GetKeyMode.cpp

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/* -*- c-basic-offset: 4 indent-tabs-mode: nil -*-  vi:set ts=8 sts=4 sw=4: */
/*
    Copyright (c) 2005 Centre for Digital Music ( C4DM )
                       Queen Mary Univesrity of London
 
    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.
*/
// GetKeyMode.cpp: implementation of the CGetKeyMode class.
//
 
#include "GetKeyMode.h"
#include "maths/MathUtilities.h"
#include "base/Pitch.h"
 
#include <iostream>
 
#include <cstring>
#include <cstdlib>
 
// Chords profile
static double MajProfile[36] = 
{ 0.0384, 0.0629, 0.0258, 0.0121, 0.0146, 0.0106, 0.0364, 0.0610, 0.0267,
  0.0126, 0.0121, 0.0086, 0.0364, 0.0623, 0.0279, 0.0275, 0.0414, 0.0186, 
  0.0173, 0.0248, 0.0145, 0.0364, 0.0631, 0.0262, 0.0129, 0.0150, 0.0098,
  0.0312, 0.0521, 0.0235, 0.0129, 0.0142, 0.0095, 0.0289, 0.0478, 0.0239};
 
static double MinProfile[36] =
{ 0.0375, 0.0682, 0.0299, 0.0119, 0.0138, 0.0093, 0.0296, 0.0543, 0.0257,
  0.0292, 0.0519, 0.0246, 0.0159, 0.0234, 0.0135, 0.0291, 0.0544, 0.0248,
  0.0137, 0.0176, 0.0104, 0.0352, 0.0670, 0.0302, 0.0222, 0.0349, 0.0164,
  0.0174, 0.0297, 0.0166, 0.0222, 0.0401, 0.0202, 0.0175, 0.0270, 0.0146};
//
    

// Construction/Destruction
 
GetKeyMode::GetKeyMode( int sampleRate, float tuningFrequency,
                        double hpcpAverage, double medianAverage ) :
    m_hpcpAverage( hpcpAverage ),
    m_medianAverage( medianAverage ),
    m_ChrPointer(0),
    m_DecimatedBuffer(0),
    m_ChromaBuffer(0),
    m_MeanHPCP(0),
    m_MajCorr(0),
    m_MinCorr(0),
    m_Keys(0),
    m_MedianFilterBuffer(0),
    m_SortedBuffer(0),
    m_keyStrengths(0)
{
    m_DecimationFactor = 8;
        
    // Chromagram configuration parameters
    m_ChromaConfig.normalise = MathUtilities::NormaliseUnitMax;
    m_ChromaConfig.FS = lrint(sampleRate/(double)m_DecimationFactor);
    if (m_ChromaConfig.FS < 1) m_ChromaConfig.FS = 1;
 
    // Set C (= MIDI #12) as our base :
    // This implies that key = 1 => Cmaj, key = 12 => Bmaj, key = 13 => Cmin, etc.
    m_ChromaConfig.min = Pitch::getFrequencyForPitch
        (48, 0, tuningFrequency);
    m_ChromaConfig.max = Pitch::getFrequencyForPitch
        (96, 0, tuningFrequency);
 
    m_ChromaConfig.BPO = 36;
    m_ChromaConfig.CQThresh = 0.0054;
 
    // Chromagram inst.
    m_Chroma = new Chromagram( m_ChromaConfig );
 
    // Get calculated parameters from chroma object
    m_ChromaFrameSize = m_Chroma->getFrameSize();
    // override hopsize for this application
    m_ChromaHopSize = m_ChromaFrameSize;
    m_BPO = m_ChromaConfig.BPO;
 
//    std::cerr << "chroma frame size = " << m_ChromaFrameSize << ", decimation factor = " << m_DecimationFactor << " therefore block size = " << getBlockSize() << std::endl;
 
    // Chromagram average and estimated key median filter lengths
    m_ChromaBuffersize = (int)ceil( m_hpcpAverage * m_ChromaConfig.FS/m_ChromaFrameSize );
    m_MedianWinsize = (int)ceil( m_medianAverage * m_ChromaConfig.FS/m_ChromaFrameSize );
    
