annotate data/fft/FFTDataServer.h @ 154:6ec58bb8f729

* Suspend/resume fft data server write activity while reading from a server
  to repaint the spectrogram display.  Makes a significant improvement to
  the otherwise dreadful responsiveness of spectrogram display.

/* -*- 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_DATA_SERVER_H_
#define _FFT_DATA_SERVER_H_

#include "base/Window.h"
#include "base/Thread.h"

#include <fftw3.h>

#include <QMutex>
#include <QWaitCondition>
#include <QString>

#include <vector>
#include <deque>

class DenseTimeValueModel;
class FFTCache;

class FFTDataServer
{
public:
    static FFTDataServer *getInstance(const DenseTimeValueModel *model,
                                      int channel,
                                      WindowType windowType,
                                      size_t windowSize,
                                      size_t windowIncrement,
                                      size_t fftSize,
                                      bool polar,
                                      size_t fillFromColumn = 0);

    static FFTDataServer *getFuzzyInstance(const DenseTimeValueModel *model,
                                           int channel,
                                           WindowType windowType,
                                           size_t windowSize,
                                           size_t windowIncrement,
                                           size_t fftSize,
                                           bool polar,
                                           size_t fillFromColumn = 0);

    static void claimInstance(FFTDataServer *);
    static void releaseInstance(FFTDataServer *);

    const DenseTimeValueModel *getModel() const { return m_model; }
    int        getChannel() const { return m_channel; }
    WindowType getWindowType() const { return m_windower.getType(); }
    size_t     getWindowSize() const { return m_windowSize; }
    size_t     getWindowIncrement() const { return m_windowIncrement; }
    size_t     getFFTSize() const { return m_fftSize; }
    bool       getPolar() const { return m_polar; }

    size_t     getWidth() const  { return m_width;  }
    size_t     getHeight() const { return m_height; }

    float      getMagnitudeAt(size_t x, size_t y);
    float      getNormalizedMagnitudeAt(size_t x, size_t y);
    float      getMaximumMagnitudeAt(size_t x);
    float      getPhaseAt(size_t x, size_t y);
    void       getValuesAt(size_t x, size_t y, float &real, float &imaginary);
    bool       isColumnReady(size_t x);

    void       suspend();
    void       resume(); // also happens automatically if new data needed

    // Convenience functions:

    bool isLocalPeak(size_t x, size_t y) {
        float mag = getMagnitudeAt(x, y);
        if (y > 0 && mag < getMagnitudeAt(x, y - 1)) return false;
        if (y < getHeight()-1 && mag < getMagnitudeAt(x, y + 1)) return false;
        return true;
    }
    bool isOverThreshold(size_t x, size_t y, float threshold) {
        return getMagnitudeAt(x, y) > threshold;
    }

    size_t getFillCompletion() const;
    size_t getFillExtent() const;

private:
    FFTDataServer(QString fileBaseName,
                  const DenseTimeValueModel *model,
                  int channel,
                  WindowType windowType,
                  size_t windowSize,
                  size_t windowIncrement,
                  size_t fftSize,
                  bool polar,
                  size_t fillFromColumn = 0);

    virtual ~FFTDataServer();

    FFTDataServer(const FFTDataServer &); // not implemented
    FFTDataServer &operator=(const FFTDataServer &); // not implemented

    typedef float fftsample;

    QString m_fileBaseName;
    const DenseTimeValueModel *m_model;
    int m_channel;

    Window<fftsample> m_windower;

    size_t m_windowSize;
    size_t m_windowIncrement;
    size_t m_fftSize;
    bool m_polar;

    size_t m_width;
    size_t m_height;
    size_t m_cacheWidth;

    typedef std::vector<FFTCache *> CacheVector;
    CacheVector m_caches;
    
    typedef std::deque<int> IntQueue;
    IntQueue m_dormantCaches;

    int m_lastUsedCache;
    FFTCache *getCache(size_t x, size_t &col) {
        col   = x % m_cacheWidth;
        int c = x / m_cacheWidth;
        // The only use of m_lastUsedCache without a lock is to
        // establish whether a cache has been created at all (they're
        // created on demand, but not destroyed until the server is).
        if (c == m_lastUsedCache) return m_caches[c];
        else return getCacheAux(c);
    }
    bool haveCache(size_t x) {
        int c = x / m_cacheWidth;
        if (c == m_lastUsedCache) return true;
        else return (m_caches[c] != 0);
    }
        
    FFTCache *getCacheAux(size_t c);
    QMutex m_writeMutex;
    QWaitCondition m_condition;

    fftsample *m_fftInput;
    fftwf_complex *m_fftOutput;
    float *m_workbuffer;
    fftwf_plan m_fftPlan;

    class FillThread : public Thread
    {
    public:
        FillThread(FFTDataServer &server, size_t fillFromColumn) :
            m_server(server), m_extent(0), m_completion(0),
            m_fillFrom(fillFromColumn) { }

        size_t getExtent() const { return m_extent; }
        size_t getCompletion() const { return m_completion ? m_completion : 1; }
        virtual void run();

    protected:
        FFTDataServer &m_server;
        size_t m_extent;
        size_t m_completion;
        size_t m_fillFrom;
    };

    bool m_exiting;
    bool m_suspended;
    FillThread *m_fillThread;

    void deleteProcessingData();
    void fillColumn(size_t x);

    QString generateFileBasename() const;
    static QString generateFileBasename(const DenseTimeValueModel *model,
                                        int channel,
                                        WindowType windowType,
                                        size_t windowSize,
                                        size_t windowIncrement,
                                        size_t fftSize,
                                        bool polar);

    typedef std::pair<FFTDataServer *, int> ServerCountPair;
    typedef std::map<QString, ServerCountPair> ServerMap;

    static ServerMap m_servers;
    static QMutex m_serverMapMutex;
    static FFTDataServer *findServer(QString); // call with serverMapMutex held
    static void purgeLimbo(int maxSize = 3); // call with serverMapMutex held
};

#endif