ref: 0141f233364b96bee00bee7463c494a981f50e55
dir: /src/remix.c/
/*
* Effect: remix
* Copyright (c) 2008 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 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,
* Fifth Floor, 51 Franklin Street, Boston, MA 02111-1301, USA.
*/
#include "sox_i.h"
#include <math.h>
#include <string.h>
typedef struct remix
{
enum {semi, automatic, manual} mode;
unsigned num_out_channels, min_in_channels;
struct {
char * str; /* Command-line argument to parse for this out_spec */
unsigned num_in_channels;
struct in_spec {
unsigned channel_num;
double multiplier;
} * in_specs;
} * out_specs;
} * remix_t;
assert_static(sizeof(struct remix) <= SOX_MAX_EFFECT_PRIVSIZE,
/* else */ remix_PRIVSIZE_too_big);
#define PARSE(SEP, SCAN, VAR, MIN, SEPARATORS) do {\
end = strpbrk(text, SEPARATORS); \
if (end == text) \
SEP = *text++; \
else { \
SEP = (SEPARATORS)[strlen(SEPARATORS) - 1]; \
n = sscanf(text, SCAN"%c", &VAR, &SEP); \
if (VAR < MIN || (n == 2 && !strchr(SEPARATORS, SEP))) \
return sox_usage(effp); \
text = end? end + 1 : text + strlen(text); \
} \
} while (0)
static int parse(sox_effect_t * effp, char * * argv, unsigned channels)
{
remix_t p = (remix_t) effp->priv;
unsigned i, j;
p->min_in_channels = 0;
for (i = 0; i < p->num_out_channels; ++i) {
sox_bool mul_spec = sox_false;
char * text, * end;
if (argv) /* 1st parse only */
p->out_specs[i].str = xstrdup(argv[i]);
for (j = 0, text = p->out_specs[i].str; *text;) {
static char const separators[] = "-vpi,";
char sep1, sep2;
int chan1 = 1, chan2 = channels, n;
double multiplier = HUGE_VAL;
PARSE(sep1, "%i", chan1, 0, separators);
if (!chan1) {
if (j || *text)
return sox_usage(effp);
continue;
}
if (sep1 == '-')
PARSE(sep1, "%i", chan2, 0, separators + 1);
else chan2 = chan1;
if (sep1 != ',') {
multiplier = sep1 == 'v' ? 1 : 0;
PARSE(sep2, "%lf", multiplier, -HUGE_VAL, separators + 4);
if (sep1 != 'v')
multiplier = (sep1 == 'p'? 1 : -1) * dB_to_linear(multiplier);
mul_spec = sox_true;
}
if (chan2 < chan1) {int t = chan1; chan1 = chan2; chan2 = t;}
p->out_specs[i].in_specs = xrealloc(p->out_specs[i].in_specs,
(j + chan2 - chan1 + 1) * sizeof(*p->out_specs[i].in_specs));
while (chan1 <= chan2) {
p->out_specs[i].in_specs[j].channel_num = chan1++ - 1;
p->out_specs[i].in_specs[j++].multiplier = multiplier;
}
p->min_in_channels = max(p->min_in_channels, (unsigned)chan2);
}
p->out_specs[i].num_in_channels = j;
for (j = 0; j < p->out_specs[i].num_in_channels; ++j)
if (p->out_specs[i].in_specs[j].multiplier == HUGE_VAL)
p->out_specs[i].in_specs[j].multiplier = (p->mode == automatic || (p->mode == semi && !mul_spec)) ? 1. / p->out_specs[i].num_in_channels : 1;
}
effp->out_signal.channels = p->num_out_channels;
return SOX_SUCCESS;
}
static int create(sox_effect_t * effp, int argc, char * * argv)
{
remix_t p = (remix_t) effp->priv;
if (argc && !strcmp(*argv, "-m")) p->mode = manual , ++argv, --argc;
if (argc && !strcmp(*argv, "-a")) p->mode = automatic, ++argv, --argc;
p->out_specs = xcalloc(p->num_out_channels = argc, sizeof(*p->out_specs));
return parse(effp, argv, 1); /* No channels yet; parse with dummy */
}
static int start(sox_effect_t * effp)
{
remix_t p = (remix_t) effp->priv;
parse(effp, NULL, effp->in_signal.channels);
if (effp->in_signal.channels < p->min_in_channels) {
sox_fail("too few input channels");
return SOX_EOF;
}
return SOX_SUCCESS;
}
static int flow(sox_effect_t * effp, const sox_sample_t * ibuf,
sox_sample_t * obuf, sox_size_t * isamp, sox_size_t * osamp)
{
remix_t p = (remix_t) effp->priv;
unsigned i, j, len;
len = min(*isamp / effp->in_signal.channels, *osamp / effp->out_signal.channels);
*isamp = len * effp->in_signal.channels;
*osamp = len * effp->out_signal.channels;
for (; len--; ibuf += effp->in_signal.channels) for (j = 0; j < effp->out_signal.channels; j++) {
double out = 0;
for (i = 0; i < p->out_specs[j].num_in_channels; i++)
out += ibuf[p->out_specs[j].in_specs[i].channel_num] * p->out_specs[j].in_specs[i].multiplier;
*obuf++ = SOX_ROUND_CLIP_COUNT(out, effp->clips);
}
return SOX_SUCCESS;
}
static int kill(sox_effect_t * effp)
{
remix_t p = (remix_t) effp->priv;
unsigned i;
for (i = 0; i < p->num_out_channels; ++i) {
free(p->out_specs[i].str);
free(p->out_specs[i].in_specs);
}
free(p->out_specs);
return SOX_SUCCESS;
}
sox_effect_handler_t const * sox_remix_effect_fn(void)
{
static sox_effect_handler_t handler = {
"remix", "<0|in-chan[v|d|i volume]{,in-chan[v|d|i volume]}>",
SOX_EFF_MCHAN | SOX_EFF_CHAN,
create, start, flow, NULL, NULL, kill
};
return &handler;
}