITE_SWAP_SUPPORTED)
-/* Turn on 16 bit byte swapping */
-void PNGAPI
-png_set_swap(png_structp png_ptr)
-{
-   png_debug(1, "in png_set_swap");
-
-   if (png_ptr == NULL)
-      return;
-
-   if (png_ptr->bit_depth == 16)
-      png_ptr->transformations |= PNG_SWAP_BYTES;
-}
-#endif
-
-#if defined(PNG_READ_PACK_SUPPORTED) || defined(PNG_WRITE_PACK_SUPPORTED)
-/* Turn on pixel packing */
-void PNGAPI
-png_set_packing(png_structp png_ptr)
-{
-   png_debug(1, "in png_set_packing");
-
-   if (png_ptr == NULL)
-      return;
-
-   if (png_ptr->bit_depth < 8)
-   {
-      png_ptr->transformations |= PNG_PACK;
-      png_ptr->usr_bit_depth = 8;
-   }
-}
-#endif
-
-#if defined(PNG_READ_PACKSWAP_SUPPORTED)||defined(PNG_WRITE_PACKSWAP_SUPPORTED)
-/* Turn on packed pixel swapping */
-void PNGAPI
-png_set_packswap(png_structp png_ptr)
-{
-   png_debug(1, "in png_set_packswap");
-
-   if (png_ptr == NULL)
-      return;
-
-   if (png_ptr->bit_depth < 8)
-      png_ptr->transformations |= PNG_PACKSWAP;
-}
-#endif
-
-#if defined(PNG_READ_SHIFT_SUPPORTED) || defined(PNG_WRITE_SHIFT_SUPPORTED)
-void PNGAPI
-png_set_shift(png_structp png_ptr, png_const_color_8p true_bits)
-{
-   png_debug(1, "in png_set_shift");
-
-   if (png_ptr == NULL)
-      return;
-
-   png_ptr->transformations |= PNG_SHIFT;
-   png_ptr->shift = *true_bits;
-}
-#endif
-
-#if defined(PNG_READ_INTERLACING_SUPPORTED) || \
-    defined(PNG_WRITE_INTERLACING_SUPPORTED)
-int PNGAPI
-dg_png_set_interlace_handling(png_structp png_ptr)
-{
-   png_debug(1, "in png_set_interlace handling");
-
-   if (png_ptr && png_ptr->interlaced)
-   {
-      png_ptr->transformations |= PNG_INTERLACE;
-      return (7);
-   }
-
-   return (1);
-}
-#endif
-
-#if defined(PNG_READ_FILLER_SUPPORTED) || defined(PNG_WRITE_FILLER_SUPPORTED)
-/* Add a filler byte on read, or remove a filler or alpha byte on write.
- * The filler type has changed in v0.95 to allow future 2-byte fillers
- * for 48-bit input data, as well as to avoid problems with some compilers
- * that don't like bytes as parameters.
- */
-void PNGAPI
-png_set_filler(png_structp png_ptr, png_uint_32 filler, int filler_loc)
-{
-   png_debug(1, "in png_set_filler");
-
-   if (png_ptr == NULL)
-      return;
-
-   png_ptr->transformations |= PNG_FILLER;
-   png_ptr->filler = (png_uint_16)filler;
-
-   if (filler_loc == PNG_FILLER_AFTER)
-      png_ptr->flags |= PNG_FLAG_FILLER_AFTER;
-
-   else
-      png_ptr->flags &= ~PNG_FLAG_FILLER_AFTER;
-
-   /* This should probably go in the "do_read_filler" routine.
