ffmpeg/libavcodec/hdr_parser.c

80 lines
2.2 KiB
C

/*
* Radiance HDR parser
* Copyright (c) 2022 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
* Radiance HDR parser
*/
#include "libavutil/intreadwrite.h"
#include "parser.h"
typedef struct HDRParseContext {
ParseContext pc;
} HDRParseContext;
static int hdr_parse(AVCodecParserContext *s, AVCodecContext *avctx,
const uint8_t **poutbuf, int *poutbuf_size,
const uint8_t *buf, int buf_size)
{
HDRParseContext *ipc = s->priv_data;
uint64_t state = ipc->pc.state64;
int next = END_NOT_FOUND, i = 0;
*poutbuf_size = 0;
*poutbuf = NULL;
if (s->flags & PARSER_FLAG_COMPLETE_FRAMES) {
next = buf_size;
} else {
for (; i < buf_size; i++) {
state = (state << 8) | buf[i];
if (state == AV_RB64("ADIANCE\n") && (i > 10 || ipc->pc.index > 10)) {
next = i - 10;
break;
}
}
ipc->pc.state64 = state;
if (ff_combine_frame(&ipc->pc, next, &buf, &buf_size) < 0) {
*poutbuf = NULL;
*poutbuf_size = 0;
return buf_size;
}
}
*poutbuf = buf;
*poutbuf_size = buf_size;
s->pict_type = AV_PICTURE_TYPE_I;
s->key_frame = 1;
s->duration = 1;
return next;
}
const AVCodecParser ff_hdr_parser = {
.codec_ids = { AV_CODEC_ID_RADIANCE_HDR },
.priv_data_size = sizeof(HDRParseContext),
.parser_parse = hdr_parse,
.parser_close = ff_parse_close,
};