1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
|
/*
* 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"
typedef struct VP9ParseContext {
int n_frames; // 1-8
int size[8];
int marker_size;
int64_t pts;
} VP9ParseContext;
static int parse_frame(AVCodecParserContext *ctx, const uint8_t *buf, int size)
{
VP9ParseContext *s = ctx->priv_data;
GetBitContext gb;
int res, profile, keyframe, invisible;
if ((res = init_get_bits8(&gb, buf, size)) < 0)
return res;
get_bits(&gb, 2); // frame marker
profile = get_bits1(&gb);
profile |= get_bits1(&gb) << 1;
if (profile == 3) profile += get_bits1(&gb);
if (get_bits1(&gb)) {
keyframe = 0;
invisible = 0;
} else {
keyframe = !get_bits1(&gb);
invisible = !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;
}
if (!invisible) {
if (ctx->pts == AV_NOPTS_VALUE)
ctx->pts = s->pts;
s->pts = AV_NOPTS_VALUE;
} else {
s->pts = ctx->pts;
ctx->pts = AV_NOPTS_VALUE;
}
return 0;
}
static int parse(AVCodecParserContext *ctx,
AVCodecContext *avctx,
const uint8_t **out_data, int *out_size,
const uint8_t *data, int size)
{
VP9ParseContext *s = ctx->priv_data;
int full_size = size;
int marker;
if (size <= 0) {
*out_size = 0;
*out_data = data;
return 0;
}
if (s->n_frames > 0) {
int i;
int size_sum = 0;
for (i = 0; i < s->n_frames ;i++)
size_sum += s->size[i];
size_sum += s->marker_size;
if (size_sum != size) {
av_log(avctx, AV_LOG_ERROR, "Inconsistent input frame sizes %d %d\n",
size_sum, size);
s->n_frames = 0;
}
}
if (s->n_frames > 0) {
*out_data = data;
*out_size = s->size[--s->n_frames];
parse_frame(ctx, *out_data, *out_size);
return s->n_frames > 0 ? *out_size : size /* i.e. include idx tail */;
}
marker = data[size - 1];
if ((marker & 0xe0) == 0xc0) {
int nbytes = 1 + ((marker >> 3) & 0x3);
int n_frames = 1 + (marker & 0x7), idx_sz = 2 + n_frames * nbytes;
if (size >= idx_sz && data[size - idx_sz] == marker) {
const uint8_t *idx = data + size + 1 - idx_sz;
int first = 1;
switch (nbytes) {
#define case_n(a, rd) \
case a: \
while (n_frames--) { \
unsigned sz = rd; \
idx += a; \
if (sz > size) { \
s->n_frames = 0; \
*out_size = size; \
*out_data = data; \
av_log(avctx, AV_LOG_ERROR, \
"Superframe packet size too big: %u > %d\n", \
sz, size); \
return full_size; \
} \
if (first) { \
first = 0; \
*out_data = data; \
*out_size = sz; \
s->n_frames = n_frames; \
} else { \
s->size[n_frames] = sz; \
} \
data += sz; \
size -= sz; \
} \
s->marker_size = size; \
parse_frame(ctx, *out_data, *out_size); \
return *out_size
case_n(1, *idx);
case_n(2, AV_RL16(idx));
case_n(3, AV_RL24(idx));
case_n(4, AV_RL32(idx));
}
}
}
*out_data = data;
*out_size = size;
parse_frame(ctx, data, size);
return size;
}
AVCodecParser ff_vp9_parser = {
.codec_ids = { AV_CODEC_ID_VP9 },
.priv_data_size = sizeof(VP9ParseContext),
.parser_parse = parse,
};
|
