diff dsp/segmentation/ClusterMeltSegmenter.cpp @ 18:8e90a56b4b5f

* merge in segmentation code from soundbite plugin/library repository

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/dsp/segmentation/ClusterMeltSegmenter.cpp	Wed Jan 09 10:46:25 2008 +0000
@@ -0,0 +1,187 @@
+/*
+ *  ClusterMeltSegmenter.cpp
+ *  soundbite
+ *
+ *  Created by Mark Levy on 23/03/2006.
+ *  Copyright 2006 Centre for Digital Music, Queen Mary, University of London. All rights reserved.
+ *
+ */
+
+#include <cfloat>
+#include <cmath>
+
+#include "ClusterMeltSegmenter.h"
+#include "lib_constQ.h"
+#include "cluster_segmenter.h"
+#include "segment.h"
+
+ClusterMeltSegmenter::ClusterMeltSegmenter(ClusterMeltSegmenterParams params) : window(NULL),
+constq(NULL),
+featureType(params.featureType),
+windowSize(params.windowSize),
+hopSize(params.hopSize),
+fmin(params.fmin),
+fmax(params.fmax),
+nbins(params.nbins),
+ncomponents(params.ncomponents),	// NB currently not passed - no. of PCA components is set in cluser_segmenter.c
+nHMMStates(params.nHMMStates),
+nclusters(params.nclusters),
+histogramLength(params.histogramLength),
+neighbourhoodLimit(params.neighbourhoodLimit)
+{
+}
+
+void ClusterMeltSegmenter::initialise(int fs)
+{
+	samplerate = fs;
+	if (featureType != FEATURE_TYPE_UNKNOWN)
+	{
+		ncoeff = static_cast<int>(ceil(nbins * (log(fmax / static_cast<double>(fmin))) / log(2.0)));
+		constq = init_constQ(fmin, fmax, nbins, samplerate, ncoeff);	
+	}
+}
+
+ClusterMeltSegmenter::~ClusterMeltSegmenter() 
+{
+	delete [] window;
+	if (constq)
+		close_constQ(constq);
+}
+
+void ClusterMeltSegmenter::extractFeatures(double* samples, int nsamples)
+{
+	// create a new window if needed
+	if (!window || nsamples != windowLength)
+	{
+		if (window)
+			delete [] window;
+		window = hamming_p(nsamples);
+		windowLength = nsamples;
+	}	
+	
+	// copy the samples before windowing in case we need them for something else
+	double* frame = new double[nsamples];
+	for (int i = 0; i < nsamples; i++)
+		frame[i] = samples[i] * window[i];
+	
+	// extract const-Q
+	do_constQ(constq, frame, nsamples);
+	int ncq = constq->ncoeff;
+	
+	delete [] frame;
+	
+	if (ncq == ncoeff)		// else feature extraction failed
+	{
+		vector<double> cq(ncq);
+		for (int i = 0; i < ncq; i++)
+			cq[i] = constq->absconstQtransform[i];
+		features.push_back(cq);
+	}
+}
+
+void ClusterMeltSegmenter::segment(int m)
+{
+	nclusters = m;
+	segment();
+}
+
+void ClusterMeltSegmenter::setFeatures(const vector<vector<double> >& f)
+{
+	features = f;
+	featureType = FEATURE_TYPE_UNKNOWN;
+}
+
+void ClusterMeltSegmenter::segment()
+{
+	if (constq)
+	{
+		close_constQ(constq);		// finished extracting features
+		constq = NULL;
+	}
+	
+	// for now copy the features to a native array and use the existing C segmenter...
+	double** arrFeatures = new double*[features.size()];	
+	for (int i = 0; i < features.size(); i++)
+	{
+		if (featureType == FEATURE_TYPE_UNKNOWN)
+			arrFeatures[i] = new double[features[0].size()];
+		else
+			arrFeatures[i] = new double[ncoeff+1];	// allow space for the normalised envelope
+		for (int j = 0; j < ncoeff; j++)
+			arrFeatures[i][j] = features[i][j];	
+	}
+	
+	q = new int[features.size()];
+	
+	if (featureType == FEATURE_TYPE_UNKNOWN)
+		cluster_segment(q, arrFeatures, features.size(), features[0].size(), nHMMStates, histogramLength, 
+						nclusters, neighbourhoodLimit);
+	else
+		constq_segment(q, arrFeatures, features.size(), nbins, ncoeff, featureType, 
+					nHMMStates, histogramLength, nclusters, neighbourhoodLimit);
+	
+	// convert the cluster assignment sequence to a segmentation
+	makeSegmentation(q, features.size());		
+	
+	// de-allocate arrays
+	delete [] q;
+	for (int i = 0; i < features.size(); i++)
+		delete [] arrFeatures[i];
+	delete [] arrFeatures;
+	
+	// clear the features
+	clear();
+}
+
+void ClusterMeltSegmenter::makeSegmentation(int* q, int len)
+{
+	segmentation.segments.clear();
+	segmentation.nsegtypes = nclusters;
+	segmentation.samplerate = samplerate;
+	
+	Segment segment;
+	segment.start = 0;
+	segment.type = q[0];
+	
+	for (int i = 1; i < len; i++)
+	{
+		if (q[i] != q[i-1])
+		{
+			segment.end = i * getHopsize();
+			segmentation.segments.push_back(segment);
+			segment.type = q[i];
+			segment.start = segment.end;
+		}
+	}
+	segment.end = len * getHopsize();
+	segmentation.segments.push_back(segment);
+}
+
+/*
+void ClusterMeltSegmenter::mpeg7ConstQ()
+{
+	// convert to dB scale
+	for (int i = 0; i < features.size(); i++)
+		for (int j = 0; j < ncoeff; j++)
+			features[i][j] = 10.0 * log10(features[i][j] + DBL_EPSILON);
+	
+	// normalise features and add the norm at the end as an extra feature dimension
+	double maxnorm = 0;		// track the max of the norms
+	for (int i = 0; i < features.size(); i++)
+	{
+		double norm = 0;
+		for (int j = 0; j < ncoeff; j++)
+			norm += features[i][j] * features[i][j];
+		norm = sqrt(norm);
+		for (int j = 0; j < ncoeff; j++)
+			features[i][j] /= norm;
+		features[i].push_back(norm);
+		if (norm > maxnorm)
+			maxnorm = norm;
+	}
+	
+	// normalise the norms
+	for (int i = 0; i < features.size(); i++)
+		features[i][ncoeff] /= maxnorm;
+}
+*/