-    * I attempted to do that in libpng-1.0.1a but that caused problems
-    * so I restored it in libpng-1.0.2a
-   */
-
-   if (png_ptr->color_type == PNG_COLOR_TYPE_RGB)
-   {
-      png_ptr->usr_channels = 4;
-   }
-
-   /* Also I added this in libpng-1.0.2a (what happens when we expand
-    * a less-than-8-bit grayscale to GA?) */
-
-   if (png_ptr->color_type == PNG_COLOR_TYPE_GRAY && png_ptr->bit_depth >= 8)
-   {
-      png_ptr->usr_channels = 2;
-   }
-}
-
-/* Added to libpng-1.2.7 */
-void PNGAPI
-png_set_add_alpha(png_structp png_ptr, png_uint_32 filler, int filler_loc)
-{
-   png_debug(1, "in png_set_add_alpha");
-
-   if (png_ptr == NULL)
-      return;
-
-   png_set_filler(png_ptr, filler, filler_loc);
-   png_ptr->transformations |= PNG_ADD_ALPHA;
-}
-
-#endif
-
-#if defined(PNG_READ_SWAP_ALPHA_SUPPORTED) || \
-    defined(PNG_WRITE_SWAP_ALPHA_SUPPORTED)
-void PNGAPI
-png_set_swap_alpha(png_structp png_ptr)
-{
-   png_debug(1, "in png_set_swap_alpha");
-
-   if (png_ptr == NULL)
-      return;
-
-   png_ptr->transformations |= PNG_SWAP_ALPHA;
-}
-#endif
-
-#if defined(PNG_READ_INVERT_ALPHA_SUPPORTED) || \
-    defined(PNG_WRITE_INVERT_ALPHA_SUPPORTED)
-void PNGAPI
-png_set_invert_alpha(png_structp png_ptr)
-{
-   png_debug(1, "in png_set_invert_alpha");
-
-   if (png_ptr == NULL)
-      return;
-
-   png_ptr->transformations |= PNG_INVERT_ALPHA;
-}
-#endif
-
-#if defined(PNG_READ_INVERT_SUPPORTED) || defined(PNG_WRITE_INVERT_SUPPORTED)
-void PNGAPI
-png_set_invert_mono(png_structp png_ptr)
-{
-   png_debug(1, "in png_set_invert_mono");
-
-   if (png_ptr == NULL)
-      return;
-
-   png_ptr->transformations |= PNG_INVERT_MONO;
-}
-
-/* Invert monochrome grayscale data */
-void /* PRIVATE */
-png_do_invert(png_row_infop row_info, png_bytep row)
-{
-   png_debug(1, "in png_do_invert");
-
-  /* This test removed from libpng version 1.0.13 and 1.2.0:
-   *   if (row_info->bit_depth == 1 &&
-   */
-   if (row_info->color_type == PNG_COLOR_TYPE_GRAY)
-   {
-      png_bytep rp = row;
-      png_size_t i;
-      png_size_t istop = row_info->rowbytes;
-
-      for (i = 0; i < istop; i++)
-      {
-         *rp = (png_byte)(~(*rp));
-         rp++;
-      }
-   }
-
-   else if (row_info->color_type == PNG_COLOR_TYPE_GRAY_ALPHA &&
-      row_info->bit_depth == 8)
-   {
-      png_bytep rp = row;
-      png_size_t i;
-      png_size_t istop = row_info->rowbytes;
-
-      for (i = 0; i < istop; i += 2)
-      {
-         *rp = (png_byte)(~(*rp));
-         rp += 2;
-      }
-   }
-
-#ifdef PNG_16BIT_SUPPORTED
-   else if (row_info->color_type == PNG_COLOR_TYPE_GRAY_ALPHA &&
-      row_info->bit_depth == 16)
