annotate dsp/onsets/DetectionFunction.cpp @ 13:f2b5c4251bf3

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/* -*- 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 copyright 2005-2006 Christian Landone.
    All rights reserved.
*/

#include "DetectionFunction.h"

//////////////////////////////////////////////////////////////////////
// Construction/Destruction
//////////////////////////////////////////////////////////////////////

DetectionFunction::DetectionFunction( DFConfig Config ) :
    m_window(0)
{
    m_magHistory = NULL;
    m_phaseHistory = NULL;
    m_phaseHistoryOld = NULL;

    initialise( Config );
}

DetectionFunction::~DetectionFunction()
{
    deInitialise();
}


void DetectionFunction::initialise( DFConfig Config )
{
    m_dataLength = Config.frameLength;
    m_halfLength = m_dataLength/2;
    m_DFType = Config.DFType;
    m_stepSecs = Config.stepSecs;
    m_stepSize = Config.stepSize;

    m_magHistory = new double[ m_halfLength ];
    memset(m_magHistory,0, m_halfLength*sizeof(double));
		
    m_phaseHistory = new double[ m_halfLength ];
    memset(m_phaseHistory,0, m_halfLength*sizeof(double));

    m_phaseHistoryOld = new double[ m_halfLength ];
    memset(m_phaseHistoryOld,0, m_halfLength*sizeof(double));

    m_phaseVoc = new PhaseVocoder;

    m_DFWindowedFrame = new double[ m_dataLength ];
    m_magnitude = new double[ m_halfLength ];
    m_thetaAngle = new double[ m_halfLength ];

    m_window = new Window<double>(HanningWindow, m_dataLength);
}

void DetectionFunction::deInitialise()
{
    delete [] m_magHistory ;
    delete [] m_phaseHistory ;
    delete [] m_phaseHistoryOld ;

    delete m_phaseVoc;

    delete [] m_DFWindowedFrame;
    delete [] m_magnitude;
    delete [] m_thetaAngle;

    delete m_window;
}

double DetectionFunction::process( double *TDomain )
{
    m_window->cut( TDomain, m_DFWindowedFrame );
	
    m_phaseVoc->process( m_dataLength, m_DFWindowedFrame, m_magnitude, m_thetaAngle );

    return runDF();
}

double DetectionFunction::process( double *magnitudes, double *phases )
{
    for (size_t i = 0; i < m_halfLength; ++i) {
        m_magnitude[i] = magnitudes[i];
        m_thetaAngle[i] = phases[i];
    }

    return runDF();
}

double DetectionFunction::runDF()
{
    double retVal = 0;

    switch( m_DFType )
    {
    case DF_HFC:
	retVal = HFC( m_halfLength, m_magnitude);
	break;
	
    case DF_SPECDIFF:
	retVal = specDiff( m_halfLength, m_magnitude);
	break;
	
    case DF_PHASEDEV:
	retVal = phaseDev( m_halfLength, m_magnitude, m_thetaAngle);
	break;
	
    case DF_COMPLEXSD:
	retVal = complexSD( m_halfLength, m_magnitude, m_thetaAngle);
	break;

    case DF_BROADBAND:
        retVal = broadband( m_halfLength, m_magnitude, m_thetaAngle);
    }
	
    return retVal;
}

double DetectionFunction::HFC(unsigned int length, double *src)
{
    unsigned int i;
    double val = 0;

    for( i = 0; i < length; i++)
    {
	val += src[ i ] * ( i + 1);
    }
    return val;
}

double DetectionFunction::specDiff(unsigned int length, double *src)
{
    unsigned int i;
    double val = 0.0;
    double temp = 0.0;
    double diff = 0.0;

    for( i = 0; i < length; i++)
    {
	temp = fabs( (src[ i ] * src[ i ]) - (m_magHistory[ i ] * m_magHistory[ i ]) );
		
	diff= sqrt(temp);

        // (See note in phaseDev below.)

        val += diff;

	m_magHistory[ i ] = src[ i ];
    }

    return val;
}


double DetectionFunction::phaseDev(unsigned int length, double *srcMagnitude, double *srcPhase)
{
    unsigned int i;
    double tmpPhase = 0;
    double tmpVal = 0;
    double val = 0;

    double dev = 0;

    for( i = 0; i < length; i++)
    {
	tmpPhase = (srcPhase[ i ]- 2*m_phaseHistory[ i ]+m_phaseHistoryOld[ i ]);
	dev = MathUtilities::princarg( tmpPhase );

        // A previous version of this code only counted the value here
        // if the magnitude exceeded 0.1.  My impression is that
        // doesn't greatly improve the results for "loud" music (so
        // long as the peak picker is reasonably sophisticated), but
        // does significantly damage its ability to work with quieter
        // music, so I'm removing it and counting the result always.
        // Same goes for the spectral difference measure above.
		
        tmpVal  = fabs(dev);
        val += tmpVal ;

	m_phaseHistoryOld[ i ] = m_phaseHistory[ i ] ;
	m_phaseHistory[ i ] = srcPhase[ i ];
    }
	
	
    return val;
}


double DetectionFunction::complexSD(unsigned int length, double *srcMagnitude, double *srcPhase)
{
    unsigned int i;
    double val = 0;
    double tmpPhase = 0;
    double tmpReal = 0;
    double tmpImag = 0;
   
    double dev = 0;
    ComplexData meas = ComplexData( 0, 0 );
    ComplexData j = ComplexData( 0, 1 );

    for( i = 0; i < length; i++)
    {
	tmpPhase = (srcPhase[ i ]- 2*m_phaseHistory[ i ]+m_phaseHistoryOld[ i ]);
	dev= MathUtilities::princarg( tmpPhase );
		
	meas = m_magHistory[i] - ( srcMagnitude[ i ] * exp( j * dev) );

	tmpReal = real( meas );
	tmpImag = imag( meas );

	val += sqrt( (tmpReal * tmpReal) + (tmpImag * tmpImag) );
		
	m_phaseHistoryOld[ i ] = m_phaseHistory[ i ] ;
	m_phaseHistory[ i ] = srcPhase[ i ];
	m_magHistory[ i ] = srcMagnitude[ i ];
    }

    return val;
}

double DetectionFunction::broadband(unsigned int length, double *srcMagnitude, double *srcPhase)
{
    double val = 0;
    for (unsigned int i = 0; i < length; ++i) {
        double sqrmag = srcMagnitude[i] * srcMagnitude[i];
        if (m_magHistory[i] > 0.0) {
            double diff = 10.0 * log10(sqrmag / m_magHistory[i]);
            if (diff > m_dbRise) val = val + 1;
        }
        m_magHistory[i] = sqrmag;
    }
    return val;
}        

double* DetectionFunction::getSpectrumMagnitude()
{
    return m_magnitude;
}