2 Copyright (C) 2006-2009 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/>.
23 Onset detection object
25 The following routines compute the onset detection function and detect peaks
26 in these functions. When onsets are found above a given silence threshold,
27 and after a minimum inter-onset interval, the output vector returned by
28 ::aubio_onset_do is filled with `1`. Otherwise, the output vector remains
31 The peak-picking threshold, the silence threshold, and the minimum
32 inter-onset interval can be adjusted during the execution of the
33 aubio_onset_do routine using the corresponding functions.
35 \example onset/test-onset.c
47 /** onset detection object */
48 typedef struct _aubio_onset_t aubio_onset_t;
50 /** create onset detection object
52 \param method onset detection type as specified in specdesc.h
53 \param buf_size buffer size for phase vocoder
54 \param hop_size hop size for phase vocoder
55 \param samplerate sampling rate of the input signal
58 aubio_onset_t * new_aubio_onset (char_t * method,
59 uint_t buf_size, uint_t hop_size, uint_t samplerate);
61 /** execute onset detection
63 \param o onset detection object as returned by ::new_aubio_onset
64 \param input new audio vector of length hop_size
65 \param onset output vector of length 1, containing 0 if no onset was found,
66 and a value equal or greater than 1 otherwise
68 When no onset was detected, the first element of the output vector `onset`
71 When an onset is found, the first element of the output vector `onset` is set
72 to `offset = 1 + a` where `a` is a number in the range`[0, 1]`.
74 The final onset detection time, in samples, can be obtained with
75 ::aubio_onset_get_last_onset. It can also be derived from `offset` as
79 t = total_frames + offset * hop_size - delay
82 where `total_frames` is the total number of frames processed so far, and
83 `delay` is the current delay of the onset object, as returned by
84 ::aubio_onset_get_delay.
87 void aubio_onset_do (aubio_onset_t *o, fvec_t * input, fvec_t * onset);
89 /** get the time of the latest onset detected, in samples
91 \param o onset detection object as returned by ::new_aubio_onset
94 uint_t aubio_onset_get_last (aubio_onset_t *o);
96 /** get the time of the latest onset detected, in seconds
98 \param o onset detection object as returned by ::new_aubio_onset
101 smpl_t aubio_onset_get_last_s (aubio_onset_t *o);
103 /** get the time of the latest onset detected, in milliseconds
105 \param o onset detection object as returned by ::new_aubio_onset
108 smpl_t aubio_onset_get_last_ms (aubio_onset_t *o);
110 /** set onset detection silence threshold
112 \param o onset detection object as returned by ::new_aubio_onset
113 \param silence new silence detection threshold
116 uint_t aubio_onset_set_silence(aubio_onset_t * o, smpl_t silence);
118 /** get onset detection function
120 \param o onset detection object as returned by ::new_aubio_onset
121 \return the current value of the descriptor
124 smpl_t aubio_onset_get_descriptor ( aubio_onset_t *o);
126 /** get thresholded onset detection function
128 \param o onset detection object as returned by ::new_aubio_onset
129 \return the value of the thresholded descriptor
132 smpl_t aubio_onset_get_thresholded_descriptor ( aubio_onset_t *o);
134 /** set onset detection peak picking threshold
136 \param o onset detection object as returned by ::new_aubio_onset
137 \param threshold new peak-picking threshold
140 uint_t aubio_onset_set_threshold(aubio_onset_t * o, smpl_t threshold);
142 /** set minimum inter onset interval in samples
144 \param o onset detection object as returned by ::new_aubio_onset
145 \param minioi minimum interval between two consecutive onsets (in
149 uint_t aubio_onset_set_minioi(aubio_onset_t * o, uint_t minioi);
151 /** set minimum inter onset interval in seconds
153 \param o onset detection object as returned by ::new_aubio_onset
154 \param minioi minimum interval between two consecutive onsets (in
158 uint_t aubio_onset_set_minioi_s(aubio_onset_t * o, smpl_t minioi);
160 /** set minimum inter onset interval in milliseconds
162 \param o onset detection object as returned by ::new_aubio_onset
163 \param minioi minimum interval between two consecutive onsets (in
167 uint_t aubio_onset_set_minioi_ms(aubio_onset_t * o, smpl_t minioi);
169 /** set minimum inter onset interval in samples
171 \param o onset detection object as returned by ::new_aubio_onset
172 \param delay constant system delay to take back from detection time
176 uint_t aubio_onset_set_delay(aubio_onset_t * o, uint_t delay);
178 /** set minimum inter onset interval in seconds
180 \param o onset detection object as returned by ::new_aubio_onset
181 \param delay constant system delay to take back from detection time
185 uint_t aubio_onset_set_delay_s(aubio_onset_t * o, smpl_t delay);
187 /** set minimum inter onset interval in milliseconds
189 \param o onset detection object as returned by ::new_aubio_onset
190 \param delay constant system delay to take back from detection time
194 uint_t aubio_onset_set_delay_ms(aubio_onset_t * o, smpl_t delay);
196 /** get minimum inter onset interval in samples
198 \param o onset detection object as returned by ::new_aubio_onset
199 \return minimum interval between two consecutive onsets (in
203 uint_t aubio_onset_get_minioi(aubio_onset_t * o);
205 /** get minimum inter onset interval in seconds
207 \param o onset detection object as returned by ::new_aubio_onset
208 \return minimum interval between two consecutive onsets (in
212 smpl_t aubio_onset_get_minioi_s(aubio_onset_t * o);
214 /** get minimum inter onset interval in milliseconds
216 \param o onset detection object as returned by ::new_aubio_onset
217 \return minimum interval between two consecutive onsets (in
221 smpl_t aubio_onset_get_minioi_ms(aubio_onset_t * o);
223 /** get minimum inter onset interval in samples
225 \param o onset detection object as returned by ::new_aubio_onset
226 \return constant system delay to take back from detection time
230 uint_t aubio_onset_get_delay(aubio_onset_t * o);
232 /** get minimum inter onset interval in seconds
234 \param o onset detection object as returned by ::new_aubio_onset
235 \return constant system delay to take back from detection time
239 smpl_t aubio_onset_get_delay_s(aubio_onset_t * o);
241 /** get minimum inter onset interval in milliseconds
243 \param o onset detection object as returned by ::new_aubio_onset
244 \return constant system delay to take back from detection time
248 smpl_t aubio_onset_get_delay_ms(aubio_onset_t * o);
250 /** delete onset detection object
252 \param o onset detection object to delete
255 void del_aubio_onset(aubio_onset_t * o);