1 /* -*- c-basic-offset: 4 indent-tabs-mode: nil -*- vi:set ts=8 sts=4 sw=4: */ 2 3 /* 4 QM DSP Library 5 6 Centre for Digital Music, Queen Mary, University of London. 7 This file copyright 2008-2009 Matthew Davies and QMUL. 8 9 This program is free software; you can redistribute it and/or 10 modify it under the terms of the GNU General Public License as 11 published by the Free Software Foundation; either version 2 of the 12 License, or (at your option) any later version. See the file 13 COPYING included with this distribution for more information. 14 */ 15 16 17 #ifndef TEMPOTRACKV2_H 18 #define TEMPOTRACKV2_H 19 20 #include <vector> 21 using namespace std; 22 23 //!!! Question: how far is this actually sample rate dependent? I 24 // think it does produce plausible results for e.g. 48000 as well as 25 // 44100, but surely the fixed window sizes and comb filtering will 26 // make it prefer double or half time when run at e.g. 96000? 27 28 class TempoTrackV2 29 { 30 public: 31 /** 32 * Construct a tempo tracker that will operate on beat detection 33 * function data calculated from audio at the given sample rate 34 * with the given frame increment. 35 * 36 * Currently the sample rate and increment are used only for the 37 * conversion from beat frame location to bpm in the tempo array. 38 */ 39 TempoTrackV2(float sampleRate, size_t dfIncrement); 40 ~TempoTrackV2(); 41 42 // Returned beat periods are given in df increment units; inputtempo and tempi in bpm calculateBeatPeriod(const vector<double> & df,vector<double> & beatPeriod,vector<double> & tempi)43 void calculateBeatPeriod(const vector<double> &df, 44 vector<double> &beatPeriod, 45 vector<double> &tempi) { 46 calculateBeatPeriod(df, beatPeriod, tempi, 120.0, false); 47 } 48 49 // Returned beat periods are given in df increment units; inputtempo and tempi in bpm 50 // MEPD 28/11/12 Expose inputtempo and constraintempo parameters 51 // Note, if inputtempo = 120 and constraintempo = false, then functionality is as it was before 52 void calculateBeatPeriod(const vector<double> &df, 53 vector<double> &beatPeriod, 54 vector<double> &tempi, 55 double inputtempo, bool constraintempo); 56 57 // Returned beat positions are given in df increment units calculateBeats(const vector<double> & df,const vector<double> & beatPeriod,vector<double> & beats)58 void calculateBeats(const vector<double> &df, 59 const vector<double> &beatPeriod, 60 vector<double> &beats) { 61 calculateBeats(df, beatPeriod, beats, 0.9, 4.0); 62 } 63 64 // Returned beat positions are given in df increment units 65 // MEPD 28/11/12 Expose alpha and tightness parameters 66 // Note, if alpha = 0.9 and tightness = 4, then functionality is as it was before 67 void calculateBeats(const vector<double> &df, 68 const vector<double> &beatPeriod, 69 vector<double> &beats, 70 double alpha, double tightness); 71 72 private: 73 typedef vector<int> i_vec_t; 74 typedef vector<vector<int> > i_mat_t; 75 typedef vector<double> d_vec_t; 76 typedef vector<vector<double> > d_mat_t; 77 78 float m_rate; 79 size_t m_increment; 80 81 void adapt_thresh(d_vec_t &df); 82 double mean_array(const d_vec_t &dfin, int start, int end); 83 void filter_df(d_vec_t &df); 84 void get_rcf(const d_vec_t &dfframe, const d_vec_t &wv, d_vec_t &rcf); 85 void viterbi_decode(const d_mat_t &rcfmat, const d_vec_t &wv, 86 d_vec_t &bp, d_vec_t &tempi); 87 double get_max_val(const d_vec_t &df); 88 int get_max_ind(const d_vec_t &df); 89 void normalise_vec(d_vec_t &df); 90 }; 91 92 #endif 93