annotate data/model/FFTModel.cpp @ 1520:954d0cf29ca7 import-audio-data

Switch the normalisation option in WritableWaveFileModel from normalising on read to normalising on write, so that the saved file is already normalised and therefore can be read again without having to remember to normalise it

/* -*- 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.
    
    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 "FFTModel.h"
#include "DenseTimeValueModel.h"

#include "base/Profiler.h"
#include "base/Pitch.h"
#include "base/HitCount.h"
#include "base/Debug.h"

#include <algorithm>

#include <cassert>
#include <deque>

using namespace std;

static HitCount inSmallCache("FFTModel: Small FFT cache");
static HitCount inSourceCache("FFTModel: Source data cache");

FFTModel::FFTModel(const DenseTimeValueModel *model,
                   int channel,
                   WindowType windowType,
                   int windowSize,
                   int windowIncrement,
                   int fftSize) :
    m_model(model),
    m_channel(channel),
    m_windowType(windowType),
    m_windowSize(windowSize),
    m_windowIncrement(windowIncrement),
    m_fftSize(fftSize),
    m_windower(windowType, windowSize),
    m_fft(fftSize),
    m_cacheWriteIndex(0),
    m_cacheSize(3)
{
    while (m_cached.size() < m_cacheSize) {
        m_cached.push_back({ -1, cvec(m_fftSize / 2 + 1) });
    }
    
    if (m_windowSize > m_fftSize) {
        SVCERR << "ERROR: FFTModel::FFTModel: window size (" << m_windowSize
               << ") must be at least FFT size (" << m_fftSize << ")" << endl;
        throw invalid_argument("FFTModel window size must be at least FFT size");
    }

    m_fft.initFloat();

    connect(model, SIGNAL(modelChanged()), this, SIGNAL(modelChanged()));
    connect(model, SIGNAL(modelChangedWithin(sv_frame_t, sv_frame_t)),
            this, SIGNAL(modelChangedWithin(sv_frame_t, sv_frame_t)));
}

FFTModel::~FFTModel()
{
}

void
FFTModel::sourceModelAboutToBeDeleted()
{
    if (m_model) {
        SVDEBUG << "FFTModel[" << this << "]::sourceModelAboutToBeDeleted(" << m_model << ")" << endl;
        m_model = 0;
    }
}

int
FFTModel::getWidth() const
{
    if (!m_model) return 0;
    return int((m_model->getEndFrame() - m_model->getStartFrame())
               / m_windowIncrement) + 1;
}

int
FFTModel::getHeight() const
{
    return m_fftSize / 2 + 1;
}

QString
FFTModel::getBinName(int n) const
{
    sv_samplerate_t sr = getSampleRate();
    if (!sr) return "";
    QString name = tr("%1 Hz").arg((n * sr) / ((getHeight()-1) * 2));
    return name;
}

FFTModel::Column
FFTModel::getColumn(int x) const
{
    auto cplx = getFFTColumn(x);
    Column col;
    col.reserve(cplx.size());
    for (auto c: cplx) col.push_back(abs(c));
    return col;
}

FFTModel::Column
FFTModel::getPhases(int x) const
{
    auto cplx = getFFTColumn(x);
    Column col;
    col.reserve(cplx.size());
    for (auto c: cplx) {
        col.push_back(arg(c));
    }
    return col;
}

float
FFTModel::getMagnitudeAt(int x, int y) const
{
    if (x < 0 || x >= getWidth() || y < 0 || y >= getHeight()) return 0.f;
    auto col = getFFTColumn(x);
    return abs(col[y]);
}

float
FFTModel::getMaximumMagnitudeAt(int x) const
{
    Column col(getColumn(x));
    float max = 0.f;
    int n = int(col.size());
    for (int i = 0; i < n; ++i) {
        if (col[i] > max) max = col[i];
    }
    return max;
}

float
FFTModel::getPhaseAt(int x, int y) const
{
    if (x < 0 || x >= getWidth() || y < 0 || y >= getHeight()) return 0.f;
    return arg(getFFTColumn(x)[y]);
}

void
FFTModel::getValuesAt(int x, int y, float &re, float &im) const
{
    auto col = getFFTColumn(x);
    re = col[y].real();
    im = col[y].imag();
}

