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livetrax/libs/qm-dsp/dsp/tempotracking/TempoTrack.cpp

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2016-10-05 18:16:44 -04:00
/* -*- 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.and Matthew Davies.
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
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COPYING included with this distribution for more information.
*/
#include "TempoTrack.h"
#include "maths/MathAliases.h"
#include "maths/MathUtilities.h"
#include <iostream>
#include <cassert>
//#define DEBUG_TEMPO_TRACK 1
#define RAY43VAL
//////////////////////////////////////////////////////////////////////
// Construction/Destruction
//////////////////////////////////////////////////////////////////////
TempoTrack::TempoTrack( TTParams Params )
{
m_tempoScratch = NULL;
m_rawDFFrame = NULL;
m_smoothDFFrame = NULL;
m_frameACF = NULL;
m_smoothRCF = NULL;
m_dataLength = 0;
m_winLength = 0;
m_lagLength = 0;
m_rayparam = 0;
m_sigma = 0;
m_DFWVNnorm = 0;
initialise( Params );
}
TempoTrack::~TempoTrack()
{
deInitialise();
}
void TempoTrack::initialise( TTParams Params )
{
m_winLength = Params.winLength;
m_lagLength = Params.lagLength;
m_rayparam = 43.0;
m_sigma = sqrt(3.9017);
m_DFWVNnorm = exp( ( log( 2.0 ) / m_rayparam ) * ( m_winLength + 2 ) );
m_rawDFFrame = new double[ m_winLength ];
m_smoothDFFrame = new double[ m_winLength ];
m_frameACF = new double[ m_winLength ];
m_tempoScratch = new double[ m_lagLength ];
m_smoothRCF = new double[ m_lagLength ];
m_DFFramer.configure( m_winLength, m_lagLength );
m_DFPParams.length = m_winLength;
m_DFPParams.AlphaNormParam = Params.alpha;
m_DFPParams.LPOrd = Params.LPOrd;
m_DFPParams.LPACoeffs = Params.LPACoeffs;
m_DFPParams.LPBCoeffs = Params.LPBCoeffs;
m_DFPParams.winPre = Params.WinT.pre;
m_DFPParams.winPost = Params.WinT.post;
m_DFPParams.isMedianPositive = true;
m_DFConditioning = new DFProcess( m_DFPParams );
// these are parameters for smoothing m_tempoScratch
m_RCFPParams.length = m_lagLength;
m_RCFPParams.AlphaNormParam = Params.alpha;
m_RCFPParams.LPOrd = Params.LPOrd;
m_RCFPParams.LPACoeffs = Params.LPACoeffs;
m_RCFPParams.LPBCoeffs = Params.LPBCoeffs;
m_RCFPParams.winPre = Params.WinT.pre;
m_RCFPParams.winPost = Params.WinT.post;
m_RCFPParams.isMedianPositive = true;
m_RCFConditioning = new DFProcess( m_RCFPParams );
}
void TempoTrack::deInitialise()
{
delete [] m_rawDFFrame;
delete [] m_smoothDFFrame;
delete [] m_smoothRCF;
delete [] m_frameACF;
delete [] m_tempoScratch;
delete m_DFConditioning;
delete m_RCFConditioning;
}
void TempoTrack::createCombFilter(double* Filter, int winLength, int /* TSig */, double beatLag)
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{
int i;
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if( beatLag == 0 )
{
for( i = 0; i < winLength; i++ )
{
Filter[ i ] = ( ( i + 1 ) / pow( m_rayparam, 2.0) ) * exp( ( -pow(( i + 1 ),2.0 ) / ( 2.0 * pow( m_rayparam, 2.0))));
}
}
else
{
