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/>.
23 Pitch detection using a Schmitt trigger
25 This pitch extraction method implements a Schmitt trigger to estimate the
28 This file was derived from the tuneit project, written by Mario Lang to
29 detect the fundamental frequency of a sound.
31 see http://delysid.org/tuneit.html
35 #ifndef _PITCHSCHMITT_H
36 #define _PITCHSCHMITT_H
42 /** pitch detection object */
43 typedef struct _aubio_pitchschmitt_t aubio_pitchschmitt_t;
45 /** execute pitch detection on an input buffer
47 \param p pitch detection object as returned by new_aubio_pitchschmitt
48 \param input input signal window (length as specified at creation time)
49 \param output pitch period estimates, in samples
52 void aubio_pitchschmitt_do (aubio_pitchschmitt_t * p, fvec_t * in,
55 /** creation of the pitch detection object
57 \param buf_size size of the input buffer to analyse
60 aubio_pitchschmitt_t *new_aubio_pitchschmitt (uint_t buf_size);
62 /** deletion of the pitch detection object
64 \param p pitch detection object as returned by new_aubio_pitchschmitt
67 void del_aubio_pitchschmitt (aubio_pitchschmitt_t * p);
73 #endif /* _PITCHSCHMITT_H */