bool
FFTModel::getMagnitudesAt(int x, float *values, int minbin, int count) const
{
    if (count == 0) count = getHeight();
    auto col = getFFTColumn(x);
    for (int i = 0; i < count; ++i) {
        values[i] = abs(col[minbin + i]);
    }
    return true;
}

bool
FFTModel::getPhasesAt(int x, float *values, int minbin, int count) const
{
    if (count == 0) count = getHeight();
    auto col = getFFTColumn(x);
    for (int i = 0; i < count; ++i) {
        values[i] = arg(col[minbin + i]);
    }
    return true;
}

bool
FFTModel::getValuesAt(int x, float *reals, float *imags, int minbin, int count) const
{
    if (count == 0) count = getHeight();
    auto col = getFFTColumn(x);
    for (int i = 0; i < count; ++i) {
        reals[i] = col[minbin + i].real();
    }
    for (int i = 0; i < count; ++i) {
        imags[i] = col[minbin + i].imag();
    }
    return true;
}

FFTModel::fvec
FFTModel::getSourceSamples(int column) const
{
    // m_fftSize may be greater than m_windowSize, but not the reverse

//    cerr << "getSourceSamples(" << column << ")" << endl;
    
    auto range = getSourceSampleRange(column);
    auto data = getSourceData(range);

    int off = (m_fftSize - m_windowSize) / 2;

    if (off == 0) {
        return data;
    } else {
        vector<float> pad(off, 0.f);
        fvec padded;
        padded.reserve(m_fftSize);
        padded.insert(padded.end(), pad.begin(), pad.end());
        padded.insert(padded.end(), data.begin(), data.end());
        padded.insert(padded.end(), pad.begin(), pad.end());
        return padded;
    }
}

FFTModel::fvec
FFTModel::getSourceData(pair<sv_frame_t, sv_frame_t> range) const
{
//    cerr << "getSourceData(" << range.first << "," << range.second
//         << "): saved range is (" << m_savedData.range.first
//         << "," << m_savedData.range.second << ")" << endl;

    if (m_savedData.range == range) {
        inSourceCache.hit();
        return m_savedData.data;
    }

    Profiler profiler("FFTModel::getSourceData (cache miss)");
    
    if (range.first < m_savedData.range.second &&
        range.first >= m_savedData.range.first &&
        range.second > m_savedData.range.second) {

        inSourceCache.partial();
        
        sv_frame_t discard = range.first - m_savedData.range.first;

        fvec data;
        data.reserve(range.second - range.first);

        data.insert(data.end(),
                    m_savedData.data.begin() + discard,
                    m_savedData.data.end());

        fvec rest = getSourceDataUncached
            ({ m_savedData.range.second, range.second });

        data.insert(data.end(), rest.begin(), rest.end());
        
        m_savedData = { range, data };
        return data;

    } else {

        inSourceCache.miss();
        
        auto data = getSourceDataUncached(range);
        m_savedData = { range, data };
        return data;
    }
}

FFTModel::fvec
FFTModel::getSourceDataUncached(pair<sv_frame_t, sv_frame_t> range) const
{
    Profiler profiler("FFTModel::getSourceDataUncached");
    
    decltype(range.first) pfx = 0;
    if (range.first < 0) {
        pfx = -range.first;
        range = { 0, range.second };
    }

    auto data = m_model->getData(m_channel,
                                 range.first,
                                 range.second - range.first);

    if (data.empty()) {
        SVDEBUG << "NOTE: empty source data for range (" << range.first << ","
                << range.second << ") (model end frame "
                << m_model->getEndFrame() << ")" << endl;
    }
    
