diff audio/ClipMixer.cpp @ 468:56acd9368532 bqaudioio

Initial work toward switching to bqaudioio library (so as to get I/O, not just O)

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/audio/ClipMixer.cpp	Tue Aug 04 13:27:42 2015 +0100
@@ -0,0 +1,248 @@
+/* -*- c-basic-offset: 4 indent-tabs-mode: nil -*-  vi:set ts=8 sts=4 sw=4: */
+
+/*
+    Sonic Visualiser
+    An audio file viewer and annotation editor.
+    Centre for Digital Music, Queen Mary, University of London.
+    This file copyright 2006 Chris Cannam, 2006-2014 QMUL.
+    
+    This program 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.  See the file
+    COPYING included with this distribution for more information.
+*/
+
+#include "ClipMixer.h"
+
+#include <sndfile.h>
+#include <cmath>
+
+#include "base/Debug.h"
+
+//#define DEBUG_CLIP_MIXER 1
+
+ClipMixer::ClipMixer(int channels, sv_samplerate_t sampleRate, sv_frame_t blockSize) :
+    m_channels(channels),
+    m_sampleRate(sampleRate),
+    m_blockSize(blockSize),
+    m_clipData(0),
+    m_clipLength(0),
+    m_clipF0(0),
+    m_clipRate(0)
+{
+}
+
+ClipMixer::~ClipMixer()
+{
+    if (m_clipData) free(m_clipData);
+}
+
+void
+ClipMixer::setChannelCount(int channels)
+{
+    m_channels = channels;
+}
+
+bool
+ClipMixer::loadClipData(QString path, double f0, double level)
+{
+    if (m_clipData) {
+        cerr << "ClipMixer::loadClipData: Already have clip loaded" << endl;
+        return false;
+    }
+
+    SF_INFO info;
+    SNDFILE *file;
+    float *tmpFrames;
+    sv_frame_t i;
+
+    info.format = 0;
+    file = sf_open(path.toLocal8Bit().data(), SFM_READ, &info);
+    if (!file) {
+	cerr << "ClipMixer::loadClipData: Failed to open file path \""
+             << path << "\": " << sf_strerror(file) << endl;
+	return false;
+    }
+
+    tmpFrames = (float *)malloc(info.frames * info.channels * sizeof(float));
+    if (!tmpFrames) {
+        cerr << "ClipMixer::loadClipData: malloc(" << info.frames * info.channels * sizeof(float) << ") failed" << endl;
+        return false;
+    }
+
+    sf_readf_float(file, tmpFrames, info.frames);
+    sf_close(file);
+
+    m_clipData = (float *)malloc(info.frames * sizeof(float));
+    if (!m_clipData) {
+        cerr << "ClipMixer::loadClipData: malloc(" << info.frames * sizeof(float) << ") failed" << endl;
+	free(tmpFrames);
+	return false;
+    }
+
+    for (i = 0; i < info.frames; ++i) {
+	int j;
+	m_clipData[i] = 0.0f;
+	for (j = 0; j < info.channels; ++j) {
+	    m_clipData[i] += tmpFrames[i * info.channels + j] * float(level);
+	}
+    }
+
+    free(tmpFrames);
+
+    m_clipLength = info.frames;
+    m_clipF0 = f0;
+    m_clipRate = info.samplerate;
+
+    return true;
+}
+
+void
+ClipMixer::reset()
+{
+    m_playing.clear();
+}
+
+double
+ClipMixer::getResampleRatioFor(double frequency)
+{
+    if (!m_clipData || !m_clipRate) return 1.0;
+    double pitchRatio = m_clipF0 / frequency;
+    double resampleRatio = m_sampleRate / m_clipRate;
+    return pitchRatio * resampleRatio;
+}
+
+sv_frame_t
+ClipMixer::getResampledClipDuration(double frequency)
+{
+    return sv_frame_t(ceil(double(m_clipLength) * getResampleRatioFor(frequency)));
+}
+
+void
+ClipMixer::mix(float **toBuffers, 
+               float gain,
+               std::vector<NoteStart> newNotes, 
+               std::vector<NoteEnd> endingNotes)
+{
+    foreach (NoteStart note, newNotes) {
+        if (note.frequency > 20 && 
+            note.frequency < 5000) {
+            m_playing.push_back(note);
+        }
+    }
+
+    std::vector<NoteStart> remaining;
