ref: e3b77e8f99c1e4ab03f79fcbb2c64efe633aa2b2
dir: /src/pitch/pitchyin.c/
/* Copyright (C) 2003-2009 Paul Brossier <piem@aubio.org> This file is part of aubio. aubio 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 3 of the License, or (at your option) any later version. aubio 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 aubio. If not, see <http://www.gnu.org/licenses/>. */ /* This algorithm was developed by A. de Cheveigné and H. Kawahara and * published in: * * de Cheveigné, A., Kawahara, H. (2002) "YIN, a fundamental frequency * estimator for speech and music", J. Acoust. Soc. Am. 111, 1917-1930. * * see http://recherche.ircam.fr/equipes/pcm/pub/people/cheveign.html */ #include "aubio_priv.h" #include "fvec.h" #include "mathutils.h" #include "pitch/pitchyin.h" struct _aubio_pitchyin_t { fvec_t *yin; smpl_t tol; smpl_t confidence; }; /** compute difference function \param input input signal \param yinbuf output buffer to store difference function (half shorter than input) */ void aubio_pitchyin_diff (fvec_t * input, fvec_t * yinbuf); /** in place computation of the YIN cumulative normalised function \param yinbuf input signal (a square difference function), also used to store function */ void aubio_pitchyin_getcum (fvec_t * yinbuf); /** detect pitch in a YIN function \param yinbuf input buffer as computed by aubio_pitchyin_getcum */ uint_t aubio_pitchyin_getpitch (const fvec_t * yinbuf); aubio_pitchyin_t * new_aubio_pitchyin (uint_t bufsize) { aubio_pitchyin_t *o = AUBIO_NEW (aubio_pitchyin_t); o->yin = new_fvec (bufsize / 2); o->tol = 0.15; return o; } void del_aubio_pitchyin (aubio_pitchyin_t * o) { del_fvec (o->yin); AUBIO_FREE (o); } /* outputs the difference function */ void aubio_pitchyin_diff (fvec_t * input, fvec_t * yin) { uint_t j, tau; smpl_t tmp; for (tau = 0; tau < yin->length; tau++) { yin->data[tau] = 0.; } for (tau = 1; tau < yin->length; tau++) { for (j = 0; j < yin->length; j++) { tmp = input->data[j] - input->data[j + tau]; yin->data[tau] += SQR (tmp); } } } /* cumulative mean normalized difference function */ void aubio_pitchyin_getcum (fvec_t * yin) { uint_t tau; smpl_t tmp = 0.; yin->data[0] = 1.; //AUBIO_DBG("%f\t",yin->data[0]); for (tau = 1; tau < yin->length; tau++) { tmp += yin->data[tau]; yin->data[tau] *= tau / tmp; //AUBIO_DBG("%f\t",yin->data[tau]); } //AUBIO_DBG("\n"); } uint_t aubio_pitchyin_getpitch (const fvec_t * yin) { uint_t tau = 1; do { if (yin->data[tau] < 0.1) { while (yin->data[tau + 1] < yin->data[tau]) { tau++; } return tau; } tau++; } while (tau < yin->length); //AUBIO_DBG("No pitch found"); return 0; } /* all the above in one */ void aubio_pitchyin_do (aubio_pitchyin_t * o, const fvec_t * input, fvec_t * out) { const smpl_t tol = o->tol; fvec_t* yin = o->yin; const smpl_t *input_data = input->data; const uint_t length = yin->length; smpl_t *yin_data = yin->data; uint_t j, tau; sint_t period; smpl_t tmp, tmp2 = 0.; yin_data[0] = 1.; for (tau = 1; tau < length; tau++) { yin_data[tau] = 0.; for (j = 0; j < length; j++) { tmp = input_data[j] - input_data[j + tau]; yin_data[tau] += SQR (tmp); } tmp2 += yin_data[tau]; if (tmp2 != 0) { yin->data[tau] *= tau / tmp2; } else { yin->data[tau] = 1.; } period = tau - 3; if (tau > 4 && (yin_data[period] < tol) && (yin_data[period] < yin_data[period + 1])) { out->data[0] = fvec_quadratic_peak_pos (yin, period); goto beach; } } out->data[0] = fvec_quadratic_peak_pos (yin, fvec_min_elem (yin)); beach: return; } smpl_t aubio_pitchyin_get_confidence (aubio_pitchyin_t * o) { o->confidence = 1. - fvec_min (o->yin); return o->confidence; } uint_t aubio_pitchyin_set_tolerance (aubio_pitchyin_t * o, smpl_t tol) { o->tol = tol; return 0; } smpl_t aubio_pitchyin_get_tolerance (aubio_pitchyin_t * o) { return o->tol; }