source: src/pitch/pitchyinfft.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: 6.4 KB
Line 
1/*
2  Copyright (C) 2003-2013 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#include "aubio_priv.h"
22#include "fvec.h"
23#include "cvec.h"
24#include "mathutils.h"
25#include "spectral/fft.h"
26#include "pitch/pitchyinfft.h"
27
28/** pitch yinfft structure */
29struct _aubio_pitchyinfft_t
30{
31  fvec_t *win;        /**< temporal weighting window */
32  fvec_t *winput;     /**< windowed spectrum */
33  fvec_t *sqrmag;     /**< square difference function */
34  fvec_t *weight;     /**< spectral weighting window (psychoacoustic model) */
35  fvec_t *fftout;     /**< Fourier transform output */
36  aubio_fft_t *fft;   /**< fft object to compute square difference function */
37  fvec_t *yinfft;     /**< Yin function */
38  smpl_t tol;         /**< Yin tolerance */
39  uint_t peak_pos;    /**< currently selected peak pos*/
40  uint_t short_period; /** shortest period under which to check for octave error */
41};
42
43static const smpl_t freqs[] = {
44     0.,    20.,    25.,   31.5,    40.,    50.,    63.,    80.,   100.,   125.,
45   160.,   200.,   250.,   315.,   400.,   500.,   630.,   800.,  1000.,  1250.,
46  1600.,  2000.,  2500.,  3150.,  4000.,  5000.,  6300.,  8000.,  9000., 10000.,
47 12500., 15000., 20000., 25100
48};
49
50static const smpl_t weight[] = {
51  -75.8,  -70.1,  -60.8,  -52.1,  -44.2,  -37.5,  -31.3,  -25.6,  -20.9,  -16.5,
52  -12.6,  -9.60,  -7.00,  -4.70,  -3.00,  -1.80,  -0.80,  -0.20,  -0.00,   0.50,
53   1.60,   3.20,   5.40,   7.80,   8.10,   5.30,  -2.40,  -11.1,  -12.8,  -12.2,
54  -7.40,  -17.8,  -17.8,  -17.8
55};
56
57aubio_pitchyinfft_t *
58new_aubio_pitchyinfft (uint_t samplerate, uint_t bufsize)
59{
60  uint_t i = 0, j = 1;
61  smpl_t freq = 0, a0 = 0, a1 = 0, f0 = 0, f1 = 0;
62  aubio_pitchyinfft_t *p = AUBIO_NEW (aubio_pitchyinfft_t);
63  p->winput = new_fvec (bufsize);
64  p->fft = new_aubio_fft (bufsize);
65  if (!p->fft) goto beach;
66  p->fftout = new_fvec (bufsize);
67  p->sqrmag = new_fvec (bufsize);
68  p->yinfft = new_fvec (bufsize / 2 + 1);
69  p->tol = 0.85;
70  p->peak_pos = 0;
71  p->win = new_aubio_window ("hanningz", bufsize);
72  p->weight = new_fvec (bufsize / 2 + 1);
73  for (i = 0; i < p->weight->length; i++) {
74    freq = (smpl_t) i / (smpl_t) bufsize *(smpl_t) samplerate;
75    while (freq > freqs[j]) {
76      j += 1;
77    }
78    a0 = weight[j - 1];
79    f0 = freqs[j - 1];
80    a1 = weight[j];
81    f1 = freqs[j];
82    if (f0 == f1) {           // just in case
83      p->weight->data[i] = a0;
84    } else if (f0 == 0) {     // y = ax+b
85      p->weight->data[i] = (a1 - a0) / f1 * freq + a0;
86    } else {
87      p->weight->data[i] = (a1 - a0) / (f1 - f0) * freq +
88          (a0 - (a1 - a0) / (f1 / f0 - 1.));
89    }
90    while (freq > freqs[j]) {
91      j += 1;
92    }
93    //AUBIO_DBG("%f\n",p->weight->data[i]);
94    p->weight->data[i] = DB2LIN (p->weight->data[i]);
95    //p->weight->data[i] = SQRT(DB2LIN(p->weight->data[i]));
96  }
97  // check for octave errors above 1300 Hz
98  p->short_period = (uint_t)ROUND(samplerate / 1300.);
99  return p;
100
101beach:
102  if (p->winput) del_fvec(p->winput);
103  AUBIO_FREE(p);
