view cpp-qm-dsp/ConstantQ.h @ 92:5a3163eff37a

A bit more on inverse

/* -*- c-basic-offset: 4 indent-tabs-mode: nil -*-  vi:set ts=8 sts=4 sw=4: */
/*
    Constant-Q library
    Copyright (c) 2013-2014 Queen Mary, University of London

    Permission is hereby granted, free of charge, to any person
    obtaining a copy of this software and associated documentation
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    of the Software, and to permit persons to whom the Software is
    furnished to do so, subject to the following conditions:

    The above copyright notice and this permission notice shall be
    included in all copies or substantial portions of the Software.

    THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
    EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
    MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
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    WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.

    Except as contained in this notice, the names of the Centre for
    Digital Music; Queen Mary, University of London; and Chris Cannam
    shall not be used in advertising or otherwise to promote the sale,
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*/

#ifndef CONSTANTQ_H
#define CONSTANTQ_H

#include "CQBase.h"
#include "CQKernel.h"

class Resampler;
class FFTReal;

/**
 * Calculate a complex sparse constant-Q representation from
 * time-domain input.
 *
 * For a real (magnitude-only) or interpolated representation, see
 * CQSpectrogram.
 */
class ConstantQ : public CQBase
{
public:
    ConstantQ(double sampleRate, 
	      double minFreq, double maxFreq, 
	      int binsPerOctave);
    virtual ~ConstantQ();

    virtual double getSampleRate() const { return m_sampleRate; }
    virtual int getBinsPerOctave() const { return m_binsPerOctave; }
    virtual int getOctaves() const { return m_octaves; }
    virtual int getTotalBins() const { return m_octaves * m_binsPerOctave; }
    virtual int getColumnHop() const { return m_p.fftHop / m_p.atomsPerFrame; }
    virtual int getLatency() const { return m_outputLatency; } 
    virtual double getMaxFrequency() const { return m_p.maxFrequency; }
    virtual double getMinFrequency() const;
    virtual double getBinFrequency(int bin) const;

    /**
     * Given a series of time-domain samples, return a series of
     * constant-Q columns. Any samples left over (that did not fit
     * into a constant-Q processing block) are saved for the next call
     * to process or getRemainingBlocks.
     *
     * Each column contains a series of constant-Q bin values ordered
     * from highest to lowest frequency.
     *
     * Columns are of variable height: each will contain at least
     * getBinsPerOctave() values, because the highest-frequency octave
     * is always present, but a second octave (if requested) will
     * appear only in alternate columns, a third octave only in every
     * fourth column, and so on.
     *
     * If you need a format in which all columns are of equal height
     * and every bin contains a value, use CQInterpolated instead of
     * ConstantQ.
     */
    ComplexBlock process(const RealSequence &);

    /**
     * Return the remaining constant-Q columns following the end of
     * processing. Any buffered input is padded so as to ensure that
     * all input provided to process() will have been returned.
     */
    ComplexBlock getRemainingOutput();

private:
    double m_sampleRate;
    double m_maxFrequency;
    double m_minFrequency;
    int m_binsPerOctave;
    int m_octaves;

    CQKernel *m_kernel;
    CQKernel::Properties m_p;
    int m_bigBlockSize;

    std::vector<Resampler *> m_decimators;
    std::vector<RealSequence> m_buffers;

    int m_outputLatency;

    FFTReal *m_fft;

    void initialise();
    ComplexBlock processOctaveBlock(int octave);
};

#endif