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
|
/*
* RTP JPEG-compressed video Packetizer, RFC 2435
* Copyright (c) 2012 Samuel Pitoiset
*
* 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 "libavcodec/bytestream.h"
#include "libavcodec/mjpeg.h"
#include "libavutil/intreadwrite.h"
#include "rtpenc.h"
void ff_rtp_send_jpeg(AVFormatContext *s1, const uint8_t *buf, int size)
{
RTPMuxContext *s = s1->priv_data;
const uint8_t *qtables = NULL;
int nb_qtables = 0;
uint8_t type = 1; /* default pixel format is PIX_FMT_YUVJ420P */
uint8_t w, h;
uint8_t *p;
int off = 0; /* fragment offset of the current JPEG frame */
int len;
int i;
s->buf_ptr = s->buf;
s->timestamp = s->cur_timestamp;
/* convert video pixel dimensions from pixels to blocks */
w = s1->streams[0]->codec->width >> 3;
h = s1->streams[0]->codec->height >> 3;
/* check if pixel format is not the normal 420 case */
if (s1->streams[0]->codec->pix_fmt == PIX_FMT_YUVJ422P) {
type = 0;
} else if (s1->streams[0]->codec->pix_fmt == PIX_FMT_YUVJ420P) {
type = 1;
} else {
av_log(s1, AV_LOG_ERROR, "Unsupported pixel format\n");
return;
}
/* preparse the header for getting some infos */
for (i = 0; i < size; i++) {
if (buf[i] != 0xff)
continue;
if (buf[i + 1] == DQT) {
if (buf[i + 4])
av_log(s1, AV_LOG_WARNING,
"Only 8-bit precision is supported.\n");
/* a quantization table is 64 bytes long */
nb_qtables = AV_RB16(&buf[i + 2]) / 65;
if (i + 4 + nb_qtables * 65 > size) {
av_log(s1, AV_LOG_ERROR, "Too short JPEG header. Aborted!\n");
return;
}
qtables = &buf[i + 4];
} else if (buf[i + 1] == SOF0) {
if (buf[i + 14] != 17 || buf[i + 17] != 17) {
av_log(s1, AV_LOG_ERROR,
"Only 1x1 chroma blocks are supported. Aborted!\n");
return;
}
} else if (buf[i + 1] == SOS) {
/* SOS is last marker in the header */
i += AV_RB16(&buf[i + 2]) + 2;
break;
}
}
/* skip JPEG header */
buf += i;
size -= i;
for (i = size - 2; i >= 0; i--) {
if (buf[i] == 0xff && buf[i + 1] == EOI) {
/* Remove the EOI marker */
size = i;
break;
}
}
p = s->buf_ptr;
while (size > 0) {
int hdr_size = 8;
if (off == 0 && nb_qtables)
hdr_size += 4 + 64 * nb_qtables;
/* payload max in one packet */
len = FFMIN(size, s->max_payload_size - hdr_size);
/* set main header */
bytestream_put_byte(&p, 0);
bytestream_put_be24(&p, off);
bytestream_put_byte(&p, type);
bytestream_put_byte(&p, 255);
bytestream_put_byte(&p, w);
bytestream_put_byte(&p, h);
if (off == 0 && nb_qtables) {
/* set quantization tables header */
bytestream_put_byte(&p, 0);
bytestream_put_byte(&p, 0);
bytestream_put_be16(&p, 64 * nb_qtables);
for (i = 0; i < nb_qtables; i++)
bytestream_put_buffer(&p, &qtables[65 * i + 1], 64);
}
/* copy payload data */
memcpy(p, buf, len);
/* marker bit is last packet in frame */
ff_rtp_send_data(s1, s->buf, len + hdr_size, size == len);
buf += len;
size -= len;
off += len;
p = s->buf;
}
}
|
