Fix two checks in the AAC packetiser, which were too conservative
[libav.git] / libavformat / rtp_aac.c
CommitLineData
171dce48
LA
1/*
2 * copyright (c) 2007 Luca Abeni
3 *
4 * This file is part of FFmpeg.
5 *
6 * FFmpeg is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU Lesser General Public
8 * License as published by the Free Software Foundation; either
9 * version 2.1 of the License, or (at your option) any later version.
10 *
11 * FFmpeg is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 * Lesser General Public License for more details.
15 *
16 * You should have received a copy of the GNU Lesser General Public
17 * License along with FFmpeg; if not, write to the Free Software
18 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
19 */
20
21#include "avformat.h"
302879cb 22#include "rtpenc.h"
171dce48 23
e0d21bfe 24#define MAX_FRAMES_PER_PACKET (s->max_frames_per_packet ? s->max_frames_per_packet : 5)
171dce48
LA
25#define MAX_AU_HEADERS_SIZE (2 + 2 * MAX_FRAMES_PER_PACKET)
26
27void ff_rtp_send_aac(AVFormatContext *s1, const uint8_t *buff, int size)
28{
302879cb 29 RTPMuxContext *s = s1->priv_data;
171dce48
LA
30 int len, max_packet_size;
31 uint8_t *p;
32
33 /* skip ADTS header, if present */
34 if ((s1->streams[0]->codec->extradata_size) == 0) {
35 size -= 7;
36 buff += 7;
37 }
38 max_packet_size = s->max_payload_size - MAX_AU_HEADERS_SIZE;
39
40 /* test if the packet must be sent */
41 len = (s->buf_ptr - s->buf);
d2ce53b7 42 if ((s->num_frames == MAX_FRAMES_PER_PACKET) || (len && (len + size) > s->max_payload_size)) {
21da81d7 43 int au_size = s->num_frames * 2;
171dce48
LA
44
45 p = s->buf + MAX_AU_HEADERS_SIZE - au_size - 2;
46 if (p != s->buf) {
47 memmove(p + 2, s->buf + 2, au_size);
48 }
49 /* Write the AU header size */
50 p[0] = ((au_size * 8) & 0xFF) >> 8;
51 p[1] = (au_size * 8) & 0xFF;
52
53 ff_rtp_send_data(s1, p, s->buf_ptr - p, 1);
54
21da81d7 55 s->num_frames = 0;
171dce48 56 }
21da81d7 57 if (s->num_frames == 0) {
171dce48
LA
58 s->buf_ptr = s->buf + MAX_AU_HEADERS_SIZE;
59 s->timestamp = s->cur_timestamp;
60 }
61
d2ce53b7 62 if (size <= max_packet_size) {
21da81d7 63 p = s->buf + s->num_frames++ * 2 + 2;
171dce48
LA
64 *p++ = size >> 5;
65 *p = (size & 0x1F) << 3;
66 memcpy(s->buf_ptr, buff, size);
67 s->buf_ptr += size;
68 } else {
1a3a0a79
LA
69 if (s->buf_ptr != s->buf + MAX_AU_HEADERS_SIZE) {
70 av_log(s1, AV_LOG_ERROR, "Strange...\n");
71 av_abort();
72 }
73 max_packet_size = s->max_payload_size - 4;
74 p = s->buf;
75 p[0] = 0;
76 p[1] = 16;
77 while (size > 0) {
78 len = FFMIN(size, max_packet_size);
79 p[2] = len >> 5;
80 p[3] = (size & 0x1F) << 3;
81 memcpy(p + 4, buff, len);
82 ff_rtp_send_data(s1, p, len + 4, len == size);
83 size -= len;
84 buff += len;
85 }
171dce48
LA
86 }
87}