1 files changed, 81 insertions, 0 deletions
diff --git a/libs/vamp-pyin/MonoPitch.cpp b/libs/vamp-pyin/MonoPitch.cpp
new file mode 100644
index 0000000000..01830f5419
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+++ b/libs/vamp-pyin/MonoPitch.cpp
@@ -0,0 +1,81 @@
+/* -*- 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);
+}