-   {
-      png_bytep rp = row;
-      png_size_t i;
-      png_size_t istop = row_info->rowbytes;
-
-      for (i = 0; i < istop; i += 4)
-      {
-         *rp = (png_byte)(~(*rp));
-         *(rp + 1) = (png_byte)(~(*(rp + 1)));
-         rp += 4;
-      }
-   }
-#endif
-}
-#endif
-
-#ifdef PNG_16BIT_SUPPORTED
-#if defined(PNG_READ_SWAP_SUPPORTED) || defined(PNG_WRITE_SWAP_SUPPORTED)
-/* Swaps byte order on 16 bit depth images */
-void /* PRIVATE */
-png_do_swap(png_row_infop row_info, png_bytep row)
-{
-   png_debug(1, "in png_do_swap");
-
-   if (row_info->bit_depth == 16)
-   {
-      png_bytep rp = row;
-      png_uint_32 i;
-      png_uint_32 istop= row_info->width * row_info->channels;
-
-      for (i = 0; i < istop; i++, rp += 2)
-      {
-         png_byte t = *rp;
-         *rp = *(rp + 1);
-         *(rp + 1) = t;
-      }
-   }
-}
-#endif
-#endif
-
-#if defined(PNG_READ_PACKSWAP_SUPPORTED)||defined(PNG_WRITE_PACKSWAP_SUPPORTED)
-static PNG_CONST png_byte onebppswaptable[256] = {
-   0x00, 0x80, 0x40, 0xC0, 0x20, 0xA0, 0x60, 0xE0,
-   0x10, 0x90, 0x50, 0xD0, 0x30, 0xB0, 0x70, 0xF0,
-   0x08, 0x88, 0x48, 0xC8, 0x28, 0xA8, 0x68, 0xE8,
-   0x18, 0x98, 0x58, 0xD8, 0x38, 0xB8, 0x78, 0xF8,
-   0x04, 0x84, 0x44, 0xC4, 0x24, 0xA4, 0x64, 0xE4,
-   0x14, 0x94, 0x54, 0xD4, 0x34, 0xB4, 0x74, 0xF4,
-   0x0C, 0x8C, 0x4C, 0xCC, 0x2C, 0xAC, 0x6C, 0xEC,
-   0x1C, 0x9C, 0x5C, 0xDC, 0x3C, 0xBC, 0x7C, 0xFC,
-   0x02, 0x82, 0x42, 0xC2, 0x22, 0xA2, 0x62, 0xE2,
-   0x12, 0x92, 0x52, 0xD2, 0x32, 0xB2, 0x72, 0xF2,
-   0x0A, 0x8A, 0x4A, 0xCA, 0x2A, 0xAA, 0x6A, 0xEA,
-   0x1A, 0x9A, 0x5A, 0xDA, 0x3A, 0xBA, 0x7A, 0xFA,
-   0x06, 0x86, 0x46, 0xC6, 0x26, 0xA6, 0x66, 0xE6,
-   0x16, 0x96, 0x56, 0xD6, 0x36, 0xB6, 0x76, 0xF6,
-   0x0E, 0x8E, 0x4E, 0xCE, 0x2E, 0xAE, 0x6E, 0xEE,
-   0x1E, 0x9E, 0x5E, 0xDE, 0x3E, 0xBE, 0x7E, 0xFE,
-   0x01, 0x81, 0x41, 0xC1, 0x21, 0xA1, 0x61, 0xE1,
-   0x11, 0x91, 0x51, 0xD1, 0x31, 0xB1, 0x71, 0xF1,
-   0x09, 0x89, 0x49, 0xC9, 0x29, 0xA9, 0x69, 0xE9,
-   0x19, 0x99, 0x59, 0xD9, 0x39, 0xB9, 0x79, 0xF9,
-   0x05, 0x85, 0x45, 0xC5, 0x25, 0xA5, 0x65, 0xE5,
-   0x15, 0x95, 0x55, 0xD5, 0x35, 0xB5, 0x75, 0xF5,
-   0x0D, 0x8D, 0x4D, 0xCD, 0x2D, 0xAD, 0x6D, 0xED,
-   0x1D, 0x9D, 0x5D, 0xDD, 0x3D, 0xBD, 0x7D, 0xFD,
-   0x03, 0x83, 0x43, 0xC3, 0x23, 0xA3, 0x63, 0xE3,
-   0x13, 0x93, 0x53, 0xD3, 0x33, 0xB3, 0x73, 0xF3,
-   0x0B, 0x8B, 0x4B, 0xCB, 0x2B, 0xAB, 0x6B, 0xEB,
-   0x1B, 0x9B, 0x5B, 0xDB, 0x3B, 0xBB, 0x7B, 0xFB,
-   0x07, 0x87, 0x47, 0xC7, 0x27, 0xA7, 0x67, 0xE7,
-   0x17, 0x97, 0x57, 0xD7, 0x37, 0xB7, 0x77, 0xF7,
-   0x0F, 0x8F, 0x4F, 0xCF, 0x2F, 0xAF, 0x6F, 0xEF,
-   0x1F, 0x9F, 0x5F, 0xDF, 0x3F, 0xBF, 0x7F, 0xFF
