aubio: pitch/pitch.h Source File

aubio 0.4.9

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pitch.h
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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#ifndef AUBIO_PITCH_H
22#define AUBIO_PITCH_H
23
24#ifdef __cplusplus
25extern "C" {
26#endif
27
28/** \file
29
30 Pitch detection object
31
32 This file creates the objects required for the computation of the selected
33 pitch detection algorithm and output the results, in midi note or Hz.
34
35 \section pitch Pitch detection methods
36
37 A list of the pitch detection methods currently available follows.
38
39 \b \p default : use the default method
40
41 Currently, the default method is set to \p yinfft .
42
43 \b \p schmitt : Schmitt trigger
44
45 This pitch extraction method implements a Schmitt trigger to estimate the
46 period of a signal.
47
48 This file was derived from the tuneit project, written by Mario Lang to
49 detect the fundamental frequency of a sound.
50
51 See http://delysid.org/tuneit.html
52
53 \b \p fcomb : a fast harmonic comb filter
54
55 This pitch extraction method implements a fast harmonic comb filter to
56 determine the fundamental frequency of a harmonic sound.
57
58 This file was derived from the tuneit project, written by Mario Lang to
59 detect the fundamental frequency of a sound.
60
61 See http://delysid.org/tuneit.html
62
63 \b \p mcomb : multiple-comb filter
64
65 This fundamental frequency estimation algorithm implements spectral
66 flattening, multi-comb filtering and peak histogramming.
67
68 This method was designed by Juan P. Bello and described in:
69
70 Juan-Pablo Bello. ``Towards the Automated Analysis of Simple Polyphonic
71 Music''. PhD thesis, Centre for Digital Music, Queen Mary University of
72 London, London, UK, 2003.
73
74 \b \p yin : YIN algorithm
75
76 This algorithm was developed by A. de Cheveigne and H. Kawahara and
77 published in:
78
79 De Cheveigné, A., Kawahara, H. (2002) "YIN, a fundamental frequency
80 estimator for speech and music", J. Acoust. Soc. Am. 111, 1917-1930.
81
82 see http://recherche.ircam.fr/equipes/pcm/pub/people/cheveign.html
83
84 \b \p yinfast : Yinfast algorithm
85
86 This algorithm is equivalent to the YIN algorithm, but computed in the
87 spectral domain for efficiency. See also `python/demos/demo_yin_compare.py`.
88
89 \b \p yinfft : Yinfft algorithm
90
91 This algorithm was derived from the YIN algorithm. In this implementation, a
92 Fourier transform is used to compute a tapered square difference function,
93 which allows spectral weighting. Because the difference function is tapered,
94 the selection of the period is simplified.
95
96 Paul Brossier, [Automatic annotation of musical audio for interactive
97 systems](http://aubio.org/phd/), Chapter 3, Pitch Analysis, PhD thesis,
98 Centre for Digital music, Queen Mary University of London, London, UK, 2006.
99
100 \example pitch/test-pitch.c
101 \example examples/aubiopitch.c
102
103*/
104
105/** pitch detection object */
106 typedef struct _aubio_pitch_t aubio_pitch_t;
107
108/** execute pitch detection on an input signal frame
109
110 \param o pitch detection object as returned by new_aubio_pitch()
111 \param in input signal of size [hop_size]
112 \param out output pitch candidates of size [1]
113
114*/
115 void aubio_pitch_do (aubio_pitch_t * o, const fvec_t * in, fvec_t * out);
116
117/** change yin or yinfft tolerance threshold
118
119 \param o pitch detection object as returned by new_aubio_pitch()
120 \param tol tolerance default is 0.15 for yin and 0.85 for yinfft
121
122*/
123 uint_t aubio_pitch_set_tolerance (aubio_pitch_t * o, smpl_t tol);
124
125/** get yin or yinfft tolerance threshold
126
127 \param o pitch detection object as returned by new_aubio_pitch()
128 \return tolerance (default is 0.15 for yin and 0.85 for yinfft)
129
130*/
131 smpl_t aubio_pitch_get_tolerance (aubio_pitch_t * o);
132
133/** deletion of the pitch detection object
134
135 \param o pitch detection object as returned by new_aubio_pitch()
136
137*/
138 void del_aubio_pitch (aubio_pitch_t * o);
139
140/** creation of the pitch detection object
141
142 \param method set pitch detection algorithm
143 \param buf_size size of the input buffer to analyse
144 \param hop_size step size between two consecutive analysis instant
145 \param samplerate sampling rate of the signal
146
147 \return newly created ::aubio_pitch_t
148
149*/
150 aubio_pitch_t *new_aubio_pitch (const char_t * method,
151 uint_t buf_size, uint_t hop_size, uint_t samplerate);
152
153/** set the output unit of the pitch detection object
154
155 \param o pitch detection object as returned by new_aubio_pitch()
156 \param mode set pitch units for output
157
158 mode can be one of "Hz", "midi", "cent", or "bin". Defaults to "Hz".
