aubio  0.4.9
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
25 extern "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 Cheveign√©, 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 */
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 */
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 */
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 */
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 */
192 
193 #ifdef __cplusplus
194 }
195 #endif
196 
197 #endif /* AUBIO_PITCH_H */
uint_t aubio_pitch_set_unit(aubio_pitch_t *o, const char_t *mode)
set the output unit of the pitch detection object
float smpl_t
short sample format (32 or 64 bits)
Definition: types.h:41
uint_t aubio_pitch_set_silence(aubio_pitch_t *o, smpl_t silence)
set the silence threshold of the pitch detection object
smpl_t aubio_pitch_get_silence(aubio_pitch_t *o)
set the silence threshold of the pitch detection object
uint_t aubio_pitch_set_tolerance(aubio_pitch_t *o, smpl_t tol)
change yin or yinfft tolerance threshold
void del_aubio_pitch(aubio_pitch_t *o)
deletion of the pitch detection object
smpl_t aubio_pitch_get_confidence(aubio_pitch_t *o)
get the current confidence
Buffer for real data.
Definition: fvec.h:67
void aubio_pitch_do(aubio_pitch_t *o, const fvec_t *in, fvec_t *out)
execute pitch detection on an input signal frame
unsigned int uint_t
unsigned integer
Definition: types.h:60
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
smpl_t aubio_pitch_get_tolerance(aubio_pitch_t *o)
get yin or yinfft tolerance threshold
char char_t
character
Definition: types.h:64
struct _aubio_pitch_t aubio_pitch_t
pitch detection object
Definition: pitch.h:106