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 #ifndef QM_DSP_TEMPOTRACKV2_H 17 #define QM_DSP_TEMPOTRACKV2_H 18 19 #include <vector> 20 21 //!!! Question: how far is this actually sample rate dependent? I 22 // think it does produce plausible results for e.g. 48000 as well as 23 // 44100, but surely the fixed window sizes and comb filtering will 24 // make it prefer double or half time when run at e.g. 96000? 25 26 class TempoTrackV2 27 { 28 public: 29 /** 30 * Construct a tempo tracker that will operate on beat detection 31 * function data calculated from audio at the given sample rate 32 * with the given frame increment. 33 * 34 * Currently the sample rate and increment are used only for the 35 * conversion from beat frame location to bpm in the tempo array. 36 */ 37 TempoTrackV2(float sampleRate, int dfIncrement); 38 ~TempoTrackV2(); 39 40 // Returned beat periods are given in df increment units; inputtempo and tempi in bpm calculateBeatPeriod(const std::vector<double> & df,std::vector<double> & beatPeriod,std::vector<double> & tempi)41 void calculateBeatPeriod(const std::vector<double> &df, 42 std::vector<double> &beatPeriod, 43 std::vector<double> &tempi) { 44 calculateBeatPeriod(df, beatPeriod, tempi, 120.0, false); 45 } 46 47 // Returned beat periods are given in df increment units; inputtempo and tempi in bpm 48 // MEPD 28/11/12 Expose inputtempo and constraintempo parameters 49 // Note, if inputtempo = 120 and constraintempo = false, then functionality is as it was before 50 void calculateBeatPeriod(const std::vector<double> &df, 51 std::vector<double> &beatPeriod, 52 std::vector<double> &tempi, 53 double inputtempo, bool constraintempo); 54 55 // Returned beat positions are given in df increment units calculateBeats(const std::vector<double> & df,const std::vector<double> & beatPeriod,std::vector<double> & beats)56 void calculateBeats(const std::vector<double> &df, 57 const std::vector<double> &beatPeriod, 58 std::vector<double> &beats) { 59 calculateBeats(df, beatPeriod, beats, 0.9, 4.0); 60 } 61 62 // Returned beat positions are given in df increment units 63 // MEPD 28/11/12 Expose alpha and tightness parameters 64 // Note, if alpha = 0.9 and tightness = 4, then functionality is as it was before 65 void calculateBeats(const std::vector<double> &df, 66 const std::vector<double> &beatPeriod, 67 std::vector<double> &beats, 68 double alpha, double tightness); 69 70 private: 71 typedef std::vector<int> i_vec_t; 72 typedef std::vector<std::vector<int> > i_mat_t; 73 typedef std::vector<double> d_vec_t; 74 typedef std::vector<std::vector<double> > d_mat_t; 75 76 float m_rate; 77 int m_increment; 78 79 void adapt_thresh(d_vec_t &df); 80 double mean_array(const d_vec_t &dfin, int start, int end); 81 void filter_df(d_vec_t &df); 82 void get_rcf(const d_vec_t &dfframe, const d_vec_t &wv, d_vec_t &rcf); 83 void viterbi_decode(const d_mat_t &rcfmat, const d_vec_t &wv, 84 d_vec_t &bp, d_vec_t &tempi); 85 double get_max_val(const d_vec_t &df); 86 int get_max_ind(const d_vec_t &df); 87 void normalise_vec(d_vec_t &df); 88 }; 89 90 #endif 91