2 Copyright (C) 2007-2009 Paul Brossier <piem@aubio.org>
3 and Amaury Hazan <ahazan@iua.upf.edu>
5 This file is part of aubio.
7 aubio is free software: you can redistribute it and/or modify
8 it under the terms of the GNU General Public License as published by
9 the Free Software Foundation, either version 3 of the License, or
10 (at your option) any later version.
12 aubio is distributed in the hope that it will be useful,
13 but WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 GNU General Public License for more details.
17 You should have received a copy of the GNU General Public License
18 along with aubio. If not, see <http://www.gnu.org/licenses/>.
22 #include "aubio_priv.h"
26 #include "mathutils.h"
28 #include "spectral/fft.h"
29 #include "spectral/filterbank.h"
30 #include "spectral/filterbank_mel.h"
31 #include "spectral/dct.h"
32 #include "spectral/mfcc.h"
35 #define HAVE_SLOW_DCT 1
38 /** Internal structure for mfcc object */
42 uint_t win_s; /** grain length */
43 uint_t samplerate; /** sample rate (needed?) */
44 uint_t n_filters; /** number of filters */
45 uint_t n_coefs; /** number of coefficients (<= n_filters/2 +1) */
46 aubio_filterbank_t *fb; /** filter bank */
47 fvec_t *in_dct; /** input buffer for dct * [fb->n_filters] */
48 #if defined(HAVE_SLOW_DCT)
49 fmat_t *dct_coeffs; /** DCT transform n_filters * n_coeffs */
58 new_aubio_mfcc (uint_t win_s, uint_t n_filters, uint_t n_coefs,
62 /* allocate space for mfcc object */
63 aubio_mfcc_t *mfcc = AUBIO_NEW (aubio_mfcc_t);
64 #if defined(HAVE_SLOW_DCT)
71 mfcc->samplerate = samplerate;
72 mfcc->n_filters = n_filters;
73 mfcc->n_coefs = n_coefs;
75 /* filterbank allocation */
76 mfcc->fb = new_aubio_filterbank (n_filters, mfcc->win_s);
77 aubio_filterbank_set_mel_coeffs_slaney (mfcc->fb, samplerate);
79 /* allocating buffers */
80 mfcc->in_dct = new_fvec (n_filters);
82 #if defined(HAVE_SLOW_DCT)
83 mfcc->dct_coeffs = new_fmat (n_coefs, n_filters);
85 /* compute DCT transform dct_coeffs[j][i] as
86 cos ( j * (i+.5) * PI / n_filters ) */
87 scaling = 1. / SQRT (n_filters / 2.);
88 for (i = 0; i < n_filters; i++) {
89 for (j = 0; j < n_coefs; j++) {
90 mfcc->dct_coeffs->data[j][i] =
91 scaling * COS (j * (i + 0.5) * PI / n_filters);
93 mfcc->dct_coeffs->data[0][i] *= SQRT (2.) / 2.;
96 mfcc->dct = new_aubio_dct (n_filters);
97 mfcc->output = new_fvec (n_filters);
104 del_aubio_mfcc (aubio_mfcc_t * mf)
107 /* delete filterbank */
108 del_aubio_filterbank (mf->fb);
111 del_fvec (mf->in_dct);
112 #if defined(HAVE_SLOW_DCT)
113 del_fmat (mf->dct_coeffs);
115 del_aubio_dct (mf->dct);
116 del_fvec (mf->output);
119 /* delete mfcc object */
125 aubio_mfcc_do (aubio_mfcc_t * mf, const cvec_t * in, fvec_t * out)
127 #ifndef HAVE_SLOW_DCT
130 /* compute filterbank */
131 aubio_filterbank_do (mf->fb, in, mf->in_dct);
134 fvec_log10 (mf->in_dct);
137 //fvec_pow (mf->in_dct, 3.);
140 #if defined(HAVE_SLOW_DCT)
141 fmat_vecmul(mf->dct_coeffs, mf->in_dct, out);
143 aubio_dct_do(mf->dct, mf->in_dct, mf->output);
144 // copy only first n_coeffs elements
145 // TODO assert mf->output->length == n_coeffs
146 tmp.data = mf->output->data;
147 tmp.length = out->length;
148 fvec_copy(&tmp, out);
154 uint_t aubio_mfcc_set_power (aubio_mfcc_t *mf, smpl_t power)
156 return aubio_filterbank_set_power(mf->fb, power);
159 uint_t aubio_mfcc_get_power (aubio_mfcc_t *mf)
161 return aubio_filterbank_get_power(mf->fb);
164 uint_t aubio_mfcc_set_mel_coeffs (aubio_mfcc_t *mf, smpl_t freq_min,
167 return aubio_filterbank_set_mel_coeffs(mf->fb, mf->samplerate,
171 uint_t aubio_mfcc_set_mel_coeffs_htk (aubio_mfcc_t *mf, smpl_t freq_min,
174 return aubio_filterbank_set_mel_coeffs_htk(mf->fb, mf->samplerate,
178 uint_t aubio_mfcc_set_mel_coeffs_slaney (aubio_mfcc_t *mf, smpl_t freq_min,
181 return aubio_filterbank_set_mel_coeffs_slaney (mf->fb, mf->samplerate);