Chris@35: /* -*- c-basic-offset: 4 indent-tabs-mode: nil -*-  vi:set ts=8 sts=4 sw=4: */
Chris@35: 
Chris@42: /*
Chris@42:     Tipic
Chris@42: 
Chris@42:     Centre for Digital Music, Queen Mary, University of London.
Chris@42: 
Chris@42:     This program is free software; you can redistribute it and/or
Chris@42:     modify it under the terms of the GNU General Public License as
Chris@42:     published by the Free Software Foundation; either version 2 of the
Chris@42:     License, or (at your option) any later version.  See the file
Chris@42:     COPYING included with this distribution for more information.
Chris@42: */
Chris@42: 
Chris@35: #ifndef FEATURE_DOWNSAMPLE_H
Chris@35: #define FEATURE_DOWNSAMPLE_H
Chris@35: 
Chris@35: #include <vector>
Chris@35: 
Chris@35: #include "Types.h"
Chris@35: 
Chris@57: /**
Chris@57:  * Downsample a feature by a factor in time.
Chris@57:  *
Chris@57:  * This class retains internal history, so a single instance per
Chris@57:  * channel or feature type is required. It is also not thread-safe.
Chris@57:  */
Chris@35: class Filter;
Chris@35: 
Chris@35: class FeatureDownsample
Chris@35: {
Chris@35: public:
Chris@35:     struct Parameters {
Chris@35: 	int featureSize;
Chris@35: 	int downsampleFactor;
Chris@35: 	int windowLength;
Chris@37:         int normP; // 0 = no normalisation, 1 = L^1, 2 = L^2
Chris@37:         double normThresh;
Chris@35: 	Parameters() :
Chris@35: 	    featureSize(1),
Chris@35: 	    downsampleFactor(10),
Chris@37: 	    windowLength(41),
Chris@37: 	    normP(2),
Chris@37: 	    normThresh(1e-6)
Chris@35: 	{ }
Chris@35:     };
Chris@35: 
Chris@35:     FeatureDownsample(Parameters params);
Chris@35:     ~FeatureDownsample();
Chris@35: 
Chris@35:     void reset();
Chris@35:     RealBlock process(const RealBlock &in);
Chris@36:     RealBlock getRemainingOutput();
Chris@35:     
Chris@35: private:
Chris@35:     Parameters m_params;
Chris@35:     std::vector<Filter *> m_filters;
Chris@36:     int m_toDrop;
Chris@35:     int m_toNext;
Chris@36:     int m_inCount;
Chris@36:     int m_outCount;
Chris@35: };
Chris@35: 
Chris@35: #endif