m_sigma = beatLag/4;
for( i = 0; i < winLength; i++ )
{
double dlag = (double)(i+1) - beatLag;
Filter[ i ] = exp(-0.5 * pow(( dlag / m_sigma), 2.0) ) / (sqrt( 2 * PI) * m_sigma);
}
}
}
double TempoTrack::tempoMM(double* ACF, double* weight, int tsig)
{
double period = 0;
double maxValRCF = 0.0;
int maxIndexRCF = 0;
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double* pdPeaks;
int maxIndexTemp;
double maxValTemp;
int count;
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int numelem,i,j;
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int a, b;
for( i = 0; i < m_lagLength; i++ )
m_tempoScratch[ i ] = 0.0;
if( tsig == 0 )
{
//if time sig is unknown, use metrically unbiased version of Filterbank
numelem = 4;
}
else
{
numelem = tsig;
}
#ifdef DEBUG_TEMPO_TRACK
std::cerr << "tempoMM: m_winLength = " << m_winLength << ", m_lagLength = " << m_lagLength << ", numelem = " << numelem << std::endl;
#endif
for(i=1;i<m_lagLength-1;i++)
{
//first and last output values are left intentionally as zero
for (a=1;a<=numelem;a++)
{
for(b=(1-a);b<a;b++)
{
if( tsig == 0 )
{
m_tempoScratch[i] += ACF[a*(i+1)+b-1] * (1.0 / (2.0 * (double)a-1)) * weight[i];
}
else
{
m_tempoScratch[i] += ACF[a*(i+1)+b-1] * 1 * weight[i];
}
}
}
}
//////////////////////////////////////////////////
// MODIFIED BEAT PERIOD EXTRACTION //////////////
/////////////////////////////////////////////////
// find smoothed version of RCF ( as applied to Detection Function)
m_RCFConditioning->process( m_tempoScratch, m_smoothRCF);
if (tsig != 0) // i.e. in context dependent state
{
// NOW FIND MAX INDEX OF ACFOUT
for( i = 0; i < m_lagLength; i++)
{
if( m_tempoScratch[ i ] > maxValRCF)
{
maxValRCF = m_tempoScratch[ i ];
maxIndexRCF = i;
}
}
}
else // using rayleigh weighting
{
vector <vector<double> > rcfMat;
double sumRcf = 0.;
double maxVal = 0.;
// now find the two values which minimise rcfMat
double minVal = 0.;
int p_i = 1; // periodicity for row i;
int p_j = 1; //periodicity for column j;
for ( i=0; i<m_lagLength; i++)
{
m_tempoScratch[i] =m_smoothRCF[i];
}
// normalise m_tempoScratch so that it sums to zero.
for ( i=0; i<m_lagLength; i++)
{
sumRcf += m_tempoScratch[i];
}
for( i=0; i<m_lagLength; i++)
{
m_tempoScratch[i] /= sumRcf;
}
// create a matrix to store m_tempoScratchValues modified by log2 ratio
for ( i=0; i<m_lagLength; i++)
{
rcfMat.push_back ( vector<double>() ); // adds a new row...
}
for (i=0; i<m_lagLength; i++)
{
for (j=0; j<m_lagLength; j++)
{
rcfMat[i].push_back (0.);
}
}
// the 'i' and 'j' indices deliberately start from '1' and not '0'
for ( i=1; i<m_lagLength; i++)
{
for (j=1; j<m_lagLength; j++)
{
double log2PeriodRatio = log( static_cast<double>(i)/static_cast<double>(j) ) / log(2.0);
rcfMat[i][j] = ( abs(1.0-abs(log2PeriodRatio)) );
rcfMat[i][j] += ( 0.01*( 1./(m_tempoScratch[i]+m_tempoScratch[j]) ) );
}
}
// set diagonal equal to maximum value in rcfMat
// we don't want to pick one strong middle peak - we need a combination of two peaks.
