1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
|
/* libSoX effect: divide Copyright (c) 2009 robs@users.sourceforge.net
*
* This library is free software; you can redistribute it and/or modify it
* under the terms of the GNU Lesser General Public License as published by
* the Free Software Foundation; either version 2.1 of the License, or (at
* your option) any later version.
*
* This library 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 Lesser
* General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public License
* along with this library; if not, write to the Free Software Foundation,
* Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
/* This is W.I.P. hence marked SOX_EFF_ALPHA for now.
* Needs better handling of when the divisor approaches or is zero; some
* sort of interpolation of the output values perhaps.
*/
#include "sox_i.h"
#include <string.h>
typedef struct {
sox_sample_t * last;
} priv_t;
static int start(sox_effect_t * effp)
{
priv_t * p = (priv_t *)effp->priv;
p->last = lsx_calloc(effp->in_signal.channels, sizeof(*p->last));
return SOX_SUCCESS;
}
static int flow(sox_effect_t * effp, const sox_sample_t * ibuf,
sox_sample_t * obuf, size_t * isamp, size_t * osamp)
{
priv_t * p = (priv_t *)effp->priv;
size_t i, len = min(*isamp, *osamp) / effp->in_signal.channels;
*osamp = *isamp = len * effp->in_signal.channels;
while (len--) {
double divisor = *obuf++ = *ibuf++;
if (divisor) {
double out, mult = 1. / SOX_SAMPLE_TO_FLOAT_64BIT(divisor,);
for (i = 1; i < effp->in_signal.channels; ++i) {
out = *ibuf++ * mult;
p->last[i] = *obuf++ = SOX_ROUND_CLIP_COUNT(out, effp->clips);
}
}
else for (i = 1; i < effp->in_signal.channels; ++i, ++ibuf)
*obuf++ = p->last[i];
}
return SOX_SUCCESS;
}
static int stop(sox_effect_t * effp)
{
priv_t * p = (priv_t *)effp->priv;
free(p->last);
return SOX_SUCCESS;
}
sox_effect_handler_t const * lsx_divide_effect_fn(void)
{
static sox_effect_handler_t handler = {
"divide", NULL, SOX_EFF_MCHAN | SOX_EFF_GAIN | SOX_EFF_ALPHA,
NULL, start, flow, NULL, stop, NULL, sizeof(priv_t)
};
return &handler;
}
|