    // don't return a partial frame
    data.resize(range.second - range.first, 0.f);

    if (pfx > 0) {
        vector<float> pad(pfx, 0.f);
        data.insert(data.begin(), pad.begin(), pad.end());
    }
    
    if (m_channel == -1) {
        int channels = m_model->getChannelCount();
        if (channels > 1) {
            int n = int(data.size());
            float factor = 1.f / float(channels);
            // use mean instead of sum for fft model input
            for (int i = 0; i < n; ++i) {
                data[i] *= factor;
            }
        }
    }
    
    return data;
}

const FFTModel::cvec &
FFTModel::getFFTColumn(int n) const
{
    // The small cache (i.e. the m_cached deque) is for cases where
    // values are looked up individually, and for e.g. peak-frequency
    // spectrograms where values from two consecutive columns are
    // needed at once. This cache gets essentially no hits when
    // scrolling through a magnitude spectrogram, but 95%+ hits with a
    // peak-frequency spectrogram.
    for (const auto &incache : m_cached) {
        if (incache.n == n) {
            inSmallCache.hit();
            return incache.col;
        }
    }
    inSmallCache.miss();

    Profiler profiler("FFTModel::getFFTColumn (cache miss)");
    
    auto samples = getSourceSamples(n);
    m_windower.cut(samples.data());
    breakfastquay::v_fftshift(samples.data(), m_fftSize);

    cvec &col = m_cached[m_cacheWriteIndex].col;
    
    m_fft.forwardInterleaved(samples.data(),
                             reinterpret_cast<float *>(col.data()));

    m_cached[m_cacheWriteIndex].n = n;

    m_cacheWriteIndex = (m_cacheWriteIndex + 1) % m_cacheSize;

    return col;
}

bool
FFTModel::estimateStableFrequency(int x, int y, double &frequency)
{
    if (!isOK()) return false;

    frequency = double(y * getSampleRate()) / m_fftSize;

    if (x+1 >= getWidth()) return false;

    // At frequency f, a phase shift of 2pi (one cycle) happens in 1/f sec.
    // At hopsize h and sample rate sr, one hop happens in h/sr sec.
    // At window size w, for bin b, f is b*sr/w.
    // thus 2pi phase shift happens in w/(b*sr) sec.
    // We need to know what phase shift we expect from h/sr sec.
    // -> 2pi * ((h/sr) / (w/(b*sr)))
    //  = 2pi * ((h * b * sr) / (w * sr))
    //  = 2pi * (h * b) / w.

    double oldPhase = getPhaseAt(x, y);
    double newPhase = getPhaseAt(x+1, y);

    int incr = getResolution();

    double expectedPhase = oldPhase + (2.0 * M_PI * y * incr) / m_fftSize;

    double phaseError = princarg(newPhase - expectedPhase);

    // The new frequency estimate based on the phase error resulting
    // from assuming the "native" frequency of this bin

    frequency =
        (getSampleRate() * (expectedPhase + phaseError - oldPhase)) /
        (2.0 * M_PI * incr);

    return true;
}

FFTModel::PeakLocationSet
FFTModel::getPeaks(PeakPickType type, int x, int ymin, int ymax) const
{
    Profiler profiler("FFTModel::getPeaks");

    FFTModel::PeakLocationSet peaks;
    if (!isOK()) return peaks;

    if (ymax == 0 || ymax > getHeight() - 1) {
        ymax = getHeight() - 1;
    }

    if (type == AllPeaks) {
        int minbin = ymin;
        if (minbin > 0) minbin = minbin - 1;
        int maxbin = ymax;
        if (maxbin < getHeight() - 1) maxbin = maxbin + 1;
        const int n = maxbin - minbin + 1;
        float *values = new float[n];
        getMagnitudesAt(x, values, minbin, maxbin - minbin + 1);
        for (int bin = ymin; bin <= ymax; ++bin) {
            if (bin == minbin || bin == maxbin) continue;
            if (values[bin - minbin] > values[bin - minbin - 1] &&
                values[bin - minbin] > values[bin - minbin + 1]) {
                peaks.insert(bin);
            }
        }
        delete[] values;
        return peaks;
    }

    Column values = getColumn(x);
    int nv = int(values.size());

    float mean = 0.f;
    for (int i = 0; i < nv; ++i) mean += values[i];
    if (nv > 0) mean = mean / float(values.size());
    
    // For peak picking we use a moving median window, picking the
    // highest value within each continuous region of values that
    // exceed the median.  For pitch adaptivity, we adjust the window
    // size to a roughly constant pitch range (about four tones).

