view data/model/FFTModel.h @ 490:c3fb8258e34d

* Make it possible to import an entire session from an RDF document.
  However, at the moment the timings of events appear to be constrained
  by how far the audio decoder has got through its audio file at the
  time the event is queried -- need to investigate.

/* -*- 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.
*/

#ifndef _FFT_MODEL_H_
#define _FFT_MODEL_H_

#include "data/fft/FFTDataServer.h"
#include "DenseThreeDimensionalModel.h"

#include <set>
#include <map>

/**
 * An implementation of DenseThreeDimensionalModel that makes FFT data
 * derived from a DenseTimeValueModel available as a generic data
 * grid.  The FFT data is acquired using FFTDataServer.  Note that any
 * of the accessor functions may throw AllocationFailed if a cache
 * resize fails.
 */

class FFTModel : public DenseThreeDimensionalModel
{
    Q_OBJECT

public:
    /**
     * Construct an FFT model derived from the given
     * DenseTimeValueModel, with the given window parameters and FFT
     * size (which may exceed the window size, for zero-padded FFTs).
     * 
     * If the model has multiple channels use only the given channel,
     * unless the channel is -1 in which case merge all available
     * channels.
     * 
     * If polar is true, the data will normally be retrieved from the
     * FFT model in magnitude/phase form; otherwise it will normally
     * be retrieved in "cartesian" real/imaginary form.  The results
     * should be the same either way, but a "polar" model addressed in
     * "cartesian" form or vice versa may suffer a performance
     * penalty.
     *
     * The fillFromColumn argument gives a hint that the FFT data
     * server should aim to start calculating FFT data at that column
     * number if possible, as that is likely to be requested first.
     */
    FFTModel(const DenseTimeValueModel *model,
             int channel,
             WindowType windowType,
             size_t windowSize,
             size_t windowIncrement,
             size_t fftSize,
             bool polar,
             StorageAdviser::Criteria criteria = StorageAdviser::NoCriteria,
             size_t fillFromColumn = 0);
    ~FFTModel();

    float getMagnitudeAt(size_t x, size_t y) {
        return m_server->getMagnitudeAt(x << m_xshift, y << m_yshift);
    }
    float getNormalizedMagnitudeAt(size_t x, size_t y) {
        return m_server->getNormalizedMagnitudeAt(x << m_xshift, y << m_yshift);
    }
    float getMaximumMagnitudeAt(size_t x) {
        return m_server->getMaximumMagnitudeAt(x << m_xshift);
    }
    float getPhaseAt(size_t x, size_t y) {
        return m_server->getPhaseAt(x << m_xshift, y << m_yshift);
    }
    void getValuesAt(size_t x, size_t y, float &real, float &imaginary) {
        m_server->getValuesAt(x << m_xshift, y << m_yshift, real, imaginary);
    }
    bool isColumnAvailable(size_t x) const {
        return m_server->isColumnReady(x << m_xshift);
    }

    float getMagnitudesAt(size_t x, float *values, size_t minbin = 0, size_t count = 0) {
        return m_server->getMagnitudesAt(x << m_xshift, values, minbin << m_yshift, count, getYRatio());
    }
    float getNormalizedMagnitudesAt(size_t x, float *values, size_t minbin = 0, size_t count = 0) {
        return m_server->getNormalizedMagnitudesAt(x << m_xshift, values, minbin << m_yshift, count, getYRatio());
    }
    float getPhasesAt(size_t x, float *values, size_t minbin = 0, size_t count = 0) {
        return m_server->getPhasesAt(x << m_xshift, values, minbin << m_yshift, count, getYRatio());
    }

    size_t getFillExtent() const { return m_server->getFillExtent(); }

    // DenseThreeDimensionalModel and Model methods:
    //
    virtual size_t getWidth() const {
        return m_server->getWidth() >> m_xshift;
    }
    virtual size_t getHeight() const {
        // If there is no y-shift, the server's height (based on its
        // fftsize/2 + 1) is correct.  If there is a shift, then the
        // server is using a larger fft size than we want, so we shift
        // it right as many times as necessary, but then we need to
        // re-add the "+1" part (because ((fftsize*2)/2 + 1) / 2 !=
        // fftsize/2 + 1).
        return (m_server->getHeight() >> m_yshift) + (m_yshift > 0 ? 1 : 0);
    }
    virtual float getValueAt(size_t x, size_t y) const {
        return const_cast<FFTModel *>(this)->getMagnitudeAt(x, y);
    }
    virtual bool isOK() const {
        return m_server && m_server->getModel();
    }
    virtual size_t getStartFrame() const {
        return 0;
    }
    virtual size_t getEndFrame() const {
        return getWidth() * getResolution() + getResolution();
    }
    virtual size_t getSampleRate() const;
    virtual size_t getResolution() const {
        return m_server->getWindowIncrement() << m_xshift;
    }
    virtual size_t getYBinCount() const {
        return getHeight();
    }
    virtual float getMinimumLevel() const {
        return 0.f; // Can't provide
    }
    virtual float getMaximumLevel() const {
        return 1.f; // Can't provide
    }
    virtual void getColumn(size_t x, Column &result) const;
    virtual QString getBinName(size_t n) const;

    virtual bool shouldUseLogValueScale() const {
        return true; // Although obviously it's up to the user...
    }

    /**
     * Calculate an estimated frequency for a stable signal in this
     * bin, using phase unwrapping.  This will be completely wrong if
     * the signal is not stable here.
     */
    virtual bool estimateStableFrequency(size_t x, size_t y, float &frequency);

    enum PeakPickType
    {
        AllPeaks,                /// Any bin exceeding its immediate neighbours
        MajorPeaks,              /// Peaks picked using sliding median window
        MajorPitchAdaptivePeaks  /// Bigger window for higher frequencies
    };

    typedef std::set<size_t> PeakLocationSet;
    typedef std::map<size_t, float> PeakSet;

    /**
     * Return locations of peak bins in the range [ymin,ymax].  If
     * ymax is zero, getHeight()-1 will be used.
     */
    virtual PeakLocationSet getPeaks(PeakPickType type, size_t x,
                                     size_t ymin = 0, size_t ymax = 0);

    /**
     * Return locations and estimated stable frequencies of peak bins.
     */
    virtual PeakSet getPeakFrequencies(PeakPickType type, size_t x,
                                       size_t ymin = 0, size_t ymax = 0);

    virtual int getCompletion() const { return m_server->getFillCompletion(); }

    virtual Model *clone() const;

    virtual void suspend() { m_server->suspend(); }
    virtual void suspendWrites() { m_server->suspendWrites(); }
    virtual void resume() { m_server->resume(); }

    QString getTypeName() const { return tr("FFT"); }

public slots:
    void sourceModelAboutToBeDeleted();

private:
    FFTModel(const FFTModel &); // not implemented
    FFTModel &operator=(const FFTModel &); // not implemented

    FFTDataServer *m_server;
    int m_xshift;
    int m_yshift;

    FFTDataServer *getServer(const DenseTimeValueModel *,
                             int, WindowType, size_t, size_t, size_t,
                             bool, StorageAdviser::Criteria, size_t);

    size_t getPeakPickWindowSize(PeakPickType type, size_t sampleRate,
                                 size_t bin, float &percentile) const;

    size_t getYRatio() {
        size_t ys = m_yshift;
        size_t r = 1;
        while (ys) { --ys; r <<= 1; }
        return r;
    }
};

#endif