159
160 \return 0 if successfull, non-zero otherwise
161
162*/
163 uint_t aubio_pitch_set_unit (aubio_pitch_t * o, const char_t * mode);
164
165/** set the silence threshold of the pitch detection object
166
167 \param o pitch detection object as returned by new_aubio_pitch()
168 \param silence level threshold under which pitch should be ignored, in dB
169
170 \return 0 if successfull, non-zero otherwise
171
172*/
173 uint_t aubio_pitch_set_silence (aubio_pitch_t * o, smpl_t silence);
174
175/** set the silence threshold of the pitch detection object
176
177 \param o pitch detection object as returned by ::new_aubio_pitch()
178
179 \return level threshold under which pitch should be ignored, in dB
180
181*/
182 smpl_t aubio_pitch_get_silence (aubio_pitch_t * o);
183
184/** get the current confidence
185
186 \param o pitch detection object as returned by new_aubio_pitch()
187
188 \return the current confidence of the pitch algorithm
189
190*/
191 smpl_t aubio_pitch_get_confidence (aubio_pitch_t * o);
192
193#ifdef __cplusplus
194}
195#endif
196
197#endif /* AUBIO_PITCH_H */
aubio_pitch_set_unit
uint_t aubio_pitch_set_unit(aubio_pitch_t *o, const char_t *mode)
set the output unit of the pitch detection object
aubio_pitch_do
void aubio_pitch_do(aubio_pitch_t *o, const fvec_t *in, fvec_t *out)
execute pitch detection on an input signal frame
aubio_pitch_get_silence
smpl_t aubio_pitch_get_silence(aubio_pitch_t *o)
set the silence threshold of the pitch detection object
del_aubio_pitch
void del_aubio_pitch(aubio_pitch_t *o)
deletion of the pitch detection object
new_aubio_pitch
aubio_pitch_t * new_aubio_pitch(const char_t *method, uint_t buf_size, uint_t hop_size, uint_t samplerate)
creation of the pitch detection object
aubio_pitch_get_tolerance
smpl_t aubio_pitch_get_tolerance(aubio_pitch_t *o)
get yin or yinfft tolerance threshold
aubio_pitch_get_confidence
smpl_t aubio_pitch_get_confidence(aubio_pitch_t *o)
get the current confidence
aubio_pitch_set_tolerance
uint_t aubio_pitch_set_tolerance(aubio_pitch_t *o, smpl_t tol)
change yin or yinfft tolerance threshold
aubio_pitch_t
struct _aubio_pitch_t aubio_pitch_t
pitch detection object
Definition: pitch.h:106
aubio_pitch_set_silence
uint_t aubio_pitch_set_silence(aubio_pitch_t *o, smpl_t silence)
set the silence threshold of the pitch detection object
fvec_t
Buffer for real data.
Definition: fvec.h:67
uint_t
unsigned int uint_t
unsigned integer
Definition: types.h:60
char_t
char char_t
character
Definition: types.h:64
smpl_t
float smpl_t
short sample format (32 or 64 bits)
Definition: types.h:41