source: src/onset/peakpicker.c @ 5d16185

feature/autosinkfeature/cnnfeature/cnn_orgfeature/constantqfeature/crepefeature/crepe_orgfeature/pitchshiftfeature/pydocstringsfeature/timestretchfix/ffmpeg5pitchshiftsamplertimestretchyinfft+
Last change on this file since 5d16185 was 0b9a02a, checked in by Paul Brossier <piem@piem.org>, 15 years ago

src/onset: mono

  • Property mode set to 100644
File size: 6.0 KB
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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#include "aubio_priv.h"
22#include "fvec.h"
23#include "mathutils.h"
24#include "lvec.h"
25#include "temporal/filter.h"
26#include "temporal/biquad.h"
27#include "onset/peakpicker.h"
28
29/** function pointer to thresholding function */
30typedef smpl_t (*aubio_thresholdfn_t)(fvec_t *input);
31/** function pointer to peak-picking function */
32typedef uint_t (*aubio_pickerfn_t)(fvec_t *input, uint_t pos);
33
34/** set peak picker thresholding function */
35uint_t aubio_peakpicker_set_thresholdfn(aubio_peakpicker_t * p, aubio_thresholdfn_t thresholdfn);
36/** get peak picker thresholding function */
37aubio_thresholdfn_t aubio_peakpicker_get_thresholdfn(aubio_peakpicker_t * p);
38
39/* peak picking parameters, default values in brackets
40 *
41 *     [<----post----|--pre-->]
42 *  .................|.............
43 *  time->           ^now
44 */
45struct _aubio_peakpicker_t
46{
47        /** thresh: offset threshold [0.033 or 0.01] */
48  smpl_t threshold;
49        /** win_post: median filter window length (causal part) [8] */
50  uint_t win_post;
51        /** pre: median filter window (anti-causal part) [post-1] */
52  uint_t win_pre;
53        /** threshfn: name or handle of fn for computing adaptive threshold [median]  */
54  aubio_thresholdfn_t thresholdfn;
55        /** picker: name or handle of fn for picking event times [peakpick] */
56  aubio_pickerfn_t pickerfn;
57
58        /** biquad lowpass filter */
59  aubio_filter_t *biquad;
60        /** original onsets */
61  fvec_t *onset_keep;
62        /** modified onsets */
63  fvec_t *onset_proc;
64        /** peak picked window [3] */
65  fvec_t *onset_peek;
66        /** thresholded function */
67  fvec_t *thresholded;
68        /** scratch pad for biquad and median */
69  fvec_t *scratch;
70
71        /** \bug should be used to calculate filter coefficients */
72  /* cutoff: low-pass filter cutoff [0.34, 1] */
73  /* smpl_t cutoff; */
74
75  /* not used anymore */
76  /* time precision [512/44100  winlength/samplerate, fs/buffer_size */
77  /* smpl_t tau; */
78  /* alpha: normalisation exponent [9] */
79  /* smpl_t alpha; */
80};
81
82
83/** modified version for real time, moving mean adaptive threshold this method
84 * is slightly more permissive than the offline one, and yelds to an increase
85 * of false positives. best  */
86void
87aubio_peakpicker_do (aubio_peakpicker_t * p, fvec_t * onset, fvec_t * out)
88{
89  fvec_t *onset_keep = p->onset_keep;
90  fvec_t *onset_proc = p->onset_proc;
91  fvec_t *onset_peek = p->onset_peek;
92  fvec_t *thresholded = p->thresholded;
93  fvec_t *scratch = p->scratch;
94  smpl_t mean = 0., median = 0.;
95  uint_t length = p->win_post + p->win_pre + 1;
96  uint_t j = 0;
97
98  /* store onset in onset_keep */
