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/*
* Copyright (c) 2012 Justin Ruggles
*
* This file is part of FFmpeg.
*
* FFmpeg 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.
*
* FFmpeg 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 FFmpeg; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
/**
* @file
* GSM audio parser
*
* Splits packets into individual blocks.
*/
#include "libavutil/avassert.h"
#include "parser.h"
#include "gsm.h"
typedef struct GSMParseContext {
ParseContext pc;
int block_size;
int duration;
int remaining;
} GSMParseContext;
static int gsm_parse(AVCodecParserContext *s1, AVCodecContext *avctx,
const uint8_t **poutbuf, int *poutbuf_size,
const uint8_t *buf, int buf_size)
{
GSMParseContext *s = s1->priv_data;
ParseContext *pc = &s->pc;
int next;
if (!s->block_size) {
switch (avctx->codec_id) {
case AV_CODEC_ID_GSM:
s->block_size = GSM_BLOCK_SIZE;
s->duration = GSM_FRAME_SIZE;
break;
case AV_CODEC_ID_GSM_MS:
s->block_size = avctx->block_align ? avctx->block_align
: GSM_MS_BLOCK_SIZE;
s->duration = GSM_FRAME_SIZE * 2;
break;
default:
av_assert0(0);
}
}
if (!s->remaining)
s->remaining = s->block_size;
if (s->remaining <= buf_size) {
next = s->remaining;
s->remaining = 0;
} else {
next = END_NOT_FOUND;
s->remaining -= buf_size;
}
if (ff_combine_frame(pc, next, &buf, &buf_size) < 0 || !buf_size) {
*poutbuf = NULL;
*poutbuf_size = 0;
return buf_size;
}
s1->duration = s->duration;
*poutbuf = buf;
*poutbuf_size = buf_size;
return next;
}
const AVCodecParser ff_gsm_parser = {
.codec_ids = { AV_CODEC_ID_GSM, AV_CODEC_ID_GSM_MS },
.priv_data_size = sizeof(GSMParseContext),
.parser_parse = gsm_parse,
.parser_close = ff_parse_close,
};
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