view data/model/FFTModel.h @ 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.)
author Chris Cannam
date Fri, 14 Nov 2014 13:51:33 +0000
parents 59e7fe1b1003
children cc27f35aa75c
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/* -*- 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,
             int windowSize,
             int windowIncrement,
             int fftSize,
             bool polar,
             StorageAdviser::Criteria criteria = StorageAdviser::NoCriteria,
             int fillFromColumn = 0);
    ~FFTModel();

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

    inline bool getMagnitudesAt(int x, float *values, int minbin = 0, int count = 0) {
        return m_server->getMagnitudesAt(x << m_xshift, values, minbin << m_yshift, count, getYRatio());
    }
    inline bool getNormalizedMagnitudesAt(int x, float *values, int minbin = 0, int count = 0) {
        return m_server->getNormalizedMagnitudesAt(x << m_xshift, values, minbin << m_yshift, count, getYRatio());
    }
    inline bool getPhasesAt(int x, float *values, int minbin = 0, int count = 0) {
        return m_server->getPhasesAt(x << m_xshift, values, minbin << m_yshift, count, getYRatio());
    }
    inline bool getValuesAt(int x, float *reals, float *imaginaries, int minbin = 0, int count = 0) {
        return m_server->getValuesAt(x << m_xshift, reals, imaginaries, minbin << m_yshift, count, getYRatio());
    }

    inline int getFillExtent() const { return m_server->getFillExtent(); }

    // DenseThreeDimensionalModel and Model methods:
    //
    inline virtual int getWidth() const {
        return m_server->getWidth() >> m_xshift;
    }
    inline virtual int 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(int x, int y) const {
        return const_cast<FFTModel *>(this)->getMagnitudeAt(x, y);
    }
    virtual bool isOK() const {
        return m_server && m_server->getModel();
    }
    virtual int getStartFrame() const {
        return 0;
    }
    virtual int getEndFrame() const {
        return getWidth() * getResolution() + getResolution();
    }
    virtual int getSampleRate() const;
    virtual int getResolution() const {
        return m_server->getWindowIncrement() << m_xshift;
    }
    virtual int 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 Column getColumn(int x) const;
    virtual QString getBinName(int 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(int x, int 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<int> PeakLocationSet; // bin
    typedef std::map<int, float> PeakSet; // bin -> freq

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

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

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

    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, int, int, int,
                             bool, StorageAdviser::Criteria, int);

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

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

#endif