99  /* shift all elements but last, then write last */
100  for (j = 0; j < length - 1; j++) {
101    onset_keep->data[j] = onset_keep->data[j + 1];
102    onset_proc->data[j] = onset_keep->data[j];
103  }
104  onset_keep->data[length - 1] = onset->data[0];
105  onset_proc->data[length - 1] = onset->data[0];
106
107  /* filter onset_proc */
108  /** \bug filtfilt calculated post+pre times, should be only once !? */
109  aubio_filter_do_filtfilt (p->biquad, onset_proc, scratch);
110
111  /* calculate mean and median for onset_proc */
112  mean = fvec_mean (onset_proc);
113  /* copy to scratch */
114  for (j = 0; j < length; j++)
115    scratch->data[j] = onset_proc->data[j];
116  median = p->thresholdfn (scratch);
117
118  /* shift peek array */
119  for (j = 0; j < 3 - 1; j++)
120    onset_peek->data[j] = onset_peek->data[j + 1];
121  /* calculate new tresholded value */
122  thresholded->data[0] =
123      onset_proc->data[p->win_post] - median - mean * p->threshold;
124  onset_peek->data[2] = thresholded->data[0];
125  out->data[0] = (p->pickerfn) (onset_peek, 1);
126  if (out->data[0]) {
127    out->data[0] = fvec_quadint (onset_peek, 1);
128  }
129}
130
131/** this method returns the current value in the pick peaking buffer
132 * after smoothing
133 */
134fvec_t *
135aubio_peakpicker_get_thresholded_input (aubio_peakpicker_t * p)
136{
137  return p->thresholded;
138}
139
140uint_t
141aubio_peakpicker_set_threshold (aubio_peakpicker_t * p, smpl_t threshold)
142{
143  p->threshold = threshold;
144  return AUBIO_OK;
145}
146
147smpl_t
148aubio_peakpicker_get_threshold (aubio_peakpicker_t * p)
149{
150  return p->threshold;
151}
152
153uint_t
154aubio_peakpicker_set_thresholdfn (aubio_peakpicker_t * p,
155    aubio_thresholdfn_t thresholdfn)
156{
157  p->thresholdfn = thresholdfn;
158  return AUBIO_OK;
159}
160
161aubio_thresholdfn_t
162aubio_peakpicker_get_thresholdfn (aubio_peakpicker_t * p)
163{
164  return (aubio_thresholdfn_t) (p->thresholdfn);
165}
166
167aubio_peakpicker_t *
168new_aubio_peakpicker ()
169{
170  aubio_peakpicker_t *t = AUBIO_NEW (aubio_peakpicker_t);
171  t->threshold = 0.1;           /* 0.0668; 0.33; 0.082; 0.033; */
172  t->win_post = 5;
173  t->win_pre = 1;
174
175  t->thresholdfn = (aubio_thresholdfn_t) (fvec_median); /* (fvec_mean); */
176  t->pickerfn = (aubio_pickerfn_t) (fvec_peakpick);
177
178  t->scratch = new_fvec (t->win_post + t->win_pre + 1);
179  t->onset_keep = new_fvec (t->win_post + t->win_pre + 1);
180  t->onset_proc = new_fvec (t->win_post + t->win_pre + 1);
181  t->onset_peek = new_fvec (3);
182  t->thresholded = new_fvec (1);
183
184  /* cutoff: low-pass filter with cutoff reduced frequency at 0.34
185     generated with octave butter function: [b,a] = butter(2, 0.34);
186   */
187  t->biquad = new_aubio_filter_biquad (0.15998789, 0.31997577, 0.15998789,
188      -0.59488894, 0.23484048);
189
190  return t;
191}
192
193void
194del_aubio_peakpicker (aubio_peakpicker_t * p)
195{
196  del_aubio_filter (p->biquad);
197  del_fvec (p->onset_keep);
198  del_fvec (p->onset_proc);
199  del_fvec (p->onset_peek);
200  del_fvec (p->thresholded);
201  del_fvec (p->scratch);
202  AUBIO_FREE (p);
203}
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