-};
-
-static PNG_CONST png_byte twobppswaptable[256] = {
-   0x00, 0x40, 0x80, 0xC0, 0x10, 0x50, 0x90, 0xD0,
-   0x20, 0x60, 0xA0, 0xE0, 0x30, 0x70, 0xB0, 0xF0,
-   0x04, 0x44, 0x84, 0xC4, 0x14, 0x54, 0x94, 0xD4,
-   0x24, 0x64, 0xA4, 0xE4, 0x34, 0x74, 0xB4, 0xF4,
-   0x08, 0x48, 0x88, 0xC8, 0x18, 0x58, 0x98, 0xD8,
-   0x28, 0x68, 0xA8, 0xE8, 0x38, 0x78, 0xB8, 0xF8,
-   0x0C, 0x4C, 0x8C, 0xCC, 0x1C, 0x5C, 0x9C, 0xDC,
-   0x2C, 0x6C, 0xAC, 0xEC, 0x3C, 0x7C, 0xBC, 0xFC,
-   0x01, 0x41, 0x81, 0xC1, 0x11, 0x51, 0x91, 0xD1,
-   0x21, 0x61, 0xA1, 0xE1, 0x31, 0x71, 0xB1, 0xF1,
-   0x05, 0x45, 0x85, 0xC5, 0x15, 0x55, 0x95, 0xD5,
-   0x25, 0x65, 0xA5, 0xE5, 0x35, 0x75, 0xB5, 0xF5,
-   0x09, 0x49, 0x89, 0xC9, 0x19, 0x59, 0x99, 0xD9,
-   0x29, 0x69, 0xA9, 0xE9, 0x39, 0x79, 0xB9, 0xF9,
-   0x0D, 0x4D, 0x8D, 0xCD, 0x1D, 0x5D, 0x9D, 0xDD,
-   0x2D, 0x6D, 0xAD, 0xED, 0x3D, 0x7D, 0xBD, 0xFD,
-   0x02, 0x42, 0x82, 0xC2, 0x12, 0x52, 0x92, 0xD2,
-   0x22, 0x62, 0xA2, 0xE2, 0x32, 0x72, 0xB2, 0xF2,
-   0x06, 0x46, 0x86, 0xC6, 0x16, 0x56, 0x96, 0xD6,
-   0x26, 0x66, 0xA6, 0xE6, 0x36, 0x76, 0xB6, 0xF6,
-   0x0A, 0x4A, 0x8A, 0xCA, 0x1A, 0x5A, 0x9A, 0xDA,
-   0x2A, 0x6A, 0xAA, 0xEA, 0x3A, 0x7A, 0xBA, 0xFA,
-   0x0E, 0x4E, 0x8E, 0xCE, 0x1E, 0x5E, 0x9E, 0xDE,
-   0x2E, 0x6E, 0xAE, 0xEE, 0x3E, 0x7E, 0xBE, 0xFE,
-   0x03, 0x43, 0x83, 0xC3, 0x13, 0x53, 0x93, 0xD3,
-   0x23, 0x63, 0xA3, 0xE3, 0x33, 0x73, 0xB3, 0xF3,
-   0x07, 0x47, 0x87, 0xC7, 0x17, 0x57, 0x97, 0xD7,
-   0x27, 0x67, 0xA7, 0xE7, 0x37, 0x77, 0xB7, 0xF7,
-   0x0B, 0x4B, 0x8B, 0xCB, 0x1B, 0x5B, 0x9B, 0xDB,
-   0x2B, 0x6B, 0xAB, 0xEB, 0x3B, 0x7B, 0xBB, 0xFB,
-   0x0F, 0x4F, 0x8F, 0xCF, 0x1F, 0x5F, 0x9F, 0xDF,
-   0x2F, 0x6F, 0xAF, 0xEF, 0x3F, 0x7F, 0xBF, 0xFF
-};
-
-static PNG_CONST png_byte fourbppswaptable[256] = {
-   0x00, 0x10, 0x20, 0x30, 0x40, 0x50, 0x60, 0x70,
-   0x80, 0x90, 0xA0, 0xB0, 0xC0, 0xD0, 0xE0, 0xF0,
-   0x01, 0x11, 0x21, 0x31, 0x41, 0x51, 0x61, 0x71,
-   0x81, 0x91, 0xA1, 0xB1, 0xC1, 0xD1, 0xE1, 0xF1,
-   0x02, 0x12, 0x22, 0x32, 0x42, 0x52, 0x62, 0x72,
-   0x82, 0x92, 0xA2, 0xB2, 0xC2, 0xD2, 0xE2, 0xF2,
-   0x03, 0x13, 0x23, 0x33, 0x43, 0x53, 0x63, 0x73,
-   0x83, 0x93, 0xA3, 0xB3, 0xC3, 0xD3, 0xE3, 0xF3,
-   0x04, 0x14, 0x24, 0x34, 0x44, 0x54, 0x64, 0x74,
-   0x84, 0x94, 0xA4, 0xB4, 0xC4, 0xD4, 0xE4, 0xF4,
-   0x05, 0x15, 0x25, 0x35, 0x45, 0x55, 0x65, 0x75,
-   0x85, 0x95, 0xA5, 0xB5, 0xC5, 0xD5, 0xE5, 0xF5,
-   0x06, 0x16, 0x26, 0x36, 0x46, 0x56, 0x66, 0x76,
-   0x86, 0x96, 0xA6, 0xB6, 0xC6, 0xD6, 0xE6, 0xF6,
-   0x07, 0x17, 0x27, 0x37, 0x47, 0x57, 0x67, 0x77,
-   0x87, 0x97, 0xA7, 0xB7, 0xC7, 0xD7, 0xE7, 0xF7,
-   0x08, 0x18, 0x28, 0x38, 0x48, 0x58, 0x68, 0x78,
