FFmpeg
vp9_parser.c
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1 /*
2  * VP9 compatible video decoder
3  *
4  * Copyright (C) 2013 Ronald S. Bultje <rsbultje gmail com>
5  * Copyright (C) 2013 Clément Bœsch <u pkh me>
6  *
7  * This file is part of FFmpeg.
8  *
9  * FFmpeg is free software; you can redistribute it and/or
10  * modify it under the terms of the GNU Lesser General Public
11  * License as published by the Free Software Foundation; either
12  * version 2.1 of the License, or (at your option) any later version.
13  *
14  * FFmpeg is distributed in the hope that it will be useful,
15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
17  * Lesser General Public License for more details.
18  *
19  * You should have received a copy of the GNU Lesser General Public
20  * License along with FFmpeg; if not, write to the Free Software
21  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
22  */
23 
24 #include "libavutil/intreadwrite.h"
25 #include "libavcodec/get_bits.h"
26 #include "parser.h"
27 
29  AVCodecContext *avctx,
30  const uint8_t **out_data, int *out_size,
31  const uint8_t *data, int size)
32 {
33  GetBitContext gb;
34  int res, profile, keyframe;
35 
36  *out_data = data;
37  *out_size = size;
38 
39  if (!size || (res = init_get_bits8(&gb, data, size)) < 0)
40  return size; // parsers can't return errors
41  get_bits(&gb, 2); // frame marker
42  profile = get_bits1(&gb);
43  profile |= get_bits1(&gb) << 1;
44  if (profile == 3) profile += get_bits1(&gb);
45  if (profile > 3)
46  return size;
47 
48  avctx->profile = profile;
49 
50  if (get_bits1(&gb)) {
51  keyframe = 0;
52  } else {
53  keyframe = !get_bits1(&gb);
54  }
55 
56  if (!keyframe) {
58  ctx->key_frame = 0;
59  } else {
61  ctx->key_frame = 1;
62  }
63 
64  return size;
65 }
66 
69  .parser_parse = parse,
70 };
AVCodecParser ff_vp9_parser
Definition: vp9_parser.c:67
ptrdiff_t const GLvoid * data
Definition: opengl_enc.c:100
static unsigned int get_bits(GetBitContext *s, int n)
Read 1-25 bits.
Definition: get_bits.h:379
int codec_ids[5]
Definition: avcodec.h:5290
int out_size
Definition: movenc.c:55
int profile
profile
Definition: avcodec.h:2904
static int parse(AVCodecParserContext *ctx, AVCodecContext *avctx, const uint8_t **out_data, int *out_size, const uint8_t *data, int size)
Definition: vp9_parser.c:28
uint8_t
bitstream reader API header.
ptrdiff_t size
Definition: opengl_enc.c:100
AVFormatContext * ctx
Definition: movenc.c:48
static int init_get_bits8(GetBitContext *s, const uint8_t *buffer, int byte_size)
Initialize GetBitContext.
Definition: get_bits.h:677
main external API structure.
Definition: avcodec.h:1571
static unsigned int get_bits1(GetBitContext *s)
Definition: get_bits.h:498
mfxU16 profile
Definition: qsvenc.c:44
int key_frame
Set by parser to 1 for key frames and 0 for non-key frames.
Definition: avcodec.h:5171
Predicted.
Definition: avutil.h:275