src/pitchyin.c

   1 /*
   2    Copyright (C) 2003 Paul Brossier
   3
   4    This program is free software; you can redistribute it and/or modify
   5    it under the terms of the GNU General Public License as published by
   6    the Free Software Foundation; either version 2 of the License, or
   7    (at your option) any later version.
   8
   9    This program is distributed in the hope that it will be useful,
  10    but WITHOUT ANY WARRANTY; without even the implied warranty of
  11    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12    GNU General Public License for more details.
  13
  14    You should have received a copy of the GNU General Public License
  15    along with this program; if not, write to the Free Software
  16    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  17 */
  18
  19 /* This algorithm was developped by A. de Cheveigne and H. Kawahara and
  20  * published in:
  21  *
  22  * de Cheveigné, A., Kawahara, H. (2002) "YIN, a fundamental frequency
  23  * estimator for speech and music", J. Acoust. Soc. Am. 111, 1917-1930.
  24  *
  25  * see http://recherche.ircam.fr/equipes/pcm/pub/people/cheveign.html
  26  */
  27
  28 #include "aubio_priv.h"
  29 #include "sample.h"
  30 #include "mathutils.h"
  31 #include "pitchyin.h"
  32
  33 /* outputs the difference function */
  34 void aubio_pitchyin_diff(fvec_t * input, fvec_t * yin){
  35         uint_t c,j,tau;
  36         smpl_t tmp;
  37         for (c=0;c<input->channels;c++)
  38         {
  39                 for (tau=0;tau<yin->length;tau++)
  40                 {
  41                         yin->data[c][tau] = 0.;
  42                 }
  43                 for (tau=1;tau<yin->length;tau++)
  44                 {
  45                         for (j=0;j<yin->length;j++)
  46                         {
  47                                 tmp = input->data[c][j] - input->data[c][j+tau];
  48                                 yin->data[c][tau] += SQR(tmp);
  49                         }
  50                 }
  51         }
  52 }
  53
  54 /* cumulative mean normalized difference function */
  55 void aubio_pitchyin_getcum(fvec_t * yin) {
  56         uint_t c,tau;
  57         smpl_t tmp;
  58         for (c=0;c<yin->channels;c++)
  59         {
  60                 tmp = 0.;
  61                 yin->data[c][0] = 1.;
  62                 //AUBIO_DBG("%f\t",yin->data[c][0]);
  63                 for (tau=1;tau<yin->length;tau++)
  64                 {
  65                         tmp += yin->data[c][tau];
  66                         yin->data[c][tau] *= tau/tmp;
  67                         //AUBIO_DBG("%f\t",yin->data[c][tau]);
  68                 }
  69                 //AUBIO_DBG("\n");
  70         }
  71 }
  72
  73 uint_t aubio_pitchyin_getpitch(fvec_t * yin) {
  74         uint_t c=0,tau=1;
  75         do
  76         {
  77                 if(yin->data[c][tau] < 0.1) {
  78                         while (yin->data[c][tau+1] < yin->data[c][tau]) {
  79                                 tau++;
  80                         }
  81                         return tau;
  82                 }
  83                 tau++;
  84         } while (tau<yin->length);
  85         //AUBIO_DBG("No pitch found");
  86         return 0;
  87 }
  88
  89
  90 /* all the above in one */
  91 void aubio_pitchyin_getpitchfast(fvec_t * input, fvec_t * yin){
  92         uint_t c,j,tau;
  93         smpl_t tmp, tmp2;
  94         for (c=0;c<input->channels;c++)
  95         {
  96                 for (tau=0;tau<yin->length;tau++)
  97                 {
  98                         yin->data[c][tau] = 0.;
  99                 }
 100                 for (tau=1;tau<yin->length;tau++)
 101                 {
 102                         for (j=0;j<yin->length;j++)
 103                         {
 104                                 tmp = input->data[c][j] - input->data[c][j+tau];
 105                                 yin->data[c][tau] += SQR(tmp);
 106                         }
 107                 }
 108                 tmp2 = 0.;
 109                 yin->data[c][0] = 1.;
 110                 for (tau=1;tau<yin->length;tau++)
 111                 {
 112                         tmp += yin->data[c][tau];
 113                         yin->data[c][tau] *= tau/tmp;
 114                 }
 115         }
 116         /* should merge the following with above */
 117         do
 118         {
 119                 if(yin->data[c][tau] < 0.1) {
 120                         while (yin->data[c][tau+1] < yin->data[c][tau]) {
 121                                 tau++;
 122                         }
 123                         return tau;
 124                 }
 125                 tau++;
 126         } while (tau<yin->length);
 127         return 0;
 128 }
 129