-   0x88, 0x98, 0xA8, 0xB8, 0xC8, 0xD8, 0xE8, 0xF8,
-   0x09, 0x19, 0x29, 0x39, 0x49, 0x59, 0x69, 0x79,
-   0x89, 0x99, 0xA9, 0xB9, 0xC9, 0xD9, 0xE9, 0xF9,
-   0x0A, 0x1A, 0x2A, 0x3A, 0x4A, 0x5A, 0x6A, 0x7A,
-   0x8A, 0x9A, 0xAA, 0xBA, 0xCA, 0xDA, 0xEA, 0xFA,
-   0x0B, 0x1B, 0x2B, 0x3B, 0x4B, 0x5B, 0x6B, 0x7B,
-   0x8B, 0x9B, 0xAB, 0xBB, 0xCB, 0xDB, 0xEB, 0xFB,
-   0x0C, 0x1C, 0x2C, 0x3C, 0x4C, 0x5C, 0x6C, 0x7C,
-   0x8C, 0x9C, 0xAC, 0xBC, 0xCC, 0xDC, 0xEC, 0xFC,
-   0x0D, 0x1D, 0x2D, 0x3D, 0x4D, 0x5D, 0x6D, 0x7D,
-   0x8D, 0x9D, 0xAD, 0xBD, 0xCD, 0xDD, 0xED, 0xFD,
-   0x0E, 0x1E, 0x2E, 0x3E, 0x4E, 0x5E, 0x6E, 0x7E,
-   0x8E, 0x9E, 0xAE, 0xBE, 0xCE, 0xDE, 0xEE, 0xFE,
-   0x0F, 0x1F, 0x2F, 0x3F, 0x4F, 0x5F, 0x6F, 0x7F,
-   0x8F, 0x9F, 0xAF, 0xBF, 0xCF, 0xDF, 0xEF, 0xFF
-};
-
-/* Swaps pixel packing order within bytes */
-void /* PRIVATE */
-png_do_packswap(png_row_infop row_info, png_bytep row)
-{
-   png_debug(1, "in png_do_packswap");
-
-   if (row_info->bit_depth < 8)
-   {
-      png_bytep rp;
-      png_const_bytep end, table;
-
-      end = row + row_info->rowbytes;
-
-      if (row_info->bit_depth == 1)
-         table = onebppswaptable;
-
-      else if (row_info->bit_depth == 2)
-         table = twobppswaptable;
-
-      else if (row_info->bit_depth == 4)
-         table = fourbppswaptable;
-
-      else
-         return;
-
-      for (rp = row; rp < end; rp++)
-         *rp = table[*rp];
-   }
-}
-#endif /* PNG_READ_PACKSWAP_SUPPORTED or PNG_WRITE_PACKSWAP_SUPPORTED */
-
-#if defined(PNG_WRITE_FILLER_SUPPORTED) || \
-    defined(PNG_READ_STRIP_ALPHA_SUPPORTED)
-/* Remove a channel - this used to be 'png_do_strip_filler' but it used a
- * somewhat weird combination of flags to determine what to do.  All the calls
- * to png_do_strip_filler are changed in 1.5.2 to call this instead with the
- * correct arguments.
- *
- * The routine isn't general - the channel must be the channel at the start or
- * end (not in the middle) of each pixel.
- */
-void /* PRIVATE */
-png_do_strip_channel(png_row_infop row_info, png_bytep row, int at_start)
-{
-   png_bytep sp = row; /* source pointer */
-   png_bytep dp = row; /* destination pointer */
-   png_bytep ep = row + row_info->rowbytes; /* One beyond end of row */
-
-   /* At the start sp will point to the first byte to copy and dp to where
-    * it is copied to.  ep always points just beyond the end of the row, so
-    * the loop simply copies (channels-1) channels until sp reaches ep.
-    *
-    * at_start:        0 -- convert AG, XG, ARGB, XRGB, AAGG, XXGG, etc.
-    *            nonzero -- convert GA, GX, RGBA, RGBX, GGAA, RRGGBBXX, etc.
