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/*
* TAK parser
* Copyright (c) 2012 Michael Niedermayer
*
* This file is part of Libav.
*
* Libav 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.
*
* Libav 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 Libav; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
/**
* @file
* TAK parser
**/
#include "tak.h"
#include "parser.h"
typedef struct TAKParseContext {
ParseContext pc;
TAKStreamInfo ti;
int index;
} TAKParseContext;
static av_cold int tak_init(AVCodecParserContext *s)
{
ff_tak_init_crc();
return 0;
}
static int tak_parse(AVCodecParserContext *s, AVCodecContext *avctx,
const uint8_t **poutbuf, int *poutbuf_size,
const uint8_t *buf, int buf_size)
{
TAKParseContext *t = s->priv_data;
ParseContext *pc = &t->pc;
int next = END_NOT_FOUND;
GetBitContext gb;
int consumed = 0;
int needed = buf_size ? TAK_MAX_FRAME_HEADER_BYTES : 8;
if (s->flags & PARSER_FLAG_COMPLETE_FRAMES) {
TAKStreamInfo ti;
init_get_bits(&gb, buf, buf_size);
if (!ff_tak_decode_frame_header(avctx, &gb, &ti, 127))
s->duration = t->ti.last_frame_samples ? t->ti.last_frame_samples
: t->ti.frame_samples;
*poutbuf = buf;
*poutbuf_size = buf_size;
return buf_size;
}
while (buf_size || t->index + needed <= pc->index) {
if (buf_size && t->index + TAK_MAX_FRAME_HEADER_BYTES > pc->index) {
int tmp_buf_size = FFMIN(2 * TAK_MAX_FRAME_HEADER_BYTES,
buf_size);
const uint8_t *tmp_buf = buf;
ff_combine_frame(pc, END_NOT_FOUND, &tmp_buf, &tmp_buf_size);
consumed += tmp_buf_size;
buf += tmp_buf_size;
buf_size -= tmp_buf_size;
}
for (; t->index + needed <= pc->index; t->index++)
if (pc->buffer[t->index] == 0xFF &&
pc->buffer[t->index + 1] == 0xA0) {
TAKStreamInfo ti;
init_get_bits(&gb, pc->buffer + t->index,
8 * (pc->index - t->index));
if (!ff_tak_decode_frame_header(avctx, &gb,
pc->frame_start_found ? &ti
: &t->ti,
127) &&
!ff_tak_check_crc(pc->buffer + t->index,
get_bits_count(&gb) / 8)) {
if (!pc->frame_start_found) {
pc->frame_start_found = 1;
s->duration = t->ti.last_frame_samples ?
t->ti.last_frame_samples :
t->ti.frame_samples;
} else {
pc->frame_start_found = 0;
next = t->index - pc->index;
t->index = 0;
goto found;
}
}
}
}
found:
if (consumed && !buf_size && next == END_NOT_FOUND ||
ff_combine_frame(pc, next, &buf, &buf_size) < 0) {
*poutbuf = NULL;
*poutbuf_size = 0;
return buf_size + consumed;
}
if (next != END_NOT_FOUND) {
next += consumed;
pc->overread = FFMAX(0, -next);
}
*poutbuf = buf;
*poutbuf_size = buf_size;
return next;
}
AVCodecParser ff_tak_parser = {
.codec_ids = { AV_CODEC_ID_TAK },
.priv_data_size = sizeof(TAKParseContext),
.parser_init = tak_init,
.parser_parse = tak_parse,
.parser_close = ff_parse_close,
};
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