mirror of
https://github.com/FFmpeg/FFmpeg.git
synced 2024-12-07 11:13:41 +02:00
106 lines
2.9 KiB
C
106 lines
2.9 KiB
C
/*
|
|
* CRI parser
|
|
* Copyright (c) 2021 Paul B Mahol
|
|
*
|
|
* 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
|
|
* CRI parser
|
|
*/
|
|
|
|
#include "libavutil/bswap.h"
|
|
#include "libavutil/common.h"
|
|
|
|
#include "parser.h"
|
|
|
|
typedef struct CRIParser {
|
|
ParseContext pc;
|
|
int count;
|
|
int chunk;
|
|
int read_bytes;
|
|
int skip_bytes;
|
|
} CRIParser;
|
|
|
|
#define KEY (((uint64_t)'\1' << 56) | ((uint64_t)'\0' << 48) | \
|
|
((uint64_t)'\0' << 40) | ((uint64_t)'\0' << 32) | \
|
|
((uint64_t)'\4' << 24) | ((uint64_t)'\0' << 16) | \
|
|
((uint64_t)'\0' << 8) | ((uint64_t)'\0' << 0))
|
|
|
|
static int cri_parse(AVCodecParserContext *s, AVCodecContext *avctx,
|
|
const uint8_t **poutbuf, int *poutbuf_size,
|
|
const uint8_t *buf, int buf_size)
|
|
{
|
|
CRIParser *bpc = s->priv_data;
|
|
uint64_t state = bpc->pc.state64;
|
|
int next = END_NOT_FOUND, i = 0;
|
|
|
|
s->pict_type = AV_PICTURE_TYPE_I;
|
|
s->key_frame = 1;
|
|
s->duration = 1;
|
|
|
|
*poutbuf_size = 0;
|
|
*poutbuf = NULL;
|
|
|
|
for (; i < buf_size; i++) {
|
|
state = (state << 8) | buf[i];
|
|
bpc->read_bytes++;
|
|
|
|
if (bpc->skip_bytes > 0) {
|
|
bpc->skip_bytes--;
|
|
if (bpc->skip_bytes == 0)
|
|
bpc->read_bytes = 0;
|
|
} else {
|
|
if (state != KEY)
|
|
continue;
|
|
}
|
|
|
|
if (bpc->skip_bytes == 0 && bpc->read_bytes >= 8) {
|
|
bpc->skip_bytes = av_bswap32(state & 0xFFFFFFFF);
|
|
bpc->chunk = state >> 32;
|
|
bpc->read_bytes = 0;
|
|
bpc->count++;
|
|
}
|
|
|
|
if (bpc->chunk == 0x01000000 && bpc->skip_bytes == 4 &&
|
|
bpc->read_bytes == 0 && bpc->count > 1) {
|
|
next = i - 7;
|
|
break;
|
|
}
|
|
}
|
|
|
|
bpc->pc.state64 = state;
|
|
if (ff_combine_frame(&bpc->pc, next, &buf, &buf_size) < 0) {
|
|
*poutbuf = NULL;
|
|
*poutbuf_size = 0;
|
|
return buf_size;
|
|
}
|
|
|
|
*poutbuf = buf;
|
|
*poutbuf_size = buf_size;
|
|
|
|
return next;
|
|
}
|
|
|
|
AVCodecParser ff_cri_parser = {
|
|
.codec_ids = { AV_CODEC_ID_CRI },
|
|
.priv_data_size = sizeof(CRIParser),
|
|
.parser_parse = cri_parse,
|
|
.parser_close = ff_parse_close,
|
|
};
|