for ( i=1; i<m_lagLength; i++)
{
for (j=1; j<m_lagLength; j++)
{
if (rcfMat[i][j] > maxVal)
{
maxVal = rcfMat[i][j];
}
}
}
for ( i=1; i<m_lagLength; i++)
{
rcfMat[i][i] = maxVal;
}
// now find the row and column number which minimise rcfMat
minVal = maxVal;
for ( i=1; i<m_lagLength; i++)
{
for ( j=1; j<m_lagLength; j++)
{
if (rcfMat[i][j] < minVal)
{
minVal = rcfMat[i][j];
p_i = i;
p_j = j;
}
}
}
// initially choose p_j (arbitrary) - saves on an else statement
int beatPeriod = p_j;
if (m_tempoScratch[p_i] > m_tempoScratch[p_j])
{
beatPeriod = p_i;
}
// now write the output
maxIndexRCF = static_cast<int>(beatPeriod);
}
double locked = 5168.f / maxIndexRCF;
if (locked >= 30 && locked <= 180) {
m_lockedTempo = locked;
}
#ifdef DEBUG_TEMPO_TRACK
std::cerr << "tempoMM: locked tempo = " << m_lockedTempo << std::endl;
#endif
if( tsig == 0 )
tsig = 4;
#ifdef DEBUG_TEMPO_TRACK
std::cerr << "tempoMM: maxIndexRCF = " << maxIndexRCF << std::endl;
#endif
if( tsig == 4 )
{
#ifdef DEBUG_TEMPO_TRACK
std::cerr << "tsig == 4" << std::endl;
#endif
pdPeaks = new double[ 4 ];
for( i = 0; i < 4; i++ ){ pdPeaks[ i ] = 0.0;}
pdPeaks[ 0 ] = ( double )maxIndexRCF + 1;
maxIndexTemp = 0;
maxValTemp = 0.0;
count = 0;
for( i = (2 * maxIndexRCF + 1) - 1; i < (2 * maxIndexRCF + 1) + 2; i++ )
{
if( ACF[ i ] > maxValTemp )
{
maxValTemp = ACF[ i ];
maxIndexTemp = count;
}
count++;
}
pdPeaks[ 1 ] = (double)( maxIndexTemp + 1 + ( (2 * maxIndexRCF + 1 ) - 2 ) + 1 )/2;
maxIndexTemp = 0;
maxValTemp = 0.0;
count = 0;
for( i = (3 * maxIndexRCF + 2 ) - 2; i < (3 * maxIndexRCF + 2 ) + 3; i++ )
{
if( ACF[ i ] > maxValTemp )
{
maxValTemp = ACF[ i ];
maxIndexTemp = count;
}
count++;
}
pdPeaks[ 2 ] = (double)( maxIndexTemp + 1 + ( (3 * maxIndexRCF + 2) - 4 ) + 1 )/3;
maxIndexTemp = 0;
maxValTemp = 0.0;
count = 0;
for( i = ( 4 * maxIndexRCF + 3) - 3; i < ( 4 * maxIndexRCF + 3) + 4; i++ )
{
if( ACF[ i ] > maxValTemp )
{
maxValTemp = ACF[ i ];
maxIndexTemp = count;
}
count++;
}
pdPeaks[ 3 ] = (double)( maxIndexTemp + 1 + ( (4 * maxIndexRCF + 3) - 9 ) + 1 )/4 ;
period = MathUtilities::mean( pdPeaks, 4 );
}
else
{
#ifdef DEBUG_TEMPO_TRACK
std::cerr << "tsig != 4" << std::endl;
#endif
pdPeaks = new double[ 3 ];
for( i = 0; i < 3; i++ ){ pdPeaks[ i ] = 0.0;}
pdPeaks[ 0 ] = ( double )maxIndexRCF + 1;
maxIndexTemp = 0;
maxValTemp = 0.0;
count = 0;
for( i = (2 * maxIndexRCF + 1) - 1; i < (2 * maxIndexRCF + 1) + 2; i++ )
{
if( ACF[ i ] > maxValTemp )
{
maxValTemp = ACF[ i ];
maxIndexTemp = count;
}
count++;
}
pdPeaks[ 1 ] = (double)( maxIndexTemp + 1 + ( (2 * maxIndexRCF + 1 ) - 2 ) + 1 )/2;
maxIndexTemp = 0;
maxValTemp = 0.0;
count = 0;
for( i = (3 * maxIndexRCF + 2 ) - 2; i < (3 * maxIndexRCF + 2 ) + 3; i++ )
{
if( ACF[ i ] > maxValTemp )
{
maxValTemp = ACF[ i ];
maxIndexTemp = count;
}
count++;
}
pdPeaks[ 2 ] = (double)( maxIndexTemp + 1 + ( (3 * maxIndexRCF + 2) - 4 ) + 1 )/3;
period = MathUtilities::mean( pdPeaks, 3 );
}
delete [] pdPeaks;
return period;
}
void TempoTrack::stepDetect( double* periodP, double* periodG, int currentIdx, int* flag )
{
double stepthresh = 1 * 3.9017;
