37dedc33f57dd98f75fc7051d1ce9fd9654faf65
[libav.git] / libavformat / rtpenc_mpv.c
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 Libav.
7 *
8 * Libav 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 * Libav 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 Libav; 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/mpegvideo.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_mpv_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 }