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livetrax/libs/qm-dsp/dsp/chromagram/Chromagram.cpp

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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 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.
*/
#include <iostream>
#include <cmath>
#include "maths/MathUtilities.h"
#include "Chromagram.h"
//----------------------------------------------------------------------------
Chromagram::Chromagram( ChromaConfig Config ) :
m_skGenerated(false)
{
initialise( Config );
}
int Chromagram::initialise( ChromaConfig Config )
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{
m_FMin = Config.min; // min freq
m_FMax = Config.max; // max freq
m_BPO = Config.BPO; // bins per octave
m_normalise = Config.normalise; // if frame normalisation is required
// No. of constant Q bins
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m_uK = ( unsigned int ) ceil( m_BPO * log(m_FMax/m_FMin)/log(2.0));
// Create array for chroma result
m_chromadata = new double[ m_BPO ];
// Create Config Structure for ConstantQ operator
CQConfig ConstantQConfig;
// Populate CQ config structure with parameters
// inherited from the Chroma config
ConstantQConfig.FS = Config.FS;
ConstantQConfig.min = m_FMin;
ConstantQConfig.max = m_FMax;
ConstantQConfig.BPO = m_BPO;
ConstantQConfig.CQThresh = Config.CQThresh;
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// Initialise ConstantQ operator
m_ConstantQ = new ConstantQ( ConstantQConfig );
// Initialise working arrays
m_frameSize = m_ConstantQ->getfftlength();
m_hopSize = m_ConstantQ->gethop();
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// Initialise FFT object
m_FFT = new FFTReal(m_frameSize);
m_FFTRe = new double[ m_frameSize ];
m_FFTIm = new double[ m_frameSize ];
m_CQRe = new double[ m_uK ];
m_CQIm = new double[ m_uK ];
m_window = 0;
m_windowbuf = 0;
return 1;
}
Chromagram::~Chromagram()
{
deInitialise();
}
int Chromagram::deInitialise()
{
delete[] m_windowbuf;
delete m_window;
delete [] m_chromadata;
delete m_FFT;
delete m_ConstantQ;
delete [] m_FFTRe;
delete [] m_FFTIm;
delete [] m_CQRe;
delete [] m_CQIm;
return 1;
}
//----------------------------------------------------------------------------------
// returns the absolute value of complex number xx + i*yy
double Chromagram::kabs(double xx, double yy)
{
double ab = sqrt(xx*xx + yy*yy);
return(ab);
}
//-----------------------------------------------------------------------------------
void Chromagram::unityNormalise(double *src)
{
double min, max;
double val = 0;
MathUtilities::getFrameMinMax( src, m_BPO, & min, &max );
for( unsigned int i = 0; i < m_BPO; i++ )
{
val = src[ i ] / max;
src[ i ] = val;
}
}
double* Chromagram::process( const double *data )
{
if (!m_skGenerated) {
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// Generate CQ Kernel
m_ConstantQ->sparsekernel();
m_skGenerated = true;
}
if (!m_window) {
m_window = new Window<double>(HammingWindow, m_frameSize);
m_windowbuf = new double[m_frameSize];
}
for (int i = 0; i < m_frameSize; ++i) {
m_windowbuf[i] = data[i];
}
m_window->cut(m_windowbuf);
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m_FFT->forward(m_windowbuf, m_FFTRe, m_FFTIm);
return process(m_FFTRe, m_FFTIm);
}
double* Chromagram::process( const double *real, const double *imag )
{
if (!m_skGenerated) {
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// Generate CQ Kernel
m_ConstantQ->sparsekernel();
m_skGenerated = true;
}
// initialise chromadata to 0
for (unsigned i = 0; i < m_BPO; i++) m_chromadata[i] = 0;
double cmax = 0.0;
double cval = 0;
// Calculate ConstantQ frame
m_ConstantQ->process( real, imag, m_CQRe, m_CQIm );
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// add each octave of cq data into Chromagram
const unsigned octaves = (int)floor(double( m_uK/m_BPO))-1;
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for (unsigned octave = 0; octave <= octaves; octave++)
{
unsigned firstBin = octave*m_BPO;
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for (unsigned i = 0; i < m_BPO; i++)
{
m_chromadata[i] += kabs( m_CQRe[ firstBin + i ], m_CQIm[ firstBin + i ]);
}
}
MathUtilities::normalise(m_chromadata, m_BPO, m_normalise);
return m_chromadata;
}