blob: 4b45f5177215d04dfc274ddc20bc11f6fd0e5c22
1 | /* |
2 | * RTP packetization for MPEG video |
3 | * Copyright (c) 2002 Fabrice Bellard |
4 | * Copyright (c) 2007 Luca Abeni |
5 | * |
6 | * This file is part of FFmpeg. |
7 | * |
8 | * FFmpeg is free software; you can redistribute it and/or |
9 | * modify it under the terms of the GNU Lesser General Public |
10 | * License as published by the Free Software Foundation; either |
11 | * version 2.1 of the License, or (at your option) any later version. |
12 | * |
13 | * FFmpeg is distributed in the hope that it will be useful, |
14 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
15 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
16 | * Lesser General Public License for more details. |
17 | * |
18 | * You should have received a copy of the GNU Lesser General Public |
19 | * License along with FFmpeg; if not, write to the Free Software |
20 | * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA |
21 | */ |
22 | |
23 | #include "libavcodec/internal.h" |
24 | #include "avformat.h" |
25 | #include "rtpenc.h" |
26 | |
27 | /* NOTE: a single frame must be passed with sequence header if |
28 | needed. XXX: use slices. */ |
29 | void ff_rtp_send_mpegvideo(AVFormatContext *s1, const uint8_t *buf1, int size) |
30 | { |
31 | RTPMuxContext *s = s1->priv_data; |
32 | int len, h, max_packet_size; |
33 | uint8_t *q; |
34 | const uint8_t *end = buf1 + size; |
35 | int begin_of_slice, end_of_slice, frame_type, temporal_reference; |
36 | |
37 | max_packet_size = s->max_payload_size; |
38 | begin_of_slice = 1; |
39 | end_of_slice = 0; |
40 | frame_type = 0; |
41 | temporal_reference = 0; |
42 | |
43 | while (size > 0) { |
44 | int begin_of_sequence; |
45 | |
46 | begin_of_sequence = 0; |
47 | len = max_packet_size - 4; |
48 | |
49 | if (len >= size) { |
50 | len = size; |
51 | end_of_slice = 1; |
52 | } else { |
53 | const uint8_t *r, *r1; |
54 | int start_code; |
55 | |
56 | r1 = buf1; |
57 | while (1) { |
58 | start_code = -1; |
59 | r = avpriv_find_start_code(r1, end, &start_code); |
60 | if((start_code & 0xFFFFFF00) == 0x100) { |
61 | /* New start code found */ |
62 | if (start_code == 0x100) { |
63 | frame_type = (r[1] & 0x38) >> 3; |
64 | temporal_reference = (int)r[0] << 2 | r[1] >> 6; |
65 | } |
66 | if (start_code == 0x1B8) { |
67 | begin_of_sequence = 1; |
68 | } |
69 | |
70 | if (r - buf1 - 4 <= len) { |
71 | /* The current slice fits in the packet */ |
72 | if (begin_of_slice == 0) { |
73 | /* no slice at the beginning of the packet... */ |
74 | end_of_slice = 1; |
75 | len = r - buf1 - 4; |
76 | break; |
77 | } |
78 | r1 = r; |
79 | } else { |
80 | if ((r1 - buf1 > 4) && (r - r1 < max_packet_size)) { |
81 | len = r1 - buf1 - 4; |
82 | end_of_slice = 1; |
83 | } |
84 | break; |
85 | } |
86 | } else { |
87 | break; |
88 | } |
89 | } |
90 | } |
91 | |
92 | h = 0; |
93 | h |= temporal_reference << 16; |
94 | h |= begin_of_sequence << 13; |
95 | h |= begin_of_slice << 12; |
96 | h |= end_of_slice << 11; |
97 | h |= frame_type << 8; |
98 | |
99 | q = s->buf; |
100 | *q++ = h >> 24; |
101 | *q++ = h >> 16; |
102 | *q++ = h >> 8; |
103 | *q++ = h; |
104 | |
105 | memcpy(q, buf1, len); |
106 | q += len; |
107 | |
108 | /* 90kHz time stamp */ |
109 | s->timestamp = s->cur_timestamp; |
110 | ff_rtp_send_data(s1, s->buf, q - s->buf, (len == size)); |
111 | |
112 | buf1 += len; |
113 | size -= len; |
114 | begin_of_slice = end_of_slice; |
115 | end_of_slice = 0; |
116 | } |
117 | } |
118 |