view base/Resampler.cpp @ 1008:d9e0e59a1581

When using an aggregate model to pass data to a transform, zero-pad the shorter input to the duration of the longer rather than truncating the longer. (This is better behaviour for e.g. MATCH, and in any case the code was previously truncating incorrectly and ending up with garbage data at the end.)

/* -*- 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 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.
*/

/*
   This is a modified version of a source file from the 
   Rubber Band audio timestretcher library.
   This file copyright 2007 Chris Cannam.
*/

#include "Resampler.h"

#include <cstdlib>
#include <cmath>

#include <iostream>

#include <samplerate.h>

#include "Debug.h"

class Resampler::D
{
public:
    D(Quality quality, int channels, int chunkSize);
    ~D();

    int resample(float **in, float **out,
                    int incount, float ratio,
                    bool final);

    int resampleInterleaved(float *in, float *out,
                               int incount, float ratio,
                               bool final);

    void reset();

protected:
    SRC_STATE *m_src;
    float *m_iin;
    float *m_iout;
    int m_channels;
    int m_iinsize;
    int m_ioutsize;
};

Resampler::D::D(Quality quality, int channels, int chunkSize) :
    m_src(0),
    m_iin(0),
    m_iout(0),
    m_channels(channels),
    m_iinsize(0),
    m_ioutsize(0)
{
    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 (chunkSize > 0 && m_channels > 1) {
        //!!! alignment?
        m_iinsize = chunkSize * m_channels;
        m_ioutsize = chunkSize * 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);
    }
}

int
Resampler::D::resample(float **in, float **out,
                       int incount, float ratio,
                       bool final)
{
    if (m_channels == 1) {
        return resampleInterleaved(*in, *out, incount, ratio, final);
    }

    int outcount = lrintf(ceilf(incount * ratio));

    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 (int i = 0; i < incount; ++i) {
        for (int c = 0; c < m_channels; ++c) {
            m_iin[i * m_channels + c] = in[c][i];
        }
    }
    
    int gen = resampleInterleaved(m_iin, m_iout, incount, ratio, final);

    for (int i = 0; i < gen; ++i) {
        for (int c = 0; c < m_channels; ++c) {
            out[c][i] = m_iout[i * m_channels + c];
        }
    }

    return gen;
}

int
Resampler::D::resampleInterleaved(float *in, float *out,
                                  int incount, float ratio,
                                  bool final)
{
    SRC_DATA data;

    int outcount = lrintf(ceilf(incount * ratio));

    data.data_in = in;
    data.data_out = out;
    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);

    if (err) {
        cerr << "Resampler: ERROR: src_process returned error: " <<
            src_strerror(err) << endl;
        return 0;
    }

    if (data.input_frames_used != (int)incount) {
        cerr << "Resampler: NOTE: input_frames_used == " << data.input_frames_used << " (while incount = " << incount << ")" << endl;
    }

    return data.output_frames_gen;
}

void
Resampler::D::reset()
{
    src_reset(m_src);
}

Resampler::Resampler(Quality quality, int channels, int chunkSize)
{
    m_d = new D(quality, channels, chunkSize);
}

Resampler::~Resampler()
{
    delete m_d;
}

int 
Resampler::resample(float **in, float **out,
                    int incount, float ratio,
                    bool final)
{
    return m_d->resample(in, out, incount, ratio, final);
}

int 
Resampler::resampleInterleaved(float *in, float *out,
                    int incount, float ratio,
                    bool final)
{
    return m_d->resampleInterleaved(in, out, incount, ratio, final);
}

void
Resampler::reset()
{
    m_d->reset();
}