Line data Source code
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 0 : void ff_rtp_send_mpegvideo(AVFormatContext *s1, const uint8_t *buf1, int size)
30 : {
31 0 : RTPMuxContext *s = s1->priv_data;
32 : int len, h, max_packet_size;
33 : uint8_t *q;
34 0 : const uint8_t *end = buf1 + size;
35 : int begin_of_slice, end_of_slice, frame_type, temporal_reference;
36 :
37 0 : max_packet_size = s->max_payload_size;
38 0 : begin_of_slice = 1;
39 0 : end_of_slice = 0;
40 0 : frame_type = 0;
41 0 : temporal_reference = 0;
42 :
43 0 : while (size > 0) {
44 : int begin_of_sequence;
45 :
46 0 : begin_of_sequence = 0;
47 0 : len = max_packet_size - 4;
48 :
49 0 : if (len >= size) {
50 0 : len = size;
51 0 : end_of_slice = 1;
52 : } else {
53 : const uint8_t *r, *r1;
54 : int start_code;
55 :
56 0 : r1 = buf1;
57 : while (1) {
58 0 : start_code = -1;
59 0 : r = avpriv_find_start_code(r1, end, &start_code);
60 0 : if((start_code & 0xFFFFFF00) == 0x100) {
61 : /* New start code found */
62 0 : if (start_code == 0x100) {
63 0 : frame_type = (r[1] & 0x38) >> 3;
64 0 : temporal_reference = (int)r[0] << 2 | r[1] >> 6;
65 : }
66 0 : if (start_code == 0x1B8) {
67 0 : begin_of_sequence = 1;
68 : }
69 :
70 0 : if (r - buf1 - 4 <= len) {
71 : /* The current slice fits in the packet */
72 0 : if (begin_of_slice == 0) {
73 : /* no slice at the beginning of the packet... */
74 0 : end_of_slice = 1;
75 0 : len = r - buf1 - 4;
76 0 : break;
77 : }
78 0 : r1 = r;
79 : } else {
80 0 : if ((r1 - buf1 > 4) && (r - r1 < max_packet_size)) {
81 0 : len = r1 - buf1 - 4;
82 0 : end_of_slice = 1;
83 : }
84 0 : break;
85 : }
86 : } else {
87 0 : break;
88 : }
89 : }
90 : }
91 :
92 0 : h = 0;
93 0 : h |= temporal_reference << 16;
94 0 : h |= begin_of_sequence << 13;
95 0 : h |= begin_of_slice << 12;
96 0 : h |= end_of_slice << 11;
97 0 : h |= frame_type << 8;
98 :
99 0 : q = s->buf;
100 0 : *q++ = h >> 24;
101 0 : *q++ = h >> 16;
102 0 : *q++ = h >> 8;
103 0 : *q++ = h;
104 :
105 0 : memcpy(q, buf1, len);
106 0 : q += len;
107 :
108 : /* 90kHz time stamp */
109 0 : s->timestamp = s->cur_timestamp;
110 0 : ff_rtp_send_data(s1, s->buf, q - s->buf, (len == size));
111 :
112 0 : buf1 += len;
113 0 : size -= len;
114 0 : begin_of_slice = end_of_slice;
115 0 : end_of_slice = 0;
116 : }
117 0 : }
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