    sv_samplerate_t sampleRate = getSampleRate();

    deque<float> window;
    vector<int> inrange;
    float dist = 0.5;

    int medianWinSize = getPeakPickWindowSize(type, sampleRate, ymin, dist);
    int halfWin = medianWinSize/2;

    int binmin;
    if (ymin > halfWin) binmin = ymin - halfWin;
    else binmin = 0;

    int binmax;
    if (ymax + halfWin < nv) binmax = ymax + halfWin;
    else binmax = nv - 1;

    int prevcentre = 0;

    for (int bin = binmin; bin <= binmax; ++bin) {

        float value = values[bin];

        window.push_back(value);

        // so-called median will actually be the dist*100'th percentile
        medianWinSize = getPeakPickWindowSize(type, sampleRate, bin, dist);
        halfWin = medianWinSize/2;

        while ((int)window.size() > medianWinSize) {
            window.pop_front();
        }

        int actualSize = int(window.size());

        if (type == MajorPitchAdaptivePeaks) {
            if (ymax + halfWin < nv) binmax = ymax + halfWin;
            else binmax = nv - 1;
        }

        deque<float> sorted(window);
        sort(sorted.begin(), sorted.end());
        float median = sorted[int(float(sorted.size()) * dist)];

        int centrebin = 0;
        if (bin > actualSize/2) centrebin = bin - actualSize/2;
        
        while (centrebin > prevcentre || bin == binmin) {

            if (centrebin > prevcentre) ++prevcentre;

            float centre = values[prevcentre];

            if (centre > median) {
                inrange.push_back(centrebin);
            }

            if (centre <= median || centrebin+1 == nv) {
                if (!inrange.empty()) {
                    int peakbin = 0;
                    float peakval = 0.f;
                    for (int i = 0; i < (int)inrange.size(); ++i) {
                        if (i == 0 || values[inrange[i]] > peakval) {
                            peakval = values[inrange[i]];
                            peakbin = inrange[i];
                        }
                    }
                    inrange.clear();
                    if (peakbin >= ymin && peakbin <= ymax) {
                        peaks.insert(peakbin);
                    }
                }
            }

            if (bin == binmin) break;
        }
    }

    return peaks;
}

int
FFTModel::getPeakPickWindowSize(PeakPickType type, sv_samplerate_t sampleRate,
                                int bin, float &percentile) const
{
    percentile = 0.5;
    if (type == MajorPeaks) return 10;
    if (bin == 0) return 3;

    double binfreq = (sampleRate * bin) / m_fftSize;
    double hifreq = Pitch::getFrequencyForPitch(73, 0, binfreq);

    int hibin = int(lrint((hifreq * m_fftSize) / sampleRate));
    int medianWinSize = hibin - bin;
    if (medianWinSize < 3) medianWinSize = 3;

    percentile = 0.5f + float(binfreq / sampleRate);

    return medianWinSize;
}

FFTModel::PeakSet
FFTModel::getPeakFrequencies(PeakPickType type, int x,
                             int ymin, int ymax) const
{
    Profiler profiler("FFTModel::getPeakFrequencies");

    PeakSet peaks;
    if (!isOK()) return peaks;
    PeakLocationSet locations = getPeaks(type, x, ymin, ymax);

    sv_samplerate_t sampleRate = getSampleRate();
    int incr = getResolution();

    // This duplicates some of the work of estimateStableFrequency to
    // allow us to retrieve the phases in two separate vertical
    // columns, instead of jumping back and forth between columns x and
    // x+1, which may be significantly slower if re-seeking is needed

    vector<float> phases;
    for (PeakLocationSet::iterator i = locations.begin();
         i != locations.end(); ++i) {
        phases.push_back(getPhaseAt(x, *i));
    }

    int phaseIndex = 0;
    for (PeakLocationSet::iterator i = locations.begin();
         i != locations.end(); ++i) {
        double oldPhase = phases[phaseIndex];
        double newPhase = getPhaseAt(x+1, *i);
        double expectedPhase = oldPhase + (2.0 * M_PI * *i * incr) / m_fftSize;
        double phaseError = princarg(newPhase - expectedPhase);
        double frequency =
            (sampleRate * (expectedPhase + phaseError - oldPhase))
            / (2 * M_PI * incr);
        peaks[*i] = frequency;
        ++phaseIndex;
    }

    return peaks;
}