libs/Music/CombedFT.h

   1 // Copyright 2004 "Gilles Degottex"
   2
   3 // This file is part of "Music"
   4
   5 // "Music" is free software; you can redistribute it and/or modify
   6 // it under the terms of the GNU Lesser General Public License as published by
   7 // the Free Software Foundation; either version 2.1 of the License, or
   8 // (at your option) any later version.
   9 //
  10 // "Music" is distributed in the hope that it will be useful,
  11 // but WITHOUT ANY WARRANTY; without even the implied warranty of
  12 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  13 // GNU Lesser General Public License for more details.
  14 //
  15 // You should have received a copy of the GNU Lesser General Public License
  16 // along with this program; if not, write to the Free Software
  17 // Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  18
  19
  20 #ifndef _CombedFT_h_
  21 #define _CombedFT_h_
  22
  23 #include <vector>
  24 #include <deque>
  25 #include <complex>
  26 using namespace std;
  27 #include <CppAddons/CAMath.h>
  28
  29 #include "Music.h"
  30 #include "CFFTW3.h"
  31 #include "Algorithm.h"
  32
  33 namespace Music
  34 {
  35         /*! Combed FT for one voice
  36          * Hypothesis: the highest energy peak takes part of the instrument sound
  37          * O(2*nln(n))
  38          */
  39         class CombedFT : public Transform
  40         {
  41                 protected:
  42                         vector<double> m_win;
  43                         CFFTW3 m_comb;
  44
  45                         double m_f0;
  46                         double m_audib_ratio;
  47                         bool m_use_audibility_treshold;
  48                         double m_zp_factor;
  49                         double m_window_factor;
  50
  51                         virtual void init();
  52                         virtual void AFreqChanged()                                                     {init();}
  53                         virtual void samplingRateChanged()                                      {init();}
  54                         virtual void semitoneBoundsChanged()                            {init();}
  55
  56                 public:
  57                         CombedFT();
  58
  59                         CFFTW3 m_plan;
  60
  61                         void setZeroPaddingFactor(double zp);
  62                         double getZeroPaddingFactor() const                                     {return m_zp_factor;}
  63
  64                         void setWindowFactor(double wf);
  65                         double getWindowFactor() const                                          {return m_window_factor;}
  66
  67                         /*! set audibility ratio of low harmonics against higher ones
  68                          * decrease influences of low harmonics in the evaluation of the fundamental.
  69                          * (avoid many too-low evaluation in high frequencies)
  70                          * Sometimes in high pitch notes (eg. G3 with bari-sax) a "disturbing" component appears
  71                          * at frequency f=G2 and so the fundamental is badly evaluated.
  72                          * By "disturbing" I mean: present in the spectral representation, but not audible or weak to much to change the impression of the pitch.
  73                          * Actually, that's a physiological setting, there is no "true" choice for a such situation.
  74                          * in [0, inf], 0 mean no correction, a good value seems to be 0.1
  75                          */
  76                         void useAudibilityRatio(bool use)                                       {m_use_audibility_treshold=use;}
  77                         void setAudibilityRatio(double audib_ratio=0.1)         {m_audib_ratio=audib_ratio;}
  78                         double getAudibilityRatio()                                                     {return m_audib_ratio;}
  79
  80                         virtual int getSampleAlgoLatency() const;
  81                         virtual double getFondamentalFreq() const;
  82                         virtual bool hasNoteRecognized() const                          {return m_f0>0.0;}
  83                         virtual int getMinSize() const;
  84                         virtual void apply(const deque<double>& buff);
  85
  86                         ~CombedFT();
  87         };
  88 }
  89
  90 #endif