source: src/pitch/pitchyin.c @ 3e48568

feature/autosinkfeature/constantqfeature/pitchshiftfeature/pydocstringsfeature/timestretch
Last change on this file since 3e48568 was 3e48568, checked in by Eduard Müller <mueller.eduard@googlemail.com>, 3 years ago

yin pitch confidence tweaks

return pitch candidate search's confidence in yin algorithms and not the
global minimum, so that the confidence reflects the returned pitch value

  • Property mode set to 100644
File size: 4.3 KB
Line 
1/*
2  Copyright (C) 2003-2009 Paul Brossier <piem@aubio.org>
3
4  This file is part of aubio.
5
6  aubio is free software: you can redistribute it and/or modify
7  it under the terms of the GNU General Public License as published by
8  the Free Software Foundation, either version 3 of the License, or
9  (at your option) any later version.
10
11  aubio is distributed in the hope that it will be useful,
12  but WITHOUT ANY WARRANTY; without even the implied warranty of
13  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
14  GNU General Public License for more details.
15
16  You should have received a copy of the GNU General Public License
17  along with aubio.  If not, see <http://www.gnu.org/licenses/>.
18
19*/
20
21/* This algorithm was developed by A. de Cheveigné and H. Kawahara and
22 * published in:
23 *
24 * de Cheveigné, A., Kawahara, H. (2002) "YIN, a fundamental frequency
25 * estimator for speech and music", J. Acoust. Soc. Am. 111, 1917-1930. 
26 *
27 * see http://recherche.ircam.fr/equipes/pcm/pub/people/cheveign.html
28 */
29
30#include "aubio_priv.h"
31#include "fvec.h"
32#include "mathutils.h"
33#include "pitch/pitchyin.h"
34
35struct _aubio_pitchyin_t
36{
37  fvec_t *yin;
38  smpl_t tol;
39  uint_t peak_pos;
40};
41
42/** compute difference function
43
44  \param input input signal
45  \param yinbuf output buffer to store difference function (half shorter than input)
46
47*/
48void aubio_pitchyin_diff (fvec_t * input, fvec_t * yinbuf);
49
50/** in place computation of the YIN cumulative normalised function
51
52  \param yinbuf input signal (a square difference function), also used to store function
53
54*/
55void aubio_pitchyin_getcum (fvec_t * yinbuf);
56
57/** detect pitch in a YIN function
58
59  \param yinbuf input buffer as computed by aubio_pitchyin_getcum
60
61*/
62uint_t aubio_pitchyin_getpitch (const fvec_t * yinbuf);
63
64aubio_pitchyin_t *
65new_aubio_pitchyin (uint_t bufsize)
66{
67  aubio_pitchyin_t *o = AUBIO_NEW (aubio_pitchyin_t);
68  o->yin = new_fvec (bufsize / 2);
69  o->tol = 0.15;
70  o->peak_pos = 0;
71  return o;
72}
73
74void
75del_aubio_pitchyin (aubio_pitchyin_t * o)
76{
77  del_fvec (o->yin);
78  AUBIO_FREE (o);
79}
80
81/* outputs the difference function */
82void
83aubio_pitchyin_diff (fvec_t * input, fvec_t * yin)
84{
85  uint_t j, tau;
86  smpl_t tmp;
87  for (tau = 0; tau < yin->length; tau++) {
88    yin->data[tau] = 0.;
89  }
90  for (tau = 1; tau < yin->length; tau++) {
91    for (j = 0; j < yin->length; j++) {
92      tmp = input->data[j] - input->data[j + tau];
93      yin->data[tau] += SQR (tmp);
94    }
95  }
96}
97
98/* cumulative mean normalized difference function */
99void
100aubio_pitchyin_getcum (fvec_t * yin)
101{
102  uint_t tau;
103  smpl_t tmp = 0.;
104  yin->data[0] = 1.;
105  //AUBIO_DBG("%f\t",yin->data[0]);
106  for (tau = 1; tau < yin->length; tau++) {
107    tmp += yin->data[tau];
108    yin->data[tau] *= tau / tmp;
109    //AUBIO_DBG("%f\t",yin->data[tau]);
110  }
111  //AUBIO_DBG("\n");
112}
113
114uint_t
115aubio_pitchyin_getpitch (const fvec_t * yin)
116{
117  uint_t tau = 1;
118  do {
119    if (yin->data[tau] < 0.1) {
120      while (yin->data[tau + 1] < yin->data[tau]) {
121        tau++;
122      }
123      return tau;
124    }
125    tau++;
126  } while (tau < yin->length);
127  //AUBIO_DBG("No pitch found");
128  return 0;
129}
130
131/* all the above in one */
132void
133aubio_pitchyin_do (aubio_pitchyin_t * o, const fvec_t * input, fvec_t * out)
134{
135  const smpl_t tol = o->tol;
136  fvec_t* yin = o->yin;
137  const smpl_t *input_data = input->data;
138  const uint_t length = yin->length;
139  smpl_t *yin_data = yin->data;
140  uint_t j, tau;
141  sint_t period;
142  smpl_t tmp, tmp2 = 0.;
143
144  yin_data[0] = 1.;
145  for (tau = 1; tau < length; tau++) {
146    yin_data[tau] = 0.;
147    for (j = 0; j < length; j++) {
148      tmp = input_data[j] - input_data[j + tau];
149      yin_data[tau] += SQR (tmp);
150    }
151    tmp2 += yin_data[tau];
152    if (tmp2 != 0) {
153      yin->data[tau] *= tau / tmp2;
154    } else {
155      yin->data[tau] = 1.;
156    }
157    period = tau - 3;
158    if (tau > 4 && (yin_data[period] < tol) &&
159        (yin_data[period] < yin_data[period + 1])) {
160      o->peak_pos = (uint_t)period;
161      out->data[0] = fvec_quadratic_peak_pos (yin, o->peak_pos);
162      return;
163    }
164  }
165  o->peak_pos = (uint_t)fvec_min_elem (yin);
166  out->data[0] = fvec_quadratic_peak_pos (yin, o->peak_pos);
167}
168
169smpl_t
170aubio_pitchyin_get_confidence (aubio_pitchyin_t * o) {
171  return 1. - o->yin->data[o->peak_pos];
172}
173
174uint_t
175aubio_pitchyin_set_tolerance (aubio_pitchyin_t * o, smpl_t tol)
176{
177  o->tol = tol;
178  return 0;
179}
180
181smpl_t
182aubio_pitchyin_get_tolerance (aubio_pitchyin_t * o)
183{
184  return o->tol;
185}
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