New experimental sample selector (enable using --with-experimental argument on ./configure).

1 files changed, 219 insertions, 0 deletions

diff --git a/src/powerlist.cc b/src/powerlist.cc
new file mode 100644
index 0000000..a298927
--- /dev/null
+++ b/src/powerlist.cc
@@ -0,0 +1,219 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/***************************************************************************
+ *            powerlist.cc
+ *
+ *  Sun Jul 28 19:45:48 CEST 2013
+ *  Copyright 2013 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 "powerlist.h"
+
+#include <stdlib.h>
+#include <math.h>
+#include <string.h>
+
+#include <hugin.hpp>
+
+#define SIZE 500
+
+// Box–Muller transform.
+// See: http://en.wikipedia.org/wiki/Box%E2%80%93Muller_transform
+float box_muller_transform(float mean, float stddev)
+{
+  float U1 = (float)rand() / (float)RAND_MAX;
+  float U2 = (float)rand() / (float)RAND_MAX;
+
+  float x = sqrt(-2.0 * log(U1)) * cos(2.0 * M_PI * U2);
+
+  return mean + stddev * x;
+}
+
+PowerList::PowerList()
+{
+  power_max = 0;
+}
+
+#define THRES 1.0
+
+void PowerList::add(Sample *sample)
+{
+  PowerListItem item;
+  item.power = -1;
+  item.sample = sample;
+
+  samples.push_back(item);
+}
+
+Channel *PowerList::getMasterChannel()
+{
+  std::map<Channel *, int> count;
+
+  std::vector<PowerListItem>::iterator si = samples.begin();
+  while(si != samples.end()) {
+    PowerListItem &item = *si;
+    Sample *sample = item.sample;
+
+    Channel *max_channel = NULL;
+    sample_t max_val = 0;
+
+    // DEBUG(rand, "Sample: %s\n", sample->name.c_str());
+
+    size_t ci = 0;
+    AudioFiles::iterator ai = sample->audiofiles.begin();
+    while(ai != sample->audiofiles.end()) {
+      Channel *c = ai->first;
+      AudioFile *af = ai->second;
+
+      af->load(SIZE);
+
+      float silence = 0;
+      size_t silence_length = 4;
+      for(size_t s = af->size; s > 0 && s > af->size - silence_length; s--) {
+        silence += af->data[s];
+      }
+      silence /= silence_length;
+
+      size_t s = 0;
+      for(; s < af->size; s++) {
+        float val = af->data[s] * af->data[s] * (1.0 / (float)(s+1));
+        if(val > max_val) {
+          max_val = val;
+          max_channel = c;
+          break;
+        }
+      }
+      
+      af->unload();
+
+      ai++;
+      ci++;
+    }
+
+    if(max_channel) {
+      if(count.find(max_channel) == count.end()) count[max_channel] = 0;
+      count[max_channel]++;
+    }
+
+    si++;
+  }
+
+  Channel *master = NULL;
+  int max_count = -1;
+
+  std::map<Channel *, int>::iterator ci = count.begin();
+  while(ci != count.end()) {
+    if(ci->second > max_count &&
+       strstr(ci->first->name.c_str(), "Alesis") == 0) {
+      master = ci->first;
+      max_count = ci->second;
+    }
+    ci++;
+  }
+
+  return master;
+}
+
+void PowerList::finalise()
+{
+  Channel *master_channel = getMasterChannel();
+
+  if(master_channel == NULL) {
+    ERR(rand, "No master channel found!\n");
+    return; // This should not happen...
+  }
+
+  DEBUG(rand, "Master channel: %s\n", master_channel->name.c_str());
+
+  std::vector<PowerListItem>::iterator si = samples.begin();
+  while(si != samples.end()) {
+    PowerListItem &item = *si;
+    Sample *sample = item.sample;
+
+    DEBUG(rand, "Sample: %s\n", sample->name.c_str());
+
+    AudioFile *master = NULL;
+
+    AudioFiles::iterator afi = sample->audiofiles.begin();
+    while(afi != sample->audiofiles.end()) {
+      if(afi->first->name == master_channel->name) {
+        master = afi->second;
+        break;
+      }
+      afi++;
+    }
+
+    if(master == NULL) {
+      si++;
+      continue;
+    }
+
+    master->load();
+
+    float power = 0;
+    size_t s = 0;
+    for(; s < SIZE && s < master->size; s++) {
+      power += master->data[s] * master->data[s];
+    }
+    
+    power = sqrt(power);
+
+    if(power > power_max) power_max = power;
+
+    item.power = power;
+
+    DEBUG(rand, " - power: %f\n", power);
+    
+    si++;
+  }
+}
+
+Sample *PowerList::get(level_t level)
+{
+  Sample *sample = NULL;
+  float power = 0;
+
+  float mean = level * power_max;
+  float stddev = power_max / samples.size() * 2;
+
+  float lvl = box_muller_transform(mean, stddev);
+
+  DEBUG(rand, "lvl: %f (mean: %.2f, stddev: %.2f)\n",
+        lvl, mean, stddev);
+
+  std::vector<PowerListItem>::iterator i = samples.begin();
+  while(i != samples.end()) {
+    if(sample == NULL) {
+      sample = i->sample;
+      power = i->power;
+    }
+
+    if(fabs(i->power - lvl) < fabs(power - lvl)) {
+      sample = i->sample;
+      power = i->power;
+    }
+
+    i++;
+  }
+
+  DEBUG(rand, "Found power %f\n", power);
+
+  return sample;
+}