    // Reset counters
    m_bufferindex = 0;
    m_ChromaBufferFilling = 0;
    m_MedianBufferFilling = 0;
 
    // Spawn objectc/arrays
    m_DecimatedBuffer = new double[m_ChromaFrameSize];
    
    m_ChromaBuffer = new double[m_BPO * m_ChromaBuffersize];
    memset( m_ChromaBuffer, 0, sizeof(double) * m_BPO * m_ChromaBuffersize);
    
    m_MeanHPCP = new double[m_BPO];
    
    m_MajCorr = new double[m_BPO];
    m_MinCorr = new double[m_BPO];
    m_Keys  = new double[2*m_BPO];
    
    m_MedianFilterBuffer = new int[ m_MedianWinsize ];
    memset( m_MedianFilterBuffer, 0, sizeof(int)*m_MedianWinsize);
    
    m_SortedBuffer = new int[ m_MedianWinsize ];
    memset( m_SortedBuffer, 0, sizeof(int)*m_MedianWinsize);    
    
    m_Decimator = new Decimator
        ( m_ChromaFrameSize*m_DecimationFactor, m_DecimationFactor );
 
    m_keyStrengths = new double[24];
}
 
GetKeyMode::~GetKeyMode()
{
 
    delete m_Chroma;
    delete m_Decimator;
    
    delete [] m_DecimatedBuffer;
    delete [] m_ChromaBuffer;
    delete [] m_MeanHPCP;
    delete [] m_MajCorr;
    delete [] m_MinCorr;
    delete [] m_Keys;
    delete [] m_MedianFilterBuffer;
    delete [] m_SortedBuffer;
 
    delete[] m_keyStrengths;
}
 
double GetKeyMode::krumCorr(double *pData1, double *pData2, unsigned int length)
{
    double retVal= 0.0;
    
    double num = 0;
    double den = 0;
    double mX = MathUtilities::mean( pData1, length );
    double mY = MathUtilities::mean( pData2, length );
    
    double sum1 = 0;
    double sum2 = 0;
    
    for( unsigned int i = 0; i <length; i++ )
    {
        num += ( pData1[i] - mX ) * ( pData2[i] - mY );
 
        sum1 += ( (pData1[i]-mX) * (pData1[i]-mX) );
        sum2 += ( (pData2[i]-mY) * (pData2[i]-mY) );
    }
        
    den = sqrt(sum1 * sum2);
        
    if( den>0 )
        retVal = num/den;
    else
        retVal = 0;
 
 
    return retVal;
}
 
int GetKeyMode::process(double *PCMData)
{
    int key;
 
    unsigned int j,k;

    m_Decimator->process( PCMData, m_DecimatedBuffer);
 
    m_ChrPointer = m_Chroma->process( m_DecimatedBuffer );              
 
        
    // Move bins such that the centre of the base note is in the
    // middle of its three bins :
    // Added 21.11.07 by Chris Sutton based on debugging with Katy
    // Noland + comparison with Matlab equivalent.
    MathUtilities::circShift( m_ChrPointer, m_BPO, 1);
/*
    std::cout << "raw chroma: ";
    for (int ii = 0; ii < m_BPO; ++ii) {
      if (ii % (m_BPO/12) == 0) std::cout << "\n";
        std::cout << m_ChrPointer[ii] << " ";
    }
    std::cout << std::endl;
*/
    // populate hpcp values;
    int cbidx;
    for( j = 0; j < m_BPO; j++ )
    {
        cbidx = (m_bufferindex * m_BPO) + j;
        m_ChromaBuffer[ cbidx ] = m_ChrPointer[j];
    }
 
    //keep track of input buffers;
    if( m_bufferindex++ >= m_ChromaBuffersize - 1) 
        m_bufferindex = 0;
 
    // track filling of chroma matrix
    if( m_ChromaBufferFilling++ >= m_ChromaBuffersize)
        m_ChromaBufferFilling = m_ChromaBuffersize;
 