if( *flag )
{
if(abs(periodG[ currentIdx ] - periodP[ currentIdx ]) > stepthresh)
{
// do nuffin'
}
}
else
{
if(fabs(periodG[ currentIdx ]-periodP[ currentIdx ]) > stepthresh)
{
*flag = 3;
}
}
}
void TempoTrack::constDetect( double* periodP, int currentIdx, int* flag )
{
double constthresh = 2 * 3.9017;
if( fabs( 2 * periodP[ currentIdx ] - periodP[ currentIdx - 1] - periodP[ currentIdx - 2] ) < constthresh)
{
*flag = 1;
}
else
{
*flag = 0;
}
}
int TempoTrack::findMeter(double *ACF, int len, double period)
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{
int i;
int p = (int)MathUtilities::round( period );
int tsig;
double Energy_3 = 0.0;
double Energy_4 = 0.0;
double temp3A = 0.0;
double temp3B = 0.0;
double temp4A = 0.0;
double temp4B = 0.0;
double* dbf = new double[ len ]; int t = 0;
for( int u = 0; u < len; u++ ){ dbf[ u ] = 0.0; }
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if( (double)len < 6 * p + 2 )
{
for( i = ( 3 * p - 2 ); i < ( 3 * p + 2 ) + 1; i++ )
{
temp3A += ACF[ i ];
dbf[ t++ ] = ACF[ i ];
}
for( i = ( 4 * p - 2 ); i < ( 4 * p + 2 ) + 1; i++ )
{
temp4A += ACF[ i ];
}
Energy_3 = temp3A;
Energy_4 = temp4A;
}
else
{
for( i = ( 3 * p - 2 ); i < ( 3 * p + 2 ) + 1; i++ )
{
temp3A += ACF[ i ];
}
for( i = ( 4 * p - 2 ); i < ( 4 * p + 2 ) + 1; i++ )
{
temp4A += ACF[ i ];
}
for( i = ( 6 * p - 2 ); i < ( 6 * p + 2 ) + 1; i++ )
{
temp3B += ACF[ i ];
}
for( i = ( 2 * p - 2 ); i < ( 2 * p + 2 ) + 1; i++ )
{
temp4B += ACF[ i ];
}
Energy_3 = temp3A + temp3B;
Energy_4 = temp4A + temp4B;
}
if (Energy_3 > Energy_4)
{
tsig = 3;
}
else
{
tsig = 4;
}
return tsig;
}
void TempoTrack::createPhaseExtractor(double *Filter, int /* winLength */, double period, int fsp, int lastBeat)
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{
int p = (int)MathUtilities::round( period );
int predictedOffset = 0;
#ifdef DEBUG_TEMPO_TRACK
std::cerr << "TempoTrack::createPhaseExtractor: period = " << period << ", p = " << p << std::endl;
#endif
if (p > 10000) {
std::cerr << "TempoTrack::createPhaseExtractor: WARNING! Highly implausible period value " << p << "!" << std::endl;
period = 5168 / 120;
}
double* phaseScratch = new double[ p*2 + 2 ];
for (int i = 0; i < p*2 + 2; ++i) phaseScratch[i] = 0.0;
if( lastBeat != 0 )
{
lastBeat = (int)MathUtilities::round((double)lastBeat );///(double)winLength);
predictedOffset = lastBeat + p - fsp;
if (predictedOffset < 0)
{
lastBeat = 0;
}
}
if( lastBeat != 0 )
{
int mu = p;
double sigma = (double)p/8;
double PhaseMin = 0.0;
double PhaseMax = 0.0;
int scratchLength = p*2;
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double temp = 0.0;
for( int i = 0; i < scratchLength; i++ )
{
phaseScratch[ i ] = exp( -0.5 * pow( ( i - mu ) / sigma, 2 ) ) / ( sqrt( 2*PI ) *sigma );
}
MathUtilities::getFrameMinMax( phaseScratch, scratchLength, &PhaseMin, &PhaseMax );
for(int i = 0; i < scratchLength; i ++)
{
temp = phaseScratch[ i ];
phaseScratch[ i ] = (temp - PhaseMin)/PhaseMax;
}
#ifdef DEBUG_TEMPO_TRACK
std::cerr << "predictedOffset = " << predictedOffset << std::endl;
#endif
int index = 0;
