view base/Resampler.cpp @ 335:02d2ad95ea52 spectrogram-cache-rejig

* Get storage advice for each cache in an FFT data server.  Allows us to be
  more confident about the actual memory situation and cut over from memory
  to disc part way through an FFT calculation if necessary.  StorageAdviser
  is now a bit too optimistic though (it's too keen to allocate large numbers
  of small blocks in memory).

/* -*- 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>

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

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

    size_t resampleInterleaved(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 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);
    }
}

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

    size_t 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 (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];
        }
    }
    
    size_t gen = resampleInterleaved(m_iin, m_iout, incount, ratio, final);

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

    return gen;
}

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

    size_t 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);

    //!!! check err, respond appropriately

    return data.output_frames_gen;
}

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

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

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);
}

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

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