yuzu/externals/ffmpeg/libavcodec/dpx_parser.c
2021-02-09 04:25:58 +01:00

117 lines
3.2 KiB
C
Executable File

/*
* DPX parser
* Copyright (c) 2013 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
* DPX parser
*/
#include "libavutil/bswap.h"
#include "libavutil/common.h"
#include "parser.h"
typedef struct DPXParseContext {
ParseContext pc;
uint32_t index;
uint32_t fsize;
uint32_t remaining_size;
int is_be;
} DPXParseContext;
static int dpx_parse(AVCodecParserContext *s, AVCodecContext *avctx,
const uint8_t **poutbuf, int *poutbuf_size,
const uint8_t *buf, int buf_size)
{
DPXParseContext *d = s->priv_data;
uint32_t state = d->pc.state;
int next = END_NOT_FOUND;
int i = 0;
s->pict_type = AV_PICTURE_TYPE_I;
*poutbuf_size = 0;
if (buf_size == 0)
next = 0;
if (!d->pc.frame_start_found) {
for (; i < buf_size; i++) {
state = (state << 8) | buf[i];
if (state == MKBETAG('S','D','P','X') ||
state == MKTAG('S','D','P','X')) {
d->pc.frame_start_found = 1;
d->is_be = state == MKBETAG('S','D','P','X');
d->index = 0;
break;
}
}
d->pc.state = state;
} else {
if (d->remaining_size) {
i = FFMIN(d->remaining_size, buf_size);
d->remaining_size -= i;
if (d->remaining_size)
goto flush;
}
}
for (; d->pc.frame_start_found && i < buf_size; i++) {
d->pc.state = (d->pc.state << 8) | buf[i];
d->index++;
if (d->index == 17) {
d->fsize = d->is_be ? d->pc.state : av_bswap32(d->pc.state);
if (d->fsize <= 1664) {
d->pc.frame_start_found = 0;
goto flush;
}
if (d->fsize > buf_size - i + 19)
d->remaining_size = d->fsize - buf_size + i - 19;
else
i += d->fsize - 19;
break;
} else if (d->index > 17) {
if (d->pc.state == MKBETAG('S','D','P','X') ||
d->pc.state == MKTAG('S','D','P','X')) {
next = i - 3;
break;
}
}
}
flush:
if (ff_combine_frame(&d->pc, next, &buf, &buf_size) < 0)
return buf_size;
d->pc.frame_start_found = 0;
*poutbuf = buf;
*poutbuf_size = buf_size;
return next;
}
AVCodecParser ff_dpx_parser = {
.codec_ids = { AV_CODEC_ID_DPX },
.priv_data_size = sizeof(DPXParseContext),
.parser_parse = dpx_parse,
.parser_close = ff_parse_close,
};