-    */
-
-   /* GA, GX, XG cases */
-   if (row_info->channels == 2)
-   {
-      if (row_info->bit_depth == 8)
-      {
-         if (at_start) /* Skip initial filler */
-            ++sp;
-         else          /* Skip initial channel and, for sp, the filler */
-            sp += 2, ++dp;
-
-         /* For a 1 pixel wide image there is nothing to do */
-         while (sp < ep)
-            *dp++ = *sp, sp += 2;
-
-         row_info->pixel_depth = 8;
-      }
-
-      else if (row_info->bit_depth == 16)
-      {
-         if (at_start) /* Skip initial filler */
-            sp += 2;
-         else          /* Skip initial channel and, for sp, the filler */
-            sp += 4, dp += 2;
-
-         while (sp < ep)
-            *dp++ = *sp++, *dp++ = *sp, sp += 3;
-
-         row_info->pixel_depth = 16;
-      }
-
-      else
-         return; /* bad bit depth */
-
-      row_info->channels = 1;
-
-      /* Finally fix the color type if it records an alpha channel */
-      if (row_info->color_type == PNG_COLOR_TYPE_GRAY_ALPHA)
-         row_info->color_type = PNG_COLOR_TYPE_GRAY;
-   }
-
-   /* RGBA, RGBX, XRGB cases */
-   else if (row_info->channels == 4)
-   {
-      if (row_info->bit_depth == 8)
-      {
-         if (at_start) /* Skip initial filler */
-            ++sp;
-         else          /* Skip initial channels and, for sp, the filler */
-            sp += 4, dp += 3;
-
-         /* Note that the loop adds 3 to dp and 4 to sp each time. */
-         while (sp < ep)
-            *dp++ = *sp++, *dp++ = *sp++, *dp++ = *sp, sp += 2;
-
-         row_info->pixel_depth = 24;
-      }
-
-      else if (row_info->bit_depth == 16)
-      {
-         if (at_start) /* Skip initial filler */
-            sp += 2;
-         else          /* Skip initial channels and, for sp, the filler */
-            sp += 8, dp += 6;
-
-         while (sp < ep)
-         {
-            /* Copy 6 bytes, skip 2 */
-            *dp++ = *sp++, *dp++ = *sp++;
-            *dp++ = *sp++, *dp++ = *sp++;
-            *dp++ = *sp++, *dp++ = *sp, sp += 3;
-         }
-
-         row_info->pixel_depth = 48;
-      }
-
-      else
-         return; /* bad bit depth */
-
-      row_info->channels = 3;
-
-      /* Finally fix the color type if it records an alpha channel */
-      if (row_info->color_type == PNG_COLOR_TYPE_RGB_ALPHA)
-         row_info->color_type = PNG_COLOR_TYPE_RGB;
-   }
-
-   else
-      return; /* The filler channel has gone already */
-
-   /* Fix the rowbytes value. */
-   row_info->rowbytes = dp-row;
-}
-#endif
-
-#if defined(PNG_READ_BGR_SUPPORTED) || defined(PNG_WRITE_BGR_SUPPORTED)
-/* Swaps red and blue bytes within a pixel */
-void /* PRIVATE */
-png_do_bgr(png_row_infop row_info, png_bytep row)
-{
-   png_debug(1, "in png_do_bgr");
-
-   if ((row_info->color_type & PNG_COLOR_MASK_COLOR))
-   {
-      png_uint_32 row_width = row_info->width;
-      if (row_info->bit_depth == 8)
-      {
-         if (row_info->color_type == PNG_COLOR_TYPE_RGB)
-         {
-            png_bytep rp;
-            png_uint_32 i;
-
-            for (i = 0, rp = row; i < row_width; i++, rp += 3)
-            {
-               png_byte save = *rp;
-               *rp = *(rp + 2);
-               *(rp + 2) = save;
-            }
-         }
-
-         else if (row_info->color_type == PNG_COLOR_TYPE_RGB_ALPHA)
-         {
-            png_bytep rp;
-            png_uint_32 i;
-
-            for (i = 0, rp = row; i < row_width; i++, rp += 4)
-            {
-               png_byte save = *rp;
-               *rp = *(rp + 2);
-               *(rp + 2) = save;
-            }
-         }
-      }
-
-#ifdef PNG_16BIT_SUPPORTED
-      else if (row_info->bit_depth == 16)
-      {
-         if (row_info->color_type == PNG_COLOR_TYPE_RGB)
-         {
-            png_bytep rp;
-            png_uint_32 i;
-
-            for (i = 0, rp = row; i < row_width; i++, rp += 6)
-            {
-               png_byte save = *rp;
-               *rp = *(rp + 4);
-               *(rp + 4) = save;
-               save = *(rp + 1);
-               *(rp + 1) = *(rp + 5);
-               *(rp + 5) = save;
-            }
-         }
-
-         else if (row_info->color_type == PNG_COLOR_TYPE_RGB_ALPHA)
-         {
-            png_bytep rp;
-            png_uint_32 i;
-
-            for (i = 0, rp = row; i < row_width; i++, rp += 8)
-            {
-               png_byte save = *rp;
-               *rp = *(rp + 4);
-               *(rp + 4) = save;
-               save = *(rp + 1);
-               *(rp + 1) = *(rp + 5);
-               *(rp + 5) = save;
-            }
-         }
-      }
-#endif
-   }
-}
-#endif /* PNG_READ_BGR_SUPPORTED or PNG_WRITE_BGR_SUPPORTED */
-
-#if defined(PNG_READ_CHECK_FOR_INVALID_INDEX_SUPPORTED) || \
-    defined(PNG_WRITE_CHECK_FOR_INVALID_INDEX_SUPPORTED)
-/* Added at libpng-1.5.10 */
-void /* PRIVATE */
-png_do_check_palette_indexes(png_structp png_ptr, png_row_infop row_info)
-{
-   if (png_ptr->num_palette < (1 << row_info->bit_depth) &&
-      png_ptr->num_palette > 0) /* num_palette can be 0 in MNG files */
-   {
-      /* Calculations moved outside switch in an attempt to stop different
-       * compiler warnings.  'padding' is in *bits* within the last byte, it is
-       * an 'int' because pixel_depth becomes an 'int' in the expression below,
-       * and this calculation is used because it avoids warnings that other
-       * forms produced on either GCC or MSVC.
