Add new resampler class and use it in engine.

1 files changed, 170 insertions, 0 deletions

diff --git a/src/chresampler.cc b/src/chresampler.cc
new file mode 100644
index 0000000..301e650
--- /dev/null
+++ b/src/chresampler.cc
@@ -0,0 +1,170 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/***************************************************************************
+ *            chresampler.cc
+ *
+ *  Tue Sep 23 20:42:14 CEST 2014
+ *  Copyright 2014 Bent Bisballe Nyeng
+ *  deva@aasimon.org
+ ****************************************************************************/
+
+/*
+ *  This file is part of DrumGizmo.
+ *
+ *  DrumGizmo is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation; either version 2 of the License, or
+ *  (at your option) any later version.
+ *
+ *  DrumGizmo is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with DrumGizmo; if not, write to the Free Software
+ *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA.
+ */
+#include "chresampler.h"
+
+#include <config.h>
+#include <hugin.hpp>
+#include <stdio.h>
+
+#ifdef WITH_RESAMPLER
+
+#if defined(USE_ZITA)
+  #include <zita-resampler/resampler.h>
+#elif defined(USE_SRC)
+  #include <samplerate.h>
+#else
+  #error "No resampler selected"
+#endif
+
+class CHResampler::Prv {
+public:
+#if defined(USE_ZITA)
+  Resampler zita;
+#elif defined(USE_SRC)
+  SRC_STATE *state;
+  SRC_DATA data;
+#endif
+};
+
+CHResampler::CHResampler()
+{
+  input_fs = 44100;
+  output_fs = 44100;
+
+  prv = new Prv();
+#if defined(SRC)
+  prv->state = NULL;
+#endif
+}
+
+void CHResampler::setup(double input_fs, double output_fs)
+{
+  int nchan = 1; // always mono
+
+  this->input_fs = input_fs;
+  this->output_fs = output_fs;
+
+#if defined(USE_ZITA)
+  DEBUG(resampler, "Using zita-resampler (%d -> %d)", (int)input_fs, (int)output_fs);
+
+  int hlen = 72; // 16 ≤ hlen ≤ 96
+  // delay is 2 * hlen, 72 corresponds to delay introduced by SRC.
+  prv->zita.setup(input_fs, output_fs, nchan, hlen);
+#elif defined(USE_SRC)
+  DEBUG(resampler, "Using libsamplerate (%d -> %d)", (int)input_fs, (int)output_fs);
+
+  int err;
+  prv->state = src_new(SRC_SINC_BEST_QUALITY, nchan, &err);
+  (void)err;
+  //  printf("err: %d\n", err);
+  src_set_ratio(prv->state, output_fs / input_fs);
+  prv->data.src_ratio = output_fs / input_fs;
+  prv->data.end_of_input = 0;
+#endif
+}
+
+CHResampler::~CHResampler()
+{
+#if defined(USE_ZITA)
+#elif defined(USE_SRC)
+  if(prv->state) src_delete(prv->state);
+#endif
+  delete prv;
+}
+
+void CHResampler::setInputSamples(float *samples, size_t count)
+{
+#if defined(USE_ZITA)
+  prv->zita.inp_data = samples;
+  prv->zita.inp_count = count;
+#elif defined(USE_SRC)
+  prv->data.data_in = samples;
+  prv->data.input_frames = count;
+#endif
+}
+
+void CHResampler::setOutputSamples(float *samples, size_t count)
+{
+#if defined(USE_ZITA)
+  prv->zita.out_data = samples;
+  prv->zita.out_count = count;
+#elif defined(USE_SRC)
+  prv->data.data_out = samples;
+  prv->data.output_frames = count;
+#endif
+}
+
+void CHResampler::process()
+{
+#if defined(USE_ZITA)
+  prv->zita.process();
+#elif defined(USE_SRC)
+  src_process(prv->state, &prv->data);
+  prv->data.output_frames -= prv->data.output_frames_gen;
+  prv->data.data_out +=  prv->data.output_frames_gen;
+  prv->data.input_frames -= prv->data.input_frames_used;
+  prv->data.data_in += prv->data.input_frames_used;
+#endif
+}
+
+size_t CHResampler::getInputSampleCount()
+{
+#if defined(USE_ZITA)
+  return prv->zita.inp_count;
+#elif defined(USE_SRC)
+  return prv->data.input_frames;
+#endif
+}
+
+size_t CHResampler::getOutputSampleCount()
+{
+#if defined(USE_ZITA)
+  return prv->zita.out_count;
+#elif defined(USE_SRC)
+  return prv->data.output_frames;
+#endif
+}
+
+double CHResampler::ratio()
+{
+  return input_fs / output_fs;
+}
+
+#else
+
+// Dummy implementation
+CHResampler::CHResampler() {}
+CHResampler::~CHResampler() {}
+void CHResampler::setup(double, double) {}
+void CHResampler::setInputSamples(float *, size_t) {}
+void CHResampler::setOutputSamples(float *, size_t) {}
+void CHResampler::process() {}
+size_t CHResampler::getInputSampleCount() { return 0; }
+size_t CHResampler::getOutputSampleCount() { return 0; }
+double CHResampler::ratio() { return 1; }
+
+#endif/*WITH_RESAMPLER*/