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 */
30 typedef smpl_t (*aubio_thresholdfn_t)(fvec_t *input);
31 /** function pointer to peak-picking function */
32 typedef uint_t (*aubio_pickerfn_t)(fvec_t *input, uint_t pos);
33
34 /** set peak picker thresholding function */
35 uint_t aubio_peakpicker_set_thresholdfn(aubio_peakpicker_t * p, aubio_thresholdfn_t thresholdfn);
36 /** get peak picker thresholding function */
37 aubio_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 */
45 struct _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 */
86 void
aubio_peakpicker_do(aubio_peakpicker_t * p,fvec_t * onset,fvec_t * out)87 aubio_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 j = 0;
96
97 /* push new novelty to the end */
98 fvec_push(onset_keep, onset->data[0]);
99 /* store a copy */
100 fvec_copy(onset_keep, onset_proc);
101
102 /* filter this copy */
103 aubio_filter_do_filtfilt (p->biquad, onset_proc, scratch);
104
105 /* calculate mean and median for onset_proc */
106 mean = fvec_mean (onset_proc);
107
108 /* copy to scratch and compute its median */
109 fvec_copy(onset_proc, scratch);
110 median = p->thresholdfn (scratch);
111
112 /* shift peek array */
113 for (j = 0; j < 3 - 1; j++)
114 onset_peek->data[j] = onset_peek->data[j + 1];
115 /* calculate new tresholded value */
116 thresholded->data[0] =
117 onset_proc->data[p->win_post] - median - mean * p->threshold;
118 onset_peek->data[2] = thresholded->data[0];
119 out->data[0] = (p->pickerfn) (onset_peek, 1);
120 if (out->data[0]) {
121 out->data[0] = fvec_quadratic_peak_pos (onset_peek, 1);
122 }
123 }
124
125 /** this method returns the current value in the pick peaking buffer
126 * after smoothing
127 */
128 fvec_t *
aubio_peakpicker_get_thresholded_input(aubio_peakpicker_t * p)129 aubio_peakpicker_get_thresholded_input (aubio_peakpicker_t * p)
130 {
131 return p->thresholded;
132 }
133
134 uint_t
aubio_peakpicker_set_threshold(aubio_peakpicker_t * p,smpl_t threshold)135 aubio_peakpicker_set_threshold (aubio_peakpicker_t * p, smpl_t threshold)
136 {
137 p->threshold = threshold;
138 return AUBIO_OK;
139 }
140
141 smpl_t
aubio_peakpicker_get_threshold(aubio_peakpicker_t * p)142 aubio_peakpicker_get_threshold (aubio_peakpicker_t * p)
143 {
144 return p->threshold;
145 }
146
147 uint_t
aubio_peakpicker_set_thresholdfn(aubio_peakpicker_t * p,aubio_thresholdfn_t thresholdfn)148 aubio_peakpicker_set_thresholdfn (aubio_peakpicker_t * p,
149 aubio_thresholdfn_t thresholdfn)
150 {
151 p->thresholdfn = thresholdfn;
152 return AUBIO_OK;
153 }
154
155 aubio_thresholdfn_t
aubio_peakpicker_get_thresholdfn(aubio_peakpicker_t * p)156 aubio_peakpicker_get_thresholdfn (aubio_peakpicker_t * p)
157 {
158 return (aubio_thresholdfn_t) (p->thresholdfn);
159 }
160
161 aubio_peakpicker_t *
new_aubio_peakpicker(void)162 new_aubio_peakpicker (void)
163 {
164 aubio_peakpicker_t *t = AUBIO_NEW (aubio_peakpicker_t);
165 t->threshold = 0.1; /* 0.0668; 0.33; 0.082; 0.033; */
166 t->win_post = 5;
167 t->win_pre = 1;
168
169 t->thresholdfn = (aubio_thresholdfn_t) (fvec_median); /* (fvec_mean); */
170 t->pickerfn = (aubio_pickerfn_t) (fvec_peakpick);
171
172 t->scratch = new_fvec (t->win_post + t->win_pre + 1);
173 t->onset_keep = new_fvec (t->win_post + t->win_pre + 1);
174 t->onset_proc = new_fvec (t->win_post + t->win_pre + 1);
175 t->onset_peek = new_fvec (3);
176 t->thresholded = new_fvec (1);
177
178 /* cutoff: low-pass filter with cutoff reduced frequency at 0.34
179 generated with octave butter function: [b,a] = butter(2, 0.34);
180 */
181 t->biquad = new_aubio_filter_biquad (0.15998789, 0.31997577, 0.15998789,
182 // FIXME: broken since c9e20ca, revert for now
183 //-0.59488894, 0.23484048);
184 0.23484048, 0);
185
186 return t;
187 }
188
189 void
del_aubio_peakpicker(aubio_peakpicker_t * p)190 del_aubio_peakpicker (aubio_peakpicker_t * p)
191 {
192 del_aubio_filter (p->biquad);
193 del_fvec (p->onset_keep);
194 del_fvec (p->onset_proc);
195 del_fvec (p->onset_peek);
196 del_fvec (p->thresholded);
197 del_fvec (p->scratch);
198 AUBIO_FREE (p);
199 }
200