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livetrax/libs/vamp-pyin/MonoPitch.cpp

82 lines
2.5 KiB
C++

/* -*- c-basic-offset: 4 indent-tabs-mode: nil -*- vi:set ts=8 sts=4 sw=4: */
/*
pYIN - A fundamental frequency estimator for monophonic audio
Centre for Digital Music, Queen Mary, University 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.
*/
#include "MonoPitch.h"
#include "MonoPitchHMM.h"
#include <vector>
#include <cstdio>
#include <cmath>
#include <complex>
using std::vector;
using std::pair;
MonoPitch::MonoPitch() :
hmm()
{
}
MonoPitch::~MonoPitch()
{
}
const vector<float>
MonoPitch::process(const vector<vector<pair<double, double> > > pitchProb)
{
// std::cerr << "before observation prob calculation" << std::endl;
vector<vector<double> > obsProb;
for (size_t iFrame = 0; iFrame < pitchProb.size(); ++iFrame)
{
obsProb.push_back(hmm.calculateObsProb(pitchProb[iFrame]));
}
vector<double> *scale = new vector<double>(0);
vector<float> out;
// std::cerr << "before Viterbi decoding" << obsProb.size() << "ng" << obsProb[1].size() << std::endl;
vector<int> path = hmm.decodeViterbi(obsProb, scale);
// std::cerr << "after Viterbi decoding" << std::endl;
for (size_t iFrame = 0; iFrame < path.size(); ++iFrame)
{
// std::cerr << path[iFrame] << " " << hmm.m_freqs[path[iFrame]] << std::endl;
float hmmFreq = hmm.m_freqs[path[iFrame]];
float bestFreq = 0;
float leastDist = 10000;
if (hmmFreq > 0)
{
// This was a Yin estimate, so try to get original pitch estimate back
// ... a bit hacky, since we could have direclty saved the frequency
// that was assigned to the HMM bin in hmm.calculateObsProb -- but would
// have had to rethink the interface of that method.
for (size_t iPitch = 0; iPitch < pitchProb[iFrame].size(); ++iPitch)
{
float freq = 440. * std::pow(2, (pitchProb[iFrame][iPitch].first - 69)/12);
float dist = std::abs(hmmFreq-freq);
if (dist < leastDist)
{
leastDist = dist;
bestFreq = freq;
}
}
} else {
bestFreq = hmmFreq;
}
out.push_back(bestFreq);
}
delete scale;
return(out);
}