ffmpeg/libavcodec/vp9_parser.c

71 lines
2.0 KiB
C

/*
* VP9 compatible video decoder
*
* Copyright (C) 2013 Ronald S. Bultje <rsbultje gmail com>
* Copyright (C) 2013 Clément Bœsch <u pkh me>
*
* 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
*/
#include "libavutil/intreadwrite.h"
#include "libavcodec/get_bits.h"
#include "parser.h"
static int parse(AVCodecParserContext *ctx,
AVCodecContext *avctx,
const uint8_t **out_data, int *out_size,
const uint8_t *data, int size)
{
GetBitContext gb;
int res, profile, keyframe;
*out_data = data;
*out_size = size;
if (!size || (res = init_get_bits8(&gb, data, size)) < 0)
return size; // parsers can't return errors
get_bits(&gb, 2); // frame marker
profile = get_bits1(&gb);
profile |= get_bits1(&gb) << 1;
if (profile == 3) profile += get_bits1(&gb);
if (profile > 3)
return size;
avctx->profile = profile;
if (get_bits1(&gb)) {
keyframe = 0;
} else {
keyframe = !get_bits1(&gb);
}
if (!keyframe) {
ctx->pict_type = AV_PICTURE_TYPE_P;
ctx->key_frame = 0;
} else {
ctx->pict_type = AV_PICTURE_TYPE_I;
ctx->key_frame = 1;
}
return size;
}
AVCodecParser ff_vp9_parser = {
.codec_ids = { AV_CODEC_ID_VP9 },
.parser_parse = parse,
};