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for (int i = p - ( predictedOffset - 1); i < p + ( p - predictedOffset) + 1; i++)
{
#ifdef DEBUG_TEMPO_TRACK
std::cerr << "assigning to filter index " << index << " (size = " << p*2 << ")" << " value " << phaseScratch[i] << " from scratch index " << i << std::endl;
#endif
Filter[ index++ ] = phaseScratch[ i ];
}
}
else
{
for( int i = 0; i < p; i ++)
{
Filter[ i ] = 1;
}
}
delete [] phaseScratch;
}
int TempoTrack::phaseMM(double *DF, double *weighting, int winLength, double period)
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{
int alignment = 0;
int p = (int)MathUtilities::round( period );
double temp = 0.0;
double* y = new double[ winLength ];
double* align = new double[ p ];
for( int i = 0; i < winLength; i++ )
{
y[ i ] = (double)( -i + winLength )/(double)winLength;
y[ i ] = pow(y [i ],2.0); // raise to power 2.
}
for( int o = 0; o < p; o++ )
{
temp = 0.0;
for(int i = 1 + (o - 1); i< winLength; i += (p + 1))
{
temp = temp + DF[ i ] * y[ i ];
}
align[ o ] = temp * weighting[ o ];
}
double valTemp = 0.0;
for(int i = 0; i < p; i++)
{
if( align[ i ] > valTemp )
{
valTemp = align[ i ];
alignment = i;
}
}
delete [] y;
delete [] align;
return alignment;
}
int TempoTrack::beatPredict(int FSP0, double alignment, double period, int step )
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{
int beat = 0;
int p = (int)MathUtilities::round( period );
int align = (int)MathUtilities::round( alignment );
int FSP = (int)MathUtilities::round( FSP0 );
int FEP = FSP + ( step );
beat = FSP + align;
m_beats.push_back( beat );
while( beat + p < FEP )
{
beat += p;
m_beats.push_back( beat );
}
return beat;
}
vector<int> TempoTrack::process( vector <double> DF,
vector <double> *tempoReturn )
{
m_dataLength = DF.size();
m_lockedTempo = 0.0;
double period = 0.0;
int stepFlag = 0;
int constFlag = 0;
int FSP = 0;
int tsig = 0;
int lastBeat = 0;
vector <double> causalDF;
causalDF = DF;
//Prepare Causal Extension DFData
// int DFCLength = m_dataLength + m_winLength;
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for( int j = 0; j < m_winLength; j++ )
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{
causalDF.push_back( 0 );
}
double* RW = new double[ m_lagLength ];
for (int clear = 0; clear < m_lagLength; clear++){ RW[ clear ] = 0.0;}
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double* GW = new double[ m_lagLength ];
for (int clear = 0; clear < m_lagLength; clear++){ GW[ clear ] = 0.0;}
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double* PW = new double[ m_lagLength ];
for(int clear = 0; clear < m_lagLength; clear++){ PW[ clear ] = 0.0;}
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m_DFFramer.setSource( &causalDF[0], m_dataLength );
int TTFrames = m_DFFramer.getMaxNoFrames();
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#ifdef DEBUG_TEMPO_TRACK
std::cerr << "TTFrames = " << TTFrames << std::endl;
#endif
double* periodP = new double[ TTFrames ];
for(int clear = 0; clear < TTFrames; clear++){ periodP[ clear ] = 0.0;}
