/home/maxime/Projets/Mixxx/1.10/mixxx/src/tonal/ChordExtractor.hxx

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/*
 * Copyright (c) 2001-2006 MUSIC TECHNOLOGY GROUP (MTG)
 *                         UNIVERSITAT POMPEU FABRA
 *
 *
 * 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.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 *
 */

#ifndef ChordExtractor_hxx
#define ChordExtractor_hxx

#include "DiscontinuousSegmentation.hxx"
#include "ChordSegmentator.hxx"
#include "ChordCorrelator.hxx"
#include "CircularPeakPicking.hxx"
#include "CircularPeaksToPCP.hxx"
#include "CircularPeakTunner.hxx"
#include "ConstantQFolder.hxx"
#include "ConstantQTransform.hxx"
#include "FourierTransform.hxx"
#include "InstantTunningEstimator.hxx"
#include "SemitoneCenterFinder.hxx"
#include "PCPSmother.hxx"

namespace Simac
{

class ChordExtractor
{
        double _sparseConstantQKernelThreshold;
        ConstantQTransform _constantQTransform;
        ConstantQFolder _constantQFolder;
        FourierTransform _fourierTransform;
        CircularPeakPicking _circularPeakPicking;
        InstantTunningEstimator _instantTunningEstimator;
        CircularPeakTunner _circularPeakTunner;
        CircularPeaksToPCP _circularPeaksToPCP;
        PCPSmother _filter;
        ChordCorrelator _chordCorrelator;
        ChordSegmentator _chordSegmentator;
        bool _tunningEnabled;
        bool _peakWindowingEnabled;
        double _hopRatio;
        unsigned _estimatedChord;
        unsigned _secondCandidate;
        double _squaredRootEnergy;
public:
        static double maximumFrequency(double sampleRate) { return sampleRate/2.1; } // Just below nyquist
        typedef float * AudioFrame;

        ChordExtractor(unsigned sampleRate=44100, double minimumFrequency=98, unsigned binsPerOctave=36)
                : _sparseConstantQKernelThreshold(0.0054)
                , _constantQTransform(sampleRate, minimumFrequency, maximumFrequency(sampleRate), binsPerOctave)
                , _constantQFolder(_constantQTransform.getK(), binsPerOctave)
                , _fourierTransform(_constantQTransform.getfftlength(),1,0)
                , _circularPeakPicking(binsPerOctave, /*scaling factor*/ 12.0/binsPerOctave)
                , _instantTunningEstimator(/*Inertia*/ 1.0)
                , _circularPeakTunner(/*reference tunning*/ 0.0)
                , _filter(0.7)
                , _tunningEnabled(true)
                , _peakWindowingEnabled(true)
                , _hopRatio(8.0) // On the original Chromagram cpp code was 32
                , _estimatedChord(0)
                , _secondCandidate(0)
        {
                _constantQTransform.sparsekernel(_sparseConstantQKernelThreshold);
                if (_peakWindowingEnabled)
                        _circularPeaksToPCP.activateWindowing();
        }
        ~ChordExtractor()
        {
        }

        // Accessors
        void filterInertia(double inertia)
        {
                _filter.inertia(inertia);
        }
        void enableTunning(bool tunningEnabled=true)  { _tunningEnabled=tunningEnabled; }
        void enablePeakWindowing(bool peakWindowingEnabled=true)  { _peakWindowingEnabled=peakWindowingEnabled; }
        void hopRatio(double hopRatio) { _hopRatio=hopRatio; }
        void segmentationMethod(double segmentationMethod) { _chordSegmentator.method(segmentationMethod); }

        unsigned hop() const {return _constantQTransform.getfftlength()/_hopRatio;}
        unsigned frameSize() const {return _constantQTransform.getfftlength();}

        void doIt(const AudioFrame & input, CLAM::TData & currentTime)
        {
                _squaredRootEnergy = 0.0;
                for (unsigned i=0; i<frameSize(); i++)
                        _squaredRootEnergy += input[i]*input[i];
                        
