source: src/temporal/biquad.c @ 6c7d49b

feature/autosinkfeature/cnnfeature/cnn_orgfeature/constantqfeature/crepefeature/crepe_orgfeature/pitchshiftfeature/pydocstringsfeature/timestretchfix/ffmpeg5pitchshiftsamplertimestretchyinfft+
Last change on this file since 6c7d49b was 6c7d49b, checked in by Paul Brossier <piem@piem.org>, 16 years ago

remove src/sample.h

  • Property mode set to 100644
File size: 2.7 KB
Line 
1/*
2   Copyright (C) 2003 Paul Brossier
3
4   This program is free software; you can redistribute it and/or modify
5   it under the terms of the GNU General Public License as published by
6   the Free Software Foundation; either version 2 of the License, or
7   (at your option) any later version.
8
9   This program is distributed in the hope that it will be useful,
10   but WITHOUT ANY WARRANTY; without even the implied warranty of
11   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
12   GNU General Public License for more details.
13
14   You should have received a copy of the GNU General Public License
15   along with this program; if not, write to the Free Software
16   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
17
18*/
19
20#include "aubio_priv.h"
21#include "fvec.h"
22#include "mathutils.h"
23#include "temporal/biquad.h"
24
25/** \note this file needs to be in double or more less precision would lead to large
26 * errors in the output
27 */
28
29struct _aubio_biquad_t {
30  lsmp_t a2;
31  lsmp_t a3;
32  lsmp_t b1;
33  lsmp_t b2;
34  lsmp_t b3;
35  lsmp_t o1;
36  lsmp_t o2;
37  lsmp_t i1;
38  lsmp_t i2;
39};
40
41void aubio_biquad_do(aubio_biquad_t * b, fvec_t * in) {
42  uint_t i,j;
43  lsmp_t i1 = b->i1;
44  lsmp_t i2 = b->i2;
45  lsmp_t o1 = b->o1;
46  lsmp_t o2 = b->o2;
47  lsmp_t a2 = b->a2;
48  lsmp_t a3 = b->a3;
49  lsmp_t b1 = b->b1;
50  lsmp_t b2 = b->b2;
51  lsmp_t b3 = b->b3;
52
53  i=0; // works in mono only !!!
54  //for (i=0;i<in->channels;i++) {
55  for (j = 0; j < in->length; j++) {
56    lsmp_t i0 = in->data[i][j];
57    lsmp_t o0 = b1 * i0 + b2 * i1 + b3 * i2
58      - a2 * o1 - a3 * o2;// + 1e-37;
59    in->data[i][j] = o0;
60    i2 = i1;
61    i1 = i0;
62    o2 = o1;
63    o1 = o0;
64  }
65  b->i2 = i2;
66  b->i1 = i1;
67  b->o2 = o2;
68  b->o1 = o1;
69  //}
70}
71
72void aubio_biquad_do_filtfilt(aubio_biquad_t * b, fvec_t * in, fvec_t * tmp) {
73  uint_t j,i=0;
74  uint_t length = in->length;
75  lsmp_t mir;
76  /* mirroring */
77  mir = 2*in->data[i][0];
78  b->i1 = mir - in->data[i][2];
79  b->i2 = mir - in->data[i][1];
80  /* apply filtering */
81  aubio_biquad_do(b,in);
82  /* invert  */
83  for (j = 0; j < length; j++)
84    tmp->data[i][length-j-1] = in->data[i][j];
85  /* mirror again */
86  mir = 2*tmp->data[i][0];
87  b->i1 = mir - tmp->data[i][2];
88  b->i2 = mir - tmp->data[i][1];
89  /* apply filtering */
90  aubio_biquad_do(b,tmp);
91  /* invert back */
92  for (j = 0; j < length; j++)
93    in->data[i][j] = tmp->data[i][length-j-1];
94}
95
96aubio_biquad_t * new_aubio_biquad(
97    lsmp_t b1, lsmp_t b2, lsmp_t b3, 
98    lsmp_t a2, lsmp_t a3) {
99  aubio_biquad_t * b = AUBIO_NEW(aubio_biquad_t);
100  b->a2 = a2;
101  b->a3 = a3;
102  b->b1 = b1;
103  b->b2 = b2;
104  b->b3 = b3;
105  b->i1 = 0.;
106  b->i2 = 0.;
107  b->o1 = 0.;
108  b->o2 = 0.;
109  return b;
110}
111
112void del_aubio_biquad(aubio_biquad_t * b) {
113  AUBIO_FREE(b);
114}
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