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
|
/*
* AVC helper functions for muxers
* Copyright (c) 2006 Baptiste Coudurier <baptiste.coudurier@smartjog.com>
*
* 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 "avformat.h"
#include "avio.h"
const uint8_t *ff_avc_find_startcode(const uint8_t *p, const uint8_t *end)
{
const uint8_t *a = p + 4 - ((long)p & 3);
for( end -= 3; p < a && p < end; p++ ) {
if( p[0] == 0 && p[1] == 0 && p[2] == 1 )
return p;
}
for( end -= 3; p < end; p += 4 ) {
uint32_t x = *(const uint32_t*)p;
// if( (x - 0x01000100) & (~x) & 0x80008000 ) // little endian
// if( (x - 0x00010001) & (~x) & 0x00800080 ) // big endian
if( (x - 0x01010101) & (~x) & 0x80808080 ) { // generic
if( p[1] == 0 ) {
if( p[0] == 0 && p[2] == 1 )
return p-1;
if( p[2] == 0 && p[3] == 1 )
return p;
}
if( p[3] == 0 ) {
if( p[2] == 0 && p[4] == 1 )
return p+1;
if( p[4] == 0 && p[5] == 1 )
return p+2;
}
}
}
for( end += 3; p < end; p++ ) {
if( p[0] == 0 && p[1] == 0 && p[2] == 1 )
return p;
}
return end + 3;
}
int ff_avc_parse_nal_units(ByteIOContext *pb, const uint8_t *buf_in, int size)
{
const uint8_t *p = buf_in;
const uint8_t *end = p + size;
const uint8_t *nal_start, *nal_end;
size = 0;
nal_start = ff_avc_find_startcode(p, end);
while (nal_start < end) {
while(!*(nal_start++));
nal_end = ff_avc_find_startcode(nal_start, end);
put_be32(pb, nal_end - nal_start);
put_buffer(pb, nal_start, nal_end - nal_start);
size += 4 + nal_end - nal_start;
nal_start = nal_end;
}
return size;
}
int ff_avc_parse_nal_units_buf(const uint8_t *buf_in, uint8_t **buf, int *size)
{
ByteIOContext *pb;
int ret = url_open_dyn_buf(&pb);
if(ret < 0)
return ret;
ff_avc_parse_nal_units(pb, buf_in, *size);
av_freep(buf);
*size = url_close_dyn_buf(pb, buf);
return 0;
}
int ff_isom_write_avcc(ByteIOContext *pb, const uint8_t *data, int len)
{
if (len > 6) {
/* check for h264 start code */
if (AV_RB32(data) == 0x00000001 ||
AV_RB24(data) == 0x000001) {
uint8_t *buf=NULL, *end, *start;
uint32_t sps_size=0, pps_size=0;
uint8_t *sps=0, *pps=0;
int ret = ff_avc_parse_nal_units_buf(data, &buf, &len);
if (ret < 0)
return ret;
start = buf;
end = buf + len;
/* look for sps and pps */
while (buf < end) {
unsigned int size;
uint8_t nal_type;
size = AV_RB32(buf);
nal_type = buf[4] & 0x1f;
if (nal_type == 7) { /* SPS */
sps = buf + 4;
sps_size = size;
} else if (nal_type == 8) { /* PPS */
pps = buf + 4;
pps_size = size;
}
buf += size + 4;
}
assert(sps);
assert(pps);
put_byte(pb, 1); /* version */
put_byte(pb, sps[1]); /* profile */
put_byte(pb, sps[2]); /* profile compat */
put_byte(pb, sps[3]); /* level */
put_byte(pb, 0xff); /* 6 bits reserved (111111) + 2 bits nal size length - 1 (11) */
put_byte(pb, 0xe1); /* 3 bits reserved (111) + 5 bits number of sps (00001) */
put_be16(pb, sps_size);
put_buffer(pb, sps, sps_size);
put_byte(pb, 1); /* number of pps */
put_be16(pb, pps_size);
put_buffer(pb, pps, pps_size);
av_free(start);
} else {
put_buffer(pb, data, len);
}
}
return 0;
}
|
