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; }