104  return NULL;
105}
106
107void
108aubio_pitchyinfft_do (aubio_pitchyinfft_t * p, const fvec_t * input, fvec_t * output)
109{
110  uint_t tau, l;
111  uint_t length = p->fftout->length;
112  uint_t halfperiod;
113  fvec_t *fftout = p->fftout;
114  fvec_t *yin = p->yinfft;
115  smpl_t tmp = 0., sum = 0.;
116  // window the input
117  fvec_weighted_copy(input, p->win, p->winput);
118  // get the real / imag parts of its fft
119  aubio_fft_do_complex (p->fft, p->winput, fftout);
120  // get the squared magnitude spectrum, applying some weight
121  p->sqrmag->data[0] = SQR(fftout->data[0]);
122  p->sqrmag->data[0] *= p->weight->data[0];
123  for (l = 1; l < length / 2; l++) {
124    p->sqrmag->data[l] = SQR(fftout->data[l]) + SQR(fftout->data[length - l]);
125    p->sqrmag->data[l] *= p->weight->data[l];
126    p->sqrmag->data[length - l] = p->sqrmag->data[l];
127  }
128  p->sqrmag->data[length / 2] = SQR(fftout->data[length / 2]);
129  p->sqrmag->data[length / 2] *= p->weight->data[length / 2];
130  // get sum of weighted squared mags
131  for (l = 0; l < length / 2 + 1; l++) {
132    sum += p->sqrmag->data[l];
133  }
134  sum *= 2.;
135  // get the real / imag parts of the fft of the squared magnitude
136  aubio_fft_do_complex (p->fft, p->sqrmag, fftout);
137  yin->data[0] = 1.;
138  for (tau = 1; tau < yin->length; tau++) {
139    // compute the square differences
140    yin->data[tau] = sum - fftout->data[tau];
141    // and the cumulative mean normalized difference function
142    tmp += yin->data[tau];
143    if (tmp != 0) {
144      yin->data[tau] *= tau / tmp;
145    } else {
146      yin->data[tau] = 1.;
147    }
148  }
149  // find best candidates
150  tau = fvec_min_elem (yin);
151  if (yin->data[tau] < p->tol) {
152    // no interpolation, directly return the period as an integer
153    //output->data[0] = tau;
154    //return;
155
156    // 3 point quadratic interpolation
157    //return fvec_quadratic_peak_pos (yin,tau,1);
158    /* additional check for (unlikely) octave doubling in higher frequencies */
159    if (tau > p->short_period) {
160      output->data[0] = fvec_quadratic_peak_pos (yin, tau);
161    } else {
162      /* should compare the minimum value of each interpolated peaks */
163      halfperiod = FLOOR (tau / 2 + .5);
164      if (yin->data[halfperiod] < p->tol)
165        p->peak_pos = halfperiod;
166      else
167        p->peak_pos = tau;
168      output->data[0] = fvec_quadratic_peak_pos (yin, p->peak_pos);
169    }
170  } else {
171    p->peak_pos = 0;
172    output->data[0] = 0.;
173  }
174}
175
176void
177del_aubio_pitchyinfft (aubio_pitchyinfft_t * p)
178{
179  del_fvec (p->win);
180  del_aubio_fft (p->fft);
181  del_fvec (p->yinfft);
182  del_fvec (p->sqrmag);
183  del_fvec (p->fftout);
184  del_fvec (p->winput);
185  del_fvec (p->weight);
186  AUBIO_FREE (p);
187}
188
189smpl_t
190aubio_pitchyinfft_get_confidence (aubio_pitchyinfft_t * o) {
191  return 1. - o->yinfft->data[o->peak_pos];
192}
193
194uint_t
195aubio_pitchyinfft_set_tolerance (aubio_pitchyinfft_t * p, smpl_t tol)
196{
197  p->tol = tol;
198  return 0;
199}
200
201smpl_t
202aubio_pitchyinfft_get_tolerance (aubio_pitchyinfft_t * p)
203{
204  return p->tol;
205}
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