annotate dsp/onsets/DetectionFunction.h @ 96:88f3cfcff55f

A threshold (delta) is added in the peak picking parameters structure (PPickParams). It is used as an offset when computing the smoothed detection function. A constructor for the structure PPickParams is also added to set the parameters to 0 when a structure instance is created. Hence programmes using the peak picking parameter structure and which do not set the delta parameter (e.g. QM Vamp note onset detector) won't be affected by the modifications.

Functions modified:
- dsp/onsets/PeakPicking.cpp
- dsp/onsets/PeakPicking.h
- dsp/signalconditioning/DFProcess.cpp
- dsp/signalconditioning/DFProcess.h

/* -*- c-basic-offset: 4 indent-tabs-mode: nil -*-  vi:set ts=8 sts=4 sw=4: */

/*
    QM DSP Library

    Centre for Digital Music, Queen Mary, University of London.
    This file 2005-2006 Christian Landone.

    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 DETECTIONFUNCTION_H
#define DETECTIONFUNCTION_H

#include "maths/MathUtilities.h"
#include "maths/MathAliases.h"
#include "dsp/phasevocoder/PhaseVocoder.h"
#include "base/Window.h"

#define DF_HFC (1)
#define DF_SPECDIFF (2)
#define DF_PHASEDEV (3)
#define DF_COMPLEXSD (4)
#define DF_BROADBAND (5)

struct DFConfig{
    unsigned int stepSize; // DF step in samples
    unsigned int frameLength; // DF analysis window - usually 2*step
    int DFType; // type of detection function ( see defines )
    double dbRise; // only used for broadband df (and required for it)
    bool adaptiveWhitening; // perform adaptive whitening
    double whiteningRelaxCoeff; // if < 0, a sensible default will be used
    double whiteningFloor; // if < 0, a sensible default will be used
};

class DetectionFunction  
{
public:
    double* getSpectrumMagnitude();
    DetectionFunction( DFConfig Config );
    virtual ~DetectionFunction();
    double process( const double* TDomain );
    double process( const double* magnitudes, const double* phases );

private:
    void whiten();
    double runDF();

    double HFC( unsigned int length, double* src);
    double specDiff( unsigned int length, double* src);
    double phaseDev(unsigned int length, double *srcPhase);
    double complexSD(unsigned int length, double *srcMagnitude, double *srcPhase);
    double broadband(unsigned int length, double *srcMagnitude);
	
private:
    void initialise( DFConfig Config );
    void deInitialise();

    int m_DFType;
    unsigned int m_dataLength;
    unsigned int m_halfLength;
    unsigned int m_stepSize;
    double m_dbRise;
    bool m_whiten;
    double m_whitenRelaxCoeff;
    double m_whitenFloor;

    double* m_magHistory;
    double* m_phaseHistory;
    double* m_phaseHistoryOld;
    double* m_magPeaks;

    double* m_DFWindowedFrame; // Array for windowed analysis frame
    double* m_magnitude; // Magnitude of analysis frame ( frequency domain )
    double* m_thetaAngle;// Phase of analysis frame ( frequency domain )

    Window<double> *m_window;
    PhaseVocoder* m_phaseVoc;	// Phase Vocoder
};

#endif