* Initial import

src/Resampler.cpp

@@ -0,0 +1,169 @@
+/* -*- c-basic-offset: 4 indent-tabs-mode: nil -*- vi:set ts=8 sts=4 sw=4: */
+
+/*
+    Rubber Band
+    An audio time-stretching and pitch-shifting library.
+    Copyright 2007 Chris Cannam.
+    
+    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 "Resampler.h"
+
+#include <cstdlib>
+#include <cmath>
+
+#include <iostream>
+
+
+#include <samplerate.h>
+
+namespace RubberBand {
+
+class Resampler::D
+{
+public:
+    D(Quality quality, size_t channels, size_t maxBufferSize);
+    ~D();
+
+    size_t resample(float **in, float **out,
+                    size_t incount, float ratio, bool final);
+
+    void reset();
+
+protected:
+    SRC_STATE *m_src;
+    float *m_iin;
+    float *m_iout;
+    size_t m_channels;
+    size_t m_iinsize;
+    size_t m_ioutsize;
+};
+
+Resampler::D::D(Quality quality, size_t channels, size_t maxBufferSize) :
+    m_src(0),
+    m_iin(0),
+    m_iout(0),
+    m_channels(channels),
+    m_iinsize(0),
+    m_ioutsize(0)
+{
+    std::cerr << "Resampler::Resampler: using libsamplerate implementation"
+              << std::endl;
+
+    int err = 0;
+    m_src = src_new(quality == Best ? SRC_SINC_BEST_QUALITY :
+                    quality == Fastest ? SRC_LINEAR :
+                    SRC_SINC_FASTEST,
+                    channels, &err);
+
+    //!!! check err, throw
+
+    if (maxBufferSize > 0 && m_channels > 1) {
+        //!!! alignment?
+        m_iinsize = maxBufferSize * m_channels;
+        m_ioutsize = maxBufferSize * m_channels * 2;
+        m_iin = (float *)malloc(m_iinsize * sizeof(float));
+        m_iout = (float *)malloc(m_ioutsize * sizeof(float));
+    }
+}
+
+Resampler::D::~D()
+{
+    src_delete(m_src);
+    if (m_iinsize > 0) {
+        free(m_iin);
+    }
+    if (m_ioutsize > 0) {
+        free(m_iout);
+    }
+}
+
+size_t
+Resampler::D::resample(float **in, float **out, size_t incount, float ratio,
+                       bool final)
+{
+    SRC_DATA data;
+
+    size_t outcount = lrintf(ceilf(incount * ratio));
+
+    if (m_channels == 1) {
+        data.data_in = *in;
+        data.data_out = *out;
+    } else {
+        if (incount * m_channels > m_iinsize) {
+            m_iinsize = incount * m_channels;
+            m_iin = (float *)realloc(m_iin, m_iinsize * sizeof(float));
+        }
+        if (outcount * m_channels > m_ioutsize) {
+            m_ioutsize = outcount * m_channels;
+            m_iout = (float *)realloc(m_iout, m_ioutsize * sizeof(float));
+        }
+        for (size_t i = 0; i < incount; ++i) {
+            for (size_t c = 0; c < m_channels; ++c) {
+                m_iin[i * m_channels + c] = in[c][i];
+            }
+        }
+        data.data_in = m_iin;
+        data.data_out = m_iout;
+    }
+
+    data.input_frames = incount;
+    data.output_frames = outcount;
+    data.src_ratio = ratio;
+    data.end_of_input = (final ? 1 : 0);
+
+    int err = src_process(m_src, &data);
+
+    //!!! check err, respond appropriately
+
+    if (m_channels > 1) {
+        for (size_t i = 0; i < data.output_frames_gen; ++i) {
+            for (size_t c = 0; c < m_channels; ++c) {
+                out[c][i] = m_iout[i * m_channels + c];
+            }
+        }
+    }
+
+    return data.output_frames_gen;
+}
+
+void
+Resampler::D::reset()
+{
+    src_reset(m_src);
+}
+
+} // end namespace
+
+
+namespace RubberBand {
+
+Resampler::Resampler(Quality quality, size_t channels, size_t maxBufferSize)
+{
+    m_d = new D(quality, channels, maxBufferSize);
+}
+
+Resampler::~Resampler()
+{
+    delete m_d;
+}
+
+size_t 
+Resampler::resample(float **in, float **out,
+                    size_t incount, float ratio, bool final)
+{
+    return m_d->resample(in, out, incount, ratio, final);
+}
+
+void
+Resampler::reset()
+{
+    m_d->reset();
+}
+
+}