annotate data/fft/FFTFileCacheReader.h @ 875:3e6ed8a8577b tonioni

Use a sparse time-value model only for outputs with fixed bin count of 1, not for those with unknown bin count.
(Precursor to using more than one model for outputs with unknown bin count)

/* -*- 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 2006-2009 Chris Cannam and QMUL.
    
    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_FILE_CACHE_READER_H_
#define _FFT_FILE_CACHE_READER_H_

#include "data/fileio/MatrixFile.h"
#include "FFTCacheReader.h"
#include "FFTCacheStorageType.h"

class FFTFileCacheWriter;

class FFTFileCacheReader : public FFTCacheReader
{
public:
    FFTFileCacheReader(FFTFileCacheWriter *);
    ~FFTFileCacheReader();

    size_t getWidth() const;
    size_t getHeight() const;
	
    float getMagnitudeAt(size_t x, size_t y) const;
    float getNormalizedMagnitudeAt(size_t x, size_t y) const;
    float getMaximumMagnitudeAt(size_t x) const;
    float getPhaseAt(size_t x, size_t y) const;

    void getValuesAt(size_t x, size_t y, float &real, float &imag) const;
    void getMagnitudesAt(size_t x, float *values, size_t minbin, size_t count, size_t step) const;

    bool haveSetColumnAt(size_t x) const;

    static size_t getCacheSize(size_t width, size_t height,
                               FFTCache::StorageType type);

    FFTCache::StorageType getStorageType() const { return m_storageType; }

protected:
    mutable char *m_readbuf;
    mutable size_t m_readbufCol;
    mutable size_t m_readbufWidth;
    mutable bool m_readbufGood;

    float getFromReadBufStandard(size_t x, size_t y) const {
        float v;
        if (m_readbuf &&
            (m_readbufCol == x || (m_readbufWidth > 1 && m_readbufCol+1 == x))) {
            v = ((float *)m_readbuf)[(x - m_readbufCol) * m_mfc->getHeight() + y];
            return v;
        } else {
            populateReadBuf(x);
            v = getFromReadBufStandard(x, y);
            return v;
        }
    }

    float getFromReadBufCompactUnsigned(size_t x, size_t y) const {
        float v;
        if (m_readbuf &&
            (m_readbufCol == x || (m_readbufWidth > 1 && m_readbufCol+1 == x))) {
            v = ((uint16_t *)m_readbuf)[(x - m_readbufCol) * m_mfc->getHeight() + y];
            return v;
        } else {
            populateReadBuf(x);
            v = getFromReadBufCompactUnsigned(x, y);
            return v;
        }
    }

    float getFromReadBufCompactSigned(size_t x, size_t y) const {
        float v;
        if (m_readbuf &&
            (m_readbufCol == x || (m_readbufWidth > 1 && m_readbufCol+1 == x))) {
            v = ((int16_t *)m_readbuf)[(x - m_readbufCol) * m_mfc->getHeight() + y];
            return v;
        } else {
            populateReadBuf(x);
            v = getFromReadBufCompactSigned(x, y);
            return v;
        }
    }

    void populateReadBuf(size_t x) const;

    float getNormalizationFactor(size_t col) const {
        size_t h = m_mfc->getHeight();
        if (h < m_factorSize) return 0;
        if (m_storageType != FFTCache::Compact) {
            return getFromReadBufStandard(col, h - 1);
        } else {
            union {
                float f;
                uint16_t u[2];
            } factor;
            if (!m_readbuf ||
                !(m_readbufCol == col ||
                  (m_readbufWidth > 1 && m_readbufCol+1 == col))) {
                populateReadBuf(col);
            }
            size_t ix = (col - m_readbufCol) * m_mfc->getHeight() + h;
            factor.u[0] = ((uint16_t *)m_readbuf)[ix - 2];
            factor.u[1] = ((uint16_t *)m_readbuf)[ix - 1];
            return factor.f;
        }
    }
 
    FFTCache::StorageType m_storageType;
    size_t m_factorSize;
    MatrixFile *m_mfc;
};

#endif