Chris@4: /* -*- c-basic-offset: 4 indent-tabs-mode: nil -*-  vi:set ts=8 sts=4 sw=4: */
Chris@4: 
Chris@4: /*
Chris@4:   Vamp feature extraction plugin for the BeatRoot beat tracker.
Chris@4: 
Chris@4:   Centre for Digital Music, Queen Mary, University of London.
Chris@4:   This file copyright 2011 Simon Dixon, Chris Cannam and QMUL.
Chris@4:     
Chris@4:   This program is free software; you can redistribute it and/or
Chris@4:   modify it under the terms of the GNU General Public License as
Chris@4:   published by the Free Software Foundation; either version 2 of the
Chris@4:   License, or (at your option) any later version.  See the file
Chris@4:   COPYING included with this distribution for more information.
Chris@4: */
Chris@4: 
Chris@4: #ifndef _BEATROOT_PEAKS_H_
Chris@4: #define _BEATROOT_PEAKS_H_
Chris@4: 
Chris@4: #include <vector>
Chris@4: #include <cmath>
Chris@4: 
Chris@4: using std::vector;
Chris@4: 
Chris@4: class Peaks
Chris@4: {
Chris@4: protected:
Chris@4:     static int pre;
Chris@4:     static int post;
Chris@4: 	
Chris@4: public:
Chris@4:     /** General peak picking method for finding n local maxima in an array
Chris@4:      *  @param data input data
Chris@4:      *  @param peaks list of peak indexes
Chris@4:      *  @param width minimum distance between peaks
Chris@4:      */
Chris@15:     static int findPeaks(const vector<double> &data, vector<int> peaks, int width);
Chris@4: 
Chris@4:     /** General peak picking method for finding local maxima in an array
Chris@4:      *  @param data input data
Chris@4:      *  @param width minimum distance between peaks
Chris@4:      *  @param threshold minimum value of peaks
Chris@4:      *  @return list of peak indexes
Chris@4:      */ 
Chris@4:     static vector<int> findPeaks(const vector<double> &data, int width,
Chris@4: 				 double threshold) {
Chris@4: 	return findPeaks(data, width, threshold, 0, false);
Chris@4:     } // findPeaks()
Chris@4: 	
Chris@4:     /** General peak picking method for finding local maxima in an array
Chris@4:      *  @param data input data
Chris@4:      *  @param width minimum distance between peaks
Chris@4:      *  @param threshold minimum value of peaks
Chris@4:      *  @param decayRate how quickly previous peaks are forgotten
Chris@4:      *  @param isRelative minimum value of peaks is relative to local average
Chris@4:      *  @return list of peak indexes
Chris@4:      */
Chris@4:     static vector<int> findPeaks(const vector<double> &data, int width,
Chris@15: 				 double threshold, double decayRate, bool isRelative);
Chris@4: 
Chris@4:     static double expDecayWithHold(double av, double decayRate,
Chris@15: 				   const vector<double> &data, int start, int stop);
Chris@4: 
Chris@4:     static bool overThreshold(const vector<double> &data, int index, int width,
Chris@15:                               double threshold, bool isRelative,
Chris@15:                               double av);
Chris@4: 
Chris@15:     static void normalise(vector<double> &data);
Chris@4: 
Chris@4:     /** Uses an n-point linear regression to estimate the slope of data.
Chris@4:      *  @param data input data
Chris@4:      *  @param hop spacing of data points
Chris@4:      *  @param n length of linear regression
Chris@4:      *  @param slope output data
Chris@4:      */
Chris@4:     static void getSlope(const vector<double> &data, double hop, int n,
Chris@15: 			 vector<double> &slope);
Chris@4: 
Chris@18:     static double min(const vector<double> &arr) {
Chris@18:         if (arr.empty()) return 0;
Chris@18:         return arr[imin(arr)];
Chris@18:     }
Chris@18:     static double max(const vector<double> &arr) {
Chris@18:         if (arr.empty()) return 0;
Chris@18:         return arr[imax(arr)];
Chris@18:     }
Chris@4: 
Chris@15:     static int imin(const vector<double> &arr);
Chris@15:     static int imax(const vector<double> &arr);
Chris@4: 
Chris@4: }; // class Peaks
Chris@4: 
Chris@4: #endif