2 Copyright (C) 2003-2009 Paul Brossier <piem@aubio.org>
4 This file is part of aubio.
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.
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.
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/>.
21 #include "aubio_priv.h"
23 #include "mathutils.h"
25 #include "temporal/filter.h"
26 #include "temporal/biquad.h"
27 #include "onset/peakpicker.h"
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);
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);
39 /* peak picking parameters, default values in brackets
41 * [<----post----|--pre-->]
42 * .................|.............
45 struct _aubio_peakpicker_t
47 /** thresh: offset threshold [0.033 or 0.01] */
49 /** win_post: median filter window length (causal part) [8] */
51 /** pre: median filter window (anti-causal part) [post-1] */
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;
58 /** biquad lowpass filter */
59 aubio_filter_t *biquad;
60 /** original onsets */
62 /** modified onsets */
64 /** peak picked window [3] */
66 /** thresholded function */
68 /** scratch pad for biquad and median */
71 /** \bug should be used to calculate filter coefficients */
72 /* cutoff: low-pass filter cutoff [0.34, 1] */
75 /* not used anymore */
76 /* time precision [512/44100 winlength/samplerate, fs/buffer_size */
78 /* alpha: normalisation exponent [9] */
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 */
87 aubio_peakpicker_do (aubio_peakpicker_t * p, fvec_t * onset, fvec_t * out)
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;
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];
104 onset_keep->data[length - 1] = onset->data[0];
105 onset_proc->data[length - 1] = onset->data[0];
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);
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);
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);
127 out->data[0] = fvec_quadratic_peak_pos (onset_peek, 1);
131 /** this method returns the current value in the pick peaking buffer
135 aubio_peakpicker_get_thresholded_input (aubio_peakpicker_t * p)
137 return p->thresholded;
141 aubio_peakpicker_set_threshold (aubio_peakpicker_t * p, smpl_t threshold)
143 p->threshold = threshold;
148 aubio_peakpicker_get_threshold (aubio_peakpicker_t * p)
154 aubio_peakpicker_set_thresholdfn (aubio_peakpicker_t * p,
155 aubio_thresholdfn_t thresholdfn)
157 p->thresholdfn = thresholdfn;
162 aubio_peakpicker_get_thresholdfn (aubio_peakpicker_t * p)
164 return (aubio_thresholdfn_t) (p->thresholdfn);
168 new_aubio_peakpicker (void)
170 aubio_peakpicker_t *t = AUBIO_NEW (aubio_peakpicker_t);
171 t->threshold = 0.1; /* 0.0668; 0.33; 0.082; 0.033; */
175 t->thresholdfn = (aubio_thresholdfn_t) (fvec_median); /* (fvec_mean); */
176 t->pickerfn = (aubio_pickerfn_t) (fvec_peakpick);
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);
184 /* cutoff: low-pass filter with cutoff reduced frequency at 0.34
185 generated with octave butter function: [b,a] = butter(2, 0.34);
187 t->biquad = new_aubio_filter_biquad (0.15998789, 0.31997577, 0.15998789,
188 // FIXME: broken since c9e20ca, revert for now
189 //-0.59488894, 0.23484048);
196 del_aubio_peakpicker (aubio_peakpicker_t * p)
198 del_aubio_filter (p->biquad);
199 del_fvec (p->onset_keep);
200 del_fvec (p->onset_proc);
201 del_fvec (p->onset_peek);
202 del_fvec (p->thresholded);
203 del_fvec (p->scratch);