annotate data/fft/FFTCache.h @ 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 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_CACHE_H_
#define _FFT_CACHE_H_

#include <cstdlib>
#include <cmath>

#include <stdint.h>

class FFTCache
{
public:
    virtual ~FFTCache() { }

    virtual size_t getWidth() const = 0;
    virtual size_t getHeight() const = 0;
	
    virtual void resize(size_t width, size_t height) = 0;
    virtual void reset() = 0; // zero-fill or 1-fill as appropriate without changing size
	
    virtual float getMagnitudeAt(size_t x, size_t y) const = 0;
    virtual float getNormalizedMagnitudeAt(size_t x, size_t y) const = 0;
    virtual float getMaximumMagnitudeAt(size_t x) const = 0;
    virtual float getPhaseAt(size_t x, size_t y) const = 0;

    virtual void getValuesAt(size_t x, size_t y, float &real, float &imaginary) const = 0;

    virtual bool haveSetColumnAt(size_t x) const = 0;

    // may modify argument arrays
    virtual void setColumnAt(size_t x, float *mags, float *phases, float factor) = 0;

    // may modify argument arrays
    virtual void setColumnAt(size_t x, float *reals, float *imags) = 0;

    virtual void suspend() { }

    enum Type { MemoryCache, FileCache };
    virtual Type getType() = 0;

protected:
    FFTCache() { }
};


#endif