2 Copyright (C) 2007-2009 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/>.
21 #include "aubio_priv.h"
23 #include "spectral/specdesc.h"
25 void aubio_specdesc_centroid (aubio_specdesc_t * o, const cvec_t * spec,
27 void aubio_specdesc_spread (aubio_specdesc_t * o, const cvec_t * spec,
29 void aubio_specdesc_skewness (aubio_specdesc_t * o, const cvec_t * spec,
31 void aubio_specdesc_kurtosis (aubio_specdesc_t * o, const cvec_t * spec,
33 void aubio_specdesc_slope (aubio_specdesc_t * o, const cvec_t * spec,
35 void aubio_specdesc_decrease (aubio_specdesc_t * o, const cvec_t * spec,
37 void aubio_specdesc_rolloff (aubio_specdesc_t * o, const cvec_t * spec,
41 smpl_t cvec_sum (const cvec_t * s);
42 smpl_t cvec_mean (const cvec_t * s);
43 smpl_t cvec_centroid (const cvec_t * s);
44 smpl_t cvec_moment (const cvec_t * s, uint_t moment);
47 cvec_sum (const cvec_t * s)
51 for (j = 0; j < s->length; j++) {
58 cvec_mean (const cvec_t * s)
60 return cvec_sum (s) / (smpl_t) (s->length);
64 cvec_centroid (const cvec_t * spec)
66 smpl_t sum = 0., sc = 0.;
68 sum = cvec_sum (spec);
72 for (j = 0; j < spec->length; j++) {
73 sc += (smpl_t) j *spec->norm[j];
80 cvec_moment (const cvec_t * spec, uint_t order)
82 smpl_t sum = 0., centroid = 0., sc = 0.;
84 sum = cvec_sum (spec);
88 centroid = cvec_centroid (spec);
89 for (j = 0; j < spec->length; j++) {
90 sc += (smpl_t) POW(j - centroid, order) * spec->norm[j];
97 aubio_specdesc_centroid (aubio_specdesc_t * o UNUSED, const cvec_t * spec,
100 desc->data[0] = cvec_centroid (spec);
104 aubio_specdesc_spread (aubio_specdesc_t * o UNUSED, const cvec_t * spec,
107 desc->data[0] = cvec_moment (spec, 2);
111 aubio_specdesc_skewness (aubio_specdesc_t * o UNUSED, const cvec_t * spec,
115 spread = cvec_moment (spec, 2);
119 desc->data[0] = cvec_moment (spec, 3);
120 desc->data[0] /= POW ( SQRT (spread), 3);
125 aubio_specdesc_kurtosis (aubio_specdesc_t * o UNUSED, const cvec_t * spec,
129 spread = cvec_moment (spec, 2);
133 desc->data[0] = cvec_moment (spec, 4);
134 desc->data[0] /= SQR (spread);
139 aubio_specdesc_slope (aubio_specdesc_t * o UNUSED, const cvec_t * spec,
143 smpl_t norm = 0, sum = 0.;
144 // compute N * sum(j**2) - sum(j)**2
145 for (j = 0; j < spec->length; j++) {
148 norm *= spec->length;
149 // sum_0^N(j) = length * (length + 1) / 2
150 norm -= SQR( (spec->length) * (spec->length - 1.) / 2. );
151 sum = cvec_sum (spec);
156 for (j = 0; j < spec->length; j++) {
157 desc->data[0] += j * spec->norm[j];
159 desc->data[0] *= spec->length;
160 desc->data[0] -= sum * spec->length * (spec->length - 1) / 2.;
161 desc->data[0] /= norm;
162 desc->data[0] /= sum;
167 aubio_specdesc_decrease (aubio_specdesc_t *o UNUSED, const cvec_t * spec,
170 uint_t j; smpl_t sum;
171 sum = cvec_sum (spec);
176 sum -= spec->norm[0];
177 for (j = 1; j < spec->length; j++) {
178 desc->data[0] += (spec->norm[j] - spec->norm[0]) / j;
180 desc->data[0] /= sum;
185 aubio_specdesc_rolloff (aubio_specdesc_t *o UNUSED, const cvec_t * spec,
188 uint_t j; smpl_t cumsum, rollsum;
189 cumsum = 0.; rollsum = 0.;
190 for (j = 0; j < spec->length; j++) {
191 cumsum += SQR (spec->norm[j]);
198 while (rollsum < cumsum) {
199 rollsum += SQR (spec->norm[j]);