-       */
-      int padding = (-row_info->pixel_depth * row_info->width) & 7;
-      png_bytep rp = png_ptr->row_buf + row_info->rowbytes;
-
-      switch (row_info->bit_depth)
-      {
-         case 1:
-         {
-            /* in this case, all bytes must be 0 so we don't need
-             * to unpack the pixels except for the rightmost one.
-             */
-            for (; rp > png_ptr->row_buf; rp--)
-            {
-              if (*rp >> padding != 0)
-                 png_ptr->num_palette_max = 1;
-              padding = 0;
-            }
-
-            break;
-         }
-
-         case 2:
-         {
-            for (; rp > png_ptr->row_buf; rp--)
-            {
-              int i = ((*rp >> padding) & 0x03);
-
-              if (i > png_ptr->num_palette_max)
-                 png_ptr->num_palette_max = i;
-
-              i = (((*rp >> padding) >> 2) & 0x03);
-
-              if (i > png_ptr->num_palette_max)
-                 png_ptr->num_palette_max = i;
-
-              i = (((*rp >> padding) >> 4) & 0x03);
-
-              if (i > png_ptr->num_palette_max)
-                 png_ptr->num_palette_max = i;
-
-              i = (((*rp >> padding) >> 6) & 0x03);
-
-              if (i > png_ptr->num_palette_max)
-                 png_ptr->num_palette_max = i;
-
-              padding = 0;
-            }
-
-            break;
-         }
-
-         case 4:
-         {
-            for (; rp > png_ptr->row_buf; rp--)
-            {
-              int i = ((*rp >> padding) & 0x0f);
-
-              if (i > png_ptr->num_palette_max)
-                 png_ptr->num_palette_max = i;
-
-              i = (((*rp >> padding) >> 4) & 0x0f);
-
-              if (i > png_ptr->num_palette_max)
-                 png_ptr->num_palette_max = i;
-
-              padding = 0;
-            }
-
-            break;
-         }
-
-         case 8:
-         {
-            for (; rp > png_ptr->row_buf; rp--)
-            {
-               if (*rp > png_ptr->num_palette_max)
-                  png_ptr->num_palette_max = (int) *rp;
-            }
-
-            break;
-         }
-
-         default:
-            break;
-      }
-   }
-}
-#endif /* PNG_CHECK_FOR_INVALID_INDEX_SUPPORTED */
-
-#if defined(PNG_READ_USER_TRANSFORM_SUPPORTED) || \
-    defined(PNG_WRITE_USER_TRANSFORM_SUPPORTED)
-#ifdef PNG_USER_TRANSFORM_PTR_SUPPORTED
-void PNGAPI
-png_set_user_transform_info(png_structp png_ptr, png_voidp
-   user_transform_ptr, int user_transform_depth, int user_transform_channels)
-{
-   png_debug(1, "in png_set_user_transform_info");
-
-   if (png_ptr == NULL)
-      return;
-   png_ptr->user_transform_ptr = user_transform_ptr;
-   png_ptr->user_transform_depth = (png_byte)user_transform_depth;
-   png_ptr->user_transform_channels = (png_byte)user_transform_channels;
-}
-#endif
-
-/* This function returns a pointer to the user_transform_ptr associated with
- * the user transform functions.  The application should free any memory
- * associated with this pointer before png_write_destroy and png_read_destroy
- * are called.
- */
-#ifdef PNG_USER_TRANSFORM_PTR_SUPPORTED
-png_voidp PNGAPI
-png_get_user_transform_ptr(png_const_structp png_ptr)
-{
-   if (png_ptr == NULL)
-      return (NULL);
-
-   return ((png_voidp)png_ptr->user_transform_ptr);
-}
-#endif
-
-#ifdef PNG_USER_TRANSFORM_INFO_SUPPORTED
-png_uint_32 PNGAPI
-png_get_current_row_number(png_const_structp png_ptr)
-{
-   /* See the comments in png.h - this is the sub-image row when reading and
-    * interlaced image.
