rtpenc: Add support for mp4 format h264
[libav.git] / libavformat / rtpenc_h264.c
1 /*
2 * RTP packetization for H.264 (RFC3984)
3 * Copyright (c) 2008 Luca Abeni
4 *
5 * This file is part of Libav.
6 *
7 * Libav is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU Lesser General Public
9 * License as published by the Free Software Foundation; either
10 * version 2.1 of the License, or (at your option) any later version.
11 *
12 * Libav is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15 * Lesser General Public License for more details.
16 *
17 * You should have received a copy of the GNU Lesser General Public
18 * License along with Libav; if not, write to the Free Software
19 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20 */
21
22 /**
23 * @file
24 * @brief H.264 packetization
25 * @author Luca Abeni <lucabe72@email.it>
26 */
27
28 #include "avformat.h"
29 #include "avc.h"
30 #include "rtpenc.h"
31
32 static const uint8_t *avc_mp4_find_startcode(const uint8_t *start, const uint8_t *end, int nal_length_size)
33 {
34 int res = 0;
35
36 if (end - start < nal_length_size)
37 return NULL;
38 while (nal_length_size--)
39 res = (res << 8) | *start++;
40
41 if (start + res > end || res < 0 || start + res < start)
42 return NULL;
43
44 return start + res;
45 }
46
47 static void nal_send(AVFormatContext *s1, const uint8_t *buf, int size, int last)
48 {
49 RTPMuxContext *s = s1->priv_data;
50
51 av_log(s1, AV_LOG_DEBUG, "Sending NAL %x of len %d M=%d\n", buf[0] & 0x1F, size, last);
52 if (size <= s->max_payload_size) {
53 ff_rtp_send_data(s1, buf, size, last);
54 } else {
55 uint8_t type = buf[0] & 0x1F;
56 uint8_t nri = buf[0] & 0x60;
57
58 av_log(s1, AV_LOG_DEBUG, "NAL size %d > %d\n", size, s->max_payload_size);
59 s->buf[0] = 28; /* FU Indicator; Type = 28 ---> FU-A */
60 s->buf[0] |= nri;
61 s->buf[1] = type;
62 s->buf[1] |= 1 << 7;
63 buf += 1;
64 size -= 1;
65 while (size + 2 > s->max_payload_size) {
66 memcpy(&s->buf[2], buf, s->max_payload_size - 2);
67 ff_rtp_send_data(s1, s->buf, s->max_payload_size, 0);
68 buf += s->max_payload_size - 2;
69 size -= s->max_payload_size - 2;
70 s->buf[1] &= ~(1 << 7);
71 }
72 s->buf[1] |= 1 << 6;
73 memcpy(&s->buf[2], buf, size);
74 ff_rtp_send_data(s1, s->buf, size + 2, last);
75 }
76 }
77
78 void ff_rtp_send_h264(AVFormatContext *s1, const uint8_t *buf1, int size)
79 {
80 const uint8_t *r, *end = buf1 + size;
81 RTPMuxContext *s = s1->priv_data;
82
83 s->timestamp = s->cur_timestamp;
84 if (s->nal_length_size)
85 r = avc_mp4_find_startcode(buf1, end, s->nal_length_size) ? buf1 : end;
86 else
87 r = ff_avc_find_startcode(buf1, end);
88 while (r < end) {
89 const uint8_t *r1;
90
91 if (s->nal_length_size) {
92 r1 = avc_mp4_find_startcode(r, end, s->nal_length_size);
93 if (!r1)
94 r1 = end;
95 r += s->nal_length_size;
96 } else {
97 while (!*(r++));
98 r1 = ff_avc_find_startcode(r, end);
99 }
100 nal_send(s1, r, r1 - r, r1 == end);
101 r = r1;
102 }
103 }