    //calculate mean            
    for( k = 0; k < m_BPO; k++ )
    {
        double mnVal = 0.0;
        for( j = 0; j < m_ChromaBufferFilling; j++ )
        {
            mnVal += m_ChromaBuffer[ k + (j*m_BPO) ];
        }
 
        m_MeanHPCP[k] = mnVal/(double)m_ChromaBufferFilling;
    }
 
 
    for( k = 0; k < m_BPO; k++ )
    {
        m_MajCorr[k] = krumCorr( m_MeanHPCP, MajProfile, m_BPO );
        m_MinCorr[k] = krumCorr( m_MeanHPCP, MinProfile, m_BPO );
 
        MathUtilities::circShift( MajProfile, m_BPO, 1 );
        MathUtilities::circShift( MinProfile, m_BPO, 1 );
    }
        
    for( k = 0; k < m_BPO; k++ )
    {
        m_Keys[k] = m_MajCorr[k];
        m_Keys[k+m_BPO] = m_MinCorr[k];
    }
 
    for (k = 0; k < 24; ++k) {
        m_keyStrengths[k] = 0;
    }
 
    for( k = 0; k < m_BPO*2; k++ )
    {
        int idx = k / (m_BPO/12);
        int rem = k % (m_BPO/12);
        if (rem == 0 || m_Keys[k] > m_keyStrengths[idx]) {
            m_keyStrengths[idx] = m_Keys[k];
        }
 
//        m_keyStrengths[k/(m_BPO/12)] += m_Keys[k];
    }
 
/*
  std::cout << "raw keys: ";
  for (int ii = 0; ii < 2*m_BPO; ++ii) {
      if (ii % (m_BPO/12) == 0) std::cout << "\n";
      std::cout << m_Keys[ii] << " ";
  }
  std::cout << std::endl;
 
  std::cout << "key strengths: ";
  for (int ii = 0; ii < 24; ++ii) {
      if (ii % 6 == 0) std::cout << "\n";
      std::cout << m_keyStrengths[ii] << " ";
  }
  std::cout << std::endl;
*/
    double dummy;
    // '1 +' because we number keys 1-24, not 0-23.
    key = 1 + (int)ceil( (double)MathUtilities::getMax( m_Keys, 2* m_BPO, &dummy )/3 );
 
//    std::cout << "key pre-sorting: " << key << std::endl;
 
 
    //Median filtering
 
    // track Median buffer initial filling
    if( m_MedianBufferFilling++ >= m_MedianWinsize)
        m_MedianBufferFilling = m_MedianWinsize;
                
    //shift median buffer
    for( k = 1; k < m_MedianWinsize; k++ )
    {
        m_MedianFilterBuffer[ k - 1 ] = m_MedianFilterBuffer[ k ];
    }
 
    //write new key value into median buffer
    m_MedianFilterBuffer[ m_MedianWinsize - 1 ] = key;
 
 
    //Copy median into sorting buffer, reversed
    unsigned int ijx = 0;
    for( k = 0; k < m_MedianWinsize; k++ )
    {
        m_SortedBuffer[k] = m_MedianFilterBuffer[m_MedianWinsize-1-ijx];
        ijx++;
    }
 
    qsort(m_SortedBuffer, m_MedianBufferFilling, sizeof(unsigned int),
          MathUtilities::compareInt);
/*
  std::cout << "sorted: ";
  for (int ii = 0; ii < m_MedianBufferFilling; ++ii) {
  std::cout << m_SortedBuffer[ii] << " ";
  }
  std::cout << std::endl;
*/
    int sortlength = m_MedianBufferFilling;
    int midpoint = (int)ceil((double)sortlength/2);
 
//  std::cout << "midpoint = " << midpoint << endl;
 
    if( midpoint <= 0 )
        midpoint = 1;
 
    key = m_SortedBuffer[midpoint-1];
 
// std::cout << "returning key = " << key << endl;
 
    return key;
}
 
 
bool GetKeyMode::isModeMinor( int key )
{ 
    return (key > 12);
}