/*
- Copyright (C) 2006 Amaury Hazan
- Ported to aubio from LibXtract
- http://libxtract.sourceforge.net/
-
+ Copyright (C) 2007-2009 Paul Brossier <piem@aubio.org>
+ and Amaury Hazan <ahazan@iua.upf.edu>
- 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 file is part of aubio.
- 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.
+ 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.
- 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.
+ 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/>.
*/
#include "aubio_priv.h"
#include "fvec.h"
+#include "fmat.h"
#include "cvec.h"
+#include "mathutils.h"
+#include "vecutils.h"
#include "spectral/fft.h"
#include "spectral/filterbank.h"
+#include "spectral/filterbank_mel.h"
#include "spectral/mfcc.h"
-/** Internal structure for mfcc object **/
+/** Internal structure for mfcc object */
-struct aubio_mfcc_t_{
+struct _aubio_mfcc_t
+{
uint_t win_s; /** grain length */
uint_t samplerate; /** sample rate (needed?) */
- uint_t channels; /** number of channels */
- uint_t n_filters; /** number of *filters */
+ uint_t n_filters; /** number of filters */
uint_t n_coefs; /** number of coefficients (<= n_filters/2 +1) */
- smpl_t lowfreq; /** lowest frequency for filters */
- smpl_t highfreq; /** highest frequency for filters */
- aubio_filterbank_t * fb; /** filter bank */
- fvec_t * in_dct; /** input buffer for dct * [fb->n_filters] */
- aubio_fft_t * fft_dct; /** fft object for dct */
- cvec_t * fftgrain_dct; /** output buffer for dct */
+ aubio_filterbank_t *fb; /** filter bank */
+ fvec_t *in_dct; /** input buffer for dct * [fb->n_filters] */
+ fmat_t *dct_coeffs; /** DCT transform n_filters * n_coeffs */
};
-aubio_mfcc_t * new_aubio_mfcc (uint_t win_s, uint_t samplerate, uint_t n_filters, uint_t n_coefs, smpl_t lowfreq, smpl_t highfreq, uint_t channels){
- /** allocating space for mfcc object */
- aubio_mfcc_t * mfcc = AUBIO_NEW(aubio_mfcc_t);
+aubio_mfcc_t *
+new_aubio_mfcc (uint_t win_s, uint_t n_filters, uint_t n_coefs,
+ uint_t samplerate)
+{
- //we need (n_coefs-1)*2 filters to obtain n_coefs coefficients after dct
- //uint_t n_filters = (n_coefs-1)*2;
-
- mfcc->win_s=win_s;
- mfcc->samplerate=samplerate;
- mfcc->channels=channels;
- mfcc->n_filters=n_filters;
- mfcc->n_coefs=n_coefs;
- mfcc->lowfreq=lowfreq;
- mfcc->highfreq=highfreq;
+ /* allocate space for mfcc object */
+ aubio_mfcc_t *mfcc = AUBIO_NEW (aubio_mfcc_t);
+ smpl_t scaling;
-
- /** filterbank allocation */
- mfcc->fb = new_aubio_filterbank_mfcc(n_filters, mfcc->win_s, samplerate, lowfreq, highfreq);
+ uint_t i, j;
- /** allocating space for fft object (used for dct) */
- mfcc->fft_dct=new_aubio_fft(n_filters, 1);
+ mfcc->win_s = win_s;
+ mfcc->samplerate = samplerate;
+ mfcc->n_filters = n_filters;
+ mfcc->n_coefs = n_coefs;
- /** allocating buffers */
- mfcc->in_dct=new_fvec(mfcc->win_s, 1);
-
- mfcc->fftgrain_dct=new_cvec(n_filters, 1);
+ /* filterbank allocation */
+ mfcc->fb = new_aubio_filterbank (n_filters, mfcc->win_s);
+ aubio_filterbank_set_mel_coeffs_slaney (mfcc->fb, samplerate);
- return mfcc;
-};
+ /* allocating buffers */
+ mfcc->in_dct = new_fvec (n_filters);
+
+ mfcc->dct_coeffs = new_fmat (n_coefs, n_filters);
-void del_aubio_mfcc(aubio_mfcc_t *mf){
- /** deleting filterbank */
- del_aubio_filterbank(mf->fb);
- /** deleting fft object */
- del_aubio_fft(mf->fft_dct);
- /** deleting buffers */
- del_fvec(mf->in_dct);
- del_cvec(mf->fftgrain_dct);
-
- /** deleting mfcc object */
- AUBIO_FREE(mf);
+ /* compute DCT transform dct_coeffs[j][i] as
+ cos ( j * (i+.5) * PI / n_filters ) */
+ scaling = 1. / SQRT (n_filters / 2.);
+ for (i = 0; i < n_filters; i++) {
+ for (j = 0; j < n_coefs; j++) {
+ mfcc->dct_coeffs->data[j][i] =
+ scaling * COS (j * (i + 0.5) * PI / n_filters);
+ }
+ mfcc->dct_coeffs->data[0][i] *= SQRT (2.) / 2.;
+ }
+
+ return mfcc;
}
+void
+del_aubio_mfcc (aubio_mfcc_t * mf)
+{
-/** intermediate dct involved in aubio_mfcc_do
+ /* delete filterbank */
+ del_aubio_filterbank (mf->fb);
- \param mf mfcc object as returned by new_aubio_mfcc
- \param in input spectrum (n_filters long)
- \param out output mel coefficients buffer (n_filters/2 +1 long)
+ /* delete buffers */
+ del_fvec (mf->in_dct);
+ del_fmat (mf->dct_coeffs);
-*/
-void aubio_dct_do(aubio_mfcc_t * mf, fvec_t *in, fvec_t *out);
-
-void aubio_mfcc_do(aubio_mfcc_t * mf, cvec_t *in, fvec_t *out){
- // compute filterbank
- aubio_filterbank_do(mf->fb, in, mf->in_dct);
- //TODO: check that zero padding
- // the following line seems useless since the in_dct buffer has the correct size
- //for(n = filter + 1; n < N; n++) result[n] = 0;
-
- aubio_dct_do(mf, mf->in_dct, out);
-
- return;
+ /* delete mfcc object */
+ AUBIO_FREE (mf);
}
-void aubio_dct_do(aubio_mfcc_t * mf, fvec_t *in, fvec_t *out){
- uint_t i;
- //compute mag spectrum
- aubio_fft_do (mf->fft_dct, in, mf->fftgrain_dct);
- //extract real part of fft grain
- for(i=0; i<mf->n_coefs ;i++){
- //for(i=0; i<out->length;i++){
- out->data[0][i]= mf->fftgrain_dct->norm[0][i]
- *COS(mf->fftgrain_dct->phas[0][i]);
- }
- return;
-}
+void
+aubio_mfcc_do (aubio_mfcc_t * mf, const cvec_t * in, fvec_t * out)
+{
+ /* compute filterbank */
+ aubio_filterbank_do (mf->fb, in, mf->in_dct);
+
+ /* compute log10 */
+ fvec_log10 (mf->in_dct);
+
+ /* raise power */
+ //fvec_pow (mf->in_dct, 3.);
+
+ /* compute mfccs */
+ fmat_vecmul(mf->dct_coeffs, mf->in_dct, out);
+
+ return;
+}
projects / aubio.git / blobdiff