-    */
-   if (png_ptr != NULL)
-      return png_ptr->row_number;
-
-   return PNG_UINT_32_MAX; /* help the app not to fail silently */
-}
-
-png_byte PNGAPI
-png_get_current_pass_number(png_const_structp png_ptr)
-{
-   if (png_ptr != NULL)
-      return png_ptr->pass;
-   return 8; /* invalid */
-}
-#endif /* PNG_USER_TRANSFORM_INFO_SUPPORTED */
-#endif /* PNG_READ_USER_TRANSFORM_SUPPORTED ||
-          PNG_WRITE_USER_TRANSFORM_SUPPORTED */
-#endif /* PNG_READ_SUPPORTED || PNG_WRITE_SUPPORTED */
diff --git a/vst/Makefile.mingw32 b/vst/Makefile.mingw32
index 9a9707a..ea7b1e0 100644
--- a/vst/Makefile.mingw32
+++ b/vst/Makefile.mingw32
@@ -68,17 +68,7 @@ GUI_SRC = \
 	$(top_srcdir)/plugingui/progressbar.cc \
 	$(top_srcdir)/plugingui/verticalline.cc \
 	$(top_srcdir)/plugingui/resource.cc \
-	$(top_srcdir)/plugingui/resource_data.cc \
-	$(top_srcdir)/plugingui/png/png.c \
-	$(top_srcdir)/plugingui/png/pngerror.c \
-	$(top_srcdir)/plugingui/png/pngmem.c \
-	$(top_srcdir)/plugingui/png/pngread.c \
-	$(top_srcdir)/plugingui/png/pngget.c \
-	$(top_srcdir)/plugingui/png/pngtrans.c \
-	$(top_srcdir)/plugingui/png/pngrutil.c \
-	$(top_srcdir)/plugingui/png/pngset.c \
-	$(top_srcdir)/plugingui/png/pngrio.c \
-	$(top_srcdir)/plugingui/png/pngrtran.c
+	$(top_srcdir)/plugingui/resource_data.cc
 
 GUI_CFLAGS=-I../plugingui -DUSE_THREAD
 GUI_LIBS=-lgdi32 -lsetupapi -lws2_32
@@ -108,10 +98,6 @@ PNG_BASE=${MSYS}
 PNG_CFLAGS=-I${PNG_BASE}/include
 PNG_LIBS=-L${PNG_BASE}/lib -lz
 
-ZLIB_BASE=/c/zlib-1.2.7
-ZLIB_CFLAGS=-I${ZLIB_BASE}
-ZLIB_LIBS=-L${ZLIB_BASE} -lz
-
 SRC = \
 	drumgizmo_vst.cc \
 	input_vst.cc \
@@ -151,7 +137,7 @@ SRC = \
 all:
 	gcc $(DBG_CFLAGS) $(top_srcdir)/hugin/hugin.c -c
 	gcc $(DBG_CFLAGS) $(top_srcdir)/hugin/hugin_syslog.c -c
-	g++ -static -static-libgcc -O2 -g -Wall -DWIN32 $(DBG_CFLAGS) $(ZLIB_CFLAGS) $(DG_CFLAGS) $(DG_LIBS) $(VST_CFLAGS) hugin.o hugin_syslog.o $(DG_SRC) $(VST_SRC) ${SRC} ${GUI_SRC} ${GUI_CFLAGS} $(GUI_LIBS) $(EXPAT_CFLAGS) $(EXPAT_LIBS) $(SNDFILE_CFLAGS) $(SNDFILE_LIBS) $(ZLIB_LIBS) -shared -o drumgizmo_vst.dll -Wl,--out-implib,libdrumgizmo_vst.a
+	g++ -static -static-libgcc -O2 -g -Wall -DWIN32 $(DBG_CFLAGS) $(DG_CFLAGS) $(DG_LIBS) $(VST_CFLAGS) hugin.o hugin_syslog.o $(DG_SRC) $(VST_SRC) ${SRC} ${GUI_SRC} ${GUI_CFLAGS} $(GUI_LIBS) $(EXPAT_CFLAGS) $(EXPAT_LIBS) $(SNDFILE_CFLAGS) $(SNDFILE_LIBS) -shared -o drumgizmo_vst.dll -Wl,--out-implib,libdrumgizmo_vst.a
  
 clean:
 	del -f drumgizmo_vst.dll libdrumgizmo_vst.a