/* Copyright (C) 2003 Paul Brossier This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version. This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with this program; if not, write to the Free Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */ /** \file Pitch detection using a Schmitt trigger This pitch extraction method implements a Schmitt trigger to estimate the period of a signal. This file was derived from the tuneit project, written by Mario Lang to detect the fundamental frequency of a sound. see http://delysid.org/tuneit.html */ #ifndef _PITCHSCHMITT_H #define _PITCHSCHMITT_H #ifdef __cplusplus extern "C" { #endif /** pitch detection object */ typedef struct _aubio_pitchschmitt_t aubio_pitchschmitt_t; /** execute pitch detection on an input buffer \param p pitch detection object as returned by new_aubio_pitchschmitt \param input input signal window (length as specified at creation time) */ smpl_t aubio_pitchschmitt_detect (aubio_pitchschmitt_t *p, fvec_t * input); /** creation of the pitch detection object \param size size of the input buffer to analyse \param samplerate sampling rate of the signal */ aubio_pitchschmitt_t * new_aubio_pitchschmitt (uint_t size, uint_t samplerate); /** deletion of the pitch detection object \param p pitch detection object as returned by new_aubio_pitchschmitt */ void del_aubio_pitchschmitt (aubio_pitchschmitt_t *p); #ifdef __cplusplus } #endif #endif /* _PITCHSCHMITT_H */