+
+    float *levels = new float[m_channels];
+
+#ifdef DEBUG_CLIP_MIXER
+    cerr << "ClipMixer::mix: have " << m_playing.size() << " playing note(s)"
+         << " and " << endingNotes.size() << " note(s) ending here"
+         << endl;
+#endif
+
+    foreach (NoteStart note, m_playing) {
+
+        for (int c = 0; c < m_channels; ++c) {
+            levels[c] = note.level * gain;
+        }
+        if (note.pan != 0.0 && m_channels == 2) {
+            levels[0] *= 1.0f - note.pan;
+            levels[1] *= note.pan + 1.0f;
+        }
+
+        sv_frame_t start = note.frameOffset;
+        sv_frame_t durationHere = m_blockSize;
+        if (start > 0) durationHere = m_blockSize - start;
+
+        bool ending = false;
+
+        foreach (NoteEnd end, endingNotes) {
+            if (end.frequency == note.frequency && 
+                end.frameOffset >= start &&
+                end.frameOffset <= m_blockSize) {
+                ending = true;
+                durationHere = end.frameOffset;
+                if (start > 0) durationHere = end.frameOffset - start;
+                break;
+            }
+        }
+
+        sv_frame_t clipDuration = getResampledClipDuration(note.frequency);
+        if (start + clipDuration > 0) {
+            if (start < 0 && start + clipDuration < durationHere) {
+                durationHere = start + clipDuration;
+            }
+            if (durationHere > 0) {
+                mixNote(toBuffers,
+                        levels,
+                        note.frequency,
+                        start < 0 ? -start : 0,
+                        start > 0 ?  start : 0,
+                        durationHere,
+                        ending);
+            }
+        }
+
+        if (!ending) {
+            NoteStart adjusted = note;
+            adjusted.frameOffset -= m_blockSize;
+            remaining.push_back(adjusted);
+        }
+    }
+
+    delete[] levels;
+
+    m_playing = remaining;
+}
+
+void
+ClipMixer::mixNote(float **toBuffers,
+                   float *levels,
+                   float frequency,
+                   sv_frame_t sourceOffset,
+                   sv_frame_t targetOffset,
+                   sv_frame_t sampleCount,
+                   bool isEnd)
+{
+    if (!m_clipData) return;
+
+    double ratio = getResampleRatioFor(frequency);
+    
+    double releaseTime = 0.01;
+    sv_frame_t releaseSampleCount = sv_frame_t(round(releaseTime * m_sampleRate));
+    if (releaseSampleCount > sampleCount) {
+        releaseSampleCount = sampleCount;
+    }
+    double releaseFraction = 1.0/double(releaseSampleCount);
+
+    for (sv_frame_t i = 0; i < sampleCount; ++i) {
+
+        sv_frame_t s = sourceOffset + i;
+
+        double os = double(s) / ratio;
+        sv_frame_t osi = sv_frame_t(floor(os));
+
+        //!!! just linear interpolation for now (same as SV's sample
+        //!!! player). a small sinc kernel would be better and
+        //!!! probably "good enough"
+        double value = 0.0;
+        if (osi < m_clipLength) {
+            value += m_clipData[osi];
+        }
+        if (osi + 1 < m_clipLength) {
+            value += (m_clipData[osi + 1] - m_clipData[osi]) * (os - double(osi));
+        }
+         
+        if (isEnd && i + releaseSampleCount > sampleCount) {
+            value *= releaseFraction * double(sampleCount - i); // linear ramp for release
+        }
+
+        for (int c = 0; c < m_channels; ++c) {
+            toBuffers[c][targetOffset + i] += float(levels[c] * value);
+        }
+    }
+}
+
+