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double* periodG = new double[ TTFrames ];
for(int clear = 0; clear < TTFrames; clear++){ periodG[ clear ] = 0.0;}
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double* alignment = new double[ TTFrames ];
for(int clear = 0; clear < TTFrames; clear++){ alignment[ clear ] = 0.0;}
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m_beats.clear();
createCombFilter( RW, m_lagLength, 0, 0 );
int TTLoopIndex = 0;
for( int i = 0; i < TTFrames; i++ )
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{
m_DFFramer.getFrame( m_rawDFFrame );
m_DFConditioning->process( m_rawDFFrame, m_smoothDFFrame );
m_correlator.doAutoUnBiased( m_smoothDFFrame, m_frameACF, m_winLength );
periodP[ TTLoopIndex ] = tempoMM( m_frameACF, RW, 0 );
if( GW[ 0 ] != 0 )
{
periodG[ TTLoopIndex ] = tempoMM( m_frameACF, GW, tsig );
}
else
{
periodG[ TTLoopIndex ] = 0.0;
}
stepDetect( periodP, periodG, TTLoopIndex, &stepFlag );
if( stepFlag == 1)
{
constDetect( periodP, TTLoopIndex, &constFlag );
stepFlag = 0;
}
else
{
stepFlag -= 1;
}
if( stepFlag < 0 )
{
stepFlag = 0;
}
if( constFlag != 0)
{
tsig = findMeter( m_frameACF, m_winLength, periodP[ TTLoopIndex ] );
createCombFilter( GW, m_lagLength, tsig, periodP[ TTLoopIndex ] );
periodG[ TTLoopIndex ] = tempoMM( m_frameACF, GW, tsig );
period = periodG[ TTLoopIndex ];
#ifdef DEBUG_TEMPO_TRACK
std::cerr << "TempoTrack::process: constFlag == " << constFlag << ", TTLoopIndex = " << TTLoopIndex << ", period from periodG = " << period << std::endl;
#endif
createPhaseExtractor( PW, m_winLength, period, FSP, 0 );
constFlag = 0;
}
else
{
if( GW[ 0 ] != 0 )
{
period = periodG[ TTLoopIndex ];
#ifdef DEBUG_TEMPO_TRACK
std::cerr << "TempoTrack::process: GW[0] == " << GW[0] << ", TTLoopIndex = " << TTLoopIndex << ", period from periodG = " << period << std::endl;
#endif
if (period > 10000) {
std::cerr << "TempoTrack::process: WARNING! Highly implausible period value " << period << "!" << std::endl;
std::cerr << "periodG contains (of " << TTFrames << " frames): " << std::endl;
for (int i = 0; i < TTLoopIndex + 3 && i < TTFrames; ++i) {
std::cerr << i << " -> " << periodG[i] << std::endl;
}
std::cerr << "periodP contains (of " << TTFrames << " frames): " << std::endl;
for (int i = 0; i < TTLoopIndex + 3 && i < TTFrames; ++i) {
std::cerr << i << " -> " << periodP[i] << std::endl;
}
period = 5168 / 120;
}
createPhaseExtractor( PW, m_winLength, period, FSP, lastBeat );
}
else
{
period = periodP[ TTLoopIndex ];
#ifdef DEBUG_TEMPO_TRACK
std::cerr << "TempoTrack::process: GW[0] == " << GW[0] << ", TTLoopIndex = " << TTLoopIndex << ", period from periodP = " << period << std::endl;
#endif
createPhaseExtractor( PW, m_winLength, period, FSP, 0 );
}
}
alignment[ TTLoopIndex ] = phaseMM( m_rawDFFrame, PW, m_winLength, period );
lastBeat = beatPredict(FSP, alignment[ TTLoopIndex ], period, m_lagLength );
FSP += (m_lagLength);
if (tempoReturn) tempoReturn->push_back(m_lockedTempo);
TTLoopIndex++;
}
delete [] periodP;
delete [] periodG;
delete [] alignment;
delete [] RW;
delete [] GW;
delete [] PW;
return m_beats;
}