                _fourierTransform.doIt(input);
                _constantQTransform.doIt(_fourierTransform.spectrum());
                _constantQFolder.doIt(_constantQTransform.constantQSpectrum());
                _circularPeakPicking.doIt(_constantQFolder.chromagram());
                _instantTunningEstimator.doIt(_circularPeakPicking.output());
                _circularPeakTunner.doIt(_instantTunningEstimator.output().first, _circularPeakPicking.output());
                if (_tunningEnabled)
                        _circularPeaksToPCP.doIt(_circularPeakTunner.output());
                else
                        _circularPeaksToPCP.doIt(_circularPeakPicking.output());
                _filter.doIt(_circularPeaksToPCP.output());
                _chordCorrelator.doIt(_filter.output());
                estimateChord(_chordCorrelator.output());
                _chordSegmentator.doIt(currentTime, _chordCorrelator.output(), _estimatedChord, _secondCandidate);
        }
        void estimateChord(const ChordCorrelator::ChordCorrelation & correlation)
        {
                double maxCorrelation = 0;
                double underMaxCorrelation = 0;
                unsigned maxIndex = 0;
                unsigned underMaxIndex = 0;
                for (unsigned i=0; i<correlation.size(); i++)
                {
                        if (correlation[i]<underMaxCorrelation) continue;
                        if (correlation[i]<maxCorrelation)
                        {
                                underMaxIndex=i;
                                underMaxCorrelation=correlation[i];
                                continue;
                        }
                        underMaxIndex=maxIndex;
                        underMaxCorrelation=maxCorrelation;
                        maxIndex=i;
                        maxCorrelation=correlation[i];
                }
                _estimatedChord = maxIndex;
                _secondCandidate = underMaxIndex;
        }
        std::string chordRepresentation(unsigned chordIndex) const
        {
                return _chordCorrelator.chordRepresentation(chordIndex);
        }
        std::string root(unsigned chordIndex) const
        {
                return _chordCorrelator.root(chordIndex);
        }
        std::string mode(unsigned chordIndex) const
        {
                return _chordCorrelator.mode(chordIndex);
        }
        const std::string chordEstimation() const
        {
                const ChordCorrelator::ChordCorrelation & correlation = _chordCorrelator.output();
                double maxCorrelation=correlation[_estimatedChord];
                double underMaxCorrelation=correlation[_secondCandidate];
                if (maxCorrelation*0.7<=correlation[0]) return "None";
                bool estimationIsClear = maxCorrelation*0.9>underMaxCorrelation;
                std::ostringstream os;
                os << _chordCorrelator.chordRepresentation(_estimatedChord);
                if (!estimationIsClear) 
                        os << " [or "<< _chordCorrelator.chordRepresentation(_secondCandidate)<< "]";
                os << " (" << (correlation[0]/maxCorrelation) << ")";
                if (!estimationIsClear) 
                        os << " (" << (underMaxCorrelation/(underMaxCorrelation+maxCorrelation)) << ")";
                return os.str();
        }
        const std::vector<double> & chromagram() const
        {
                return _constantQFolder.chromagram();
        }
        const std::vector<double> & pcp() const
        {
                return _circularPeaksToPCP.output();
        }
        const std::vector<std::pair<double, double> > & peaks() const
        {
                return _circularPeakPicking.output();
        }
        const std::vector<double> & chordCorrelation() const
        {
                return _chordCorrelator.output();
        }
        const CLAM::DiscontinuousSegmentation & segmentation() const
        {
                return _chordSegmentator.segmentation();
        }
        const std::vector<unsigned> & chordIndexes() const
        {
                return _chordSegmentator.chordIndexes();
        }
        void clear()
        {
                _chordSegmentator.eraseAllSegments();
        }
        void closeLastSegment(CLAM::TData currentTime)
        {
                _chordSegmentator.closeLastSegment(currentTime);
        }
        double tunning() const {return _instantTunningEstimator.output().first; }
        double tunningStrength() const {return _instantTunningEstimator.output().second; }
        std::pair<double,double> instantTunning() const {return _instantTunningEstimator.instantTunning(); }
        double energy() const {return _squaredRootEnergy; }
        unsigned firstCandidate() const {return _estimatedChord;}
        unsigned secondCandidate() const {return _secondCandidate;}
        std::vector<double> spectrum() const {return _fourierTransform.spectrum(); }

};
}

#endif//ChordExtractor