1 /*
2 * Copyright (C) 2008 Ramiro Polla
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
24
25 #define HEADER_SIZE 24
26
27 /*
28 * Header structure:
29 * uint16_t ss; // struct size
30 * uint16_t width; // frame width
31 * uint16_t height; // frame height
32 * uint16_t ff; // keyframe + some other info(???)
33 * uint32_t size; // size of data
34 * uint32_t fourcc; // ML20
35 * uint32_t u3; // ?
36 * uint32_t ts; // time
37 */
38
40 {
41 int i;
42
45 uint32_t fourcc;
47
48 if(bytestream_get_le16(&bytestream) != HEADER_SIZE)
49 continue;
50 width = bytestream_get_le16(&bytestream);
51 height = bytestream_get_le16(&bytestream);
52 if(!(width==320 && height==240) && !(width==160 && height==120))
53 continue;
54 bytestream += 2; // keyframe
55 bytestream += 4; // size
56 fourcc = bytestream_get_le32(&bytestream);
57 if(fourcc !=
MKTAG(
'M',
'L',
'2',
'0'))
58 continue;
59
60 if(i) {
61 if(i < 14) /* starts with SwitchBoard connection info */
63 else /* starts in the middle of stream */
65 } else {
67 }
68 }
69
70 return -1;
71 }
72
74 {
78
80 if(!st)
82
87
89
90 /* Some files start with "connected\r\n\r\n".
91 * So skip until we find the first byte of struct size */
93
96 return -1;
97 }
98
99 return 0;
100 }
101
103 {
105 uint16_t keyframe;
106 uint32_t
size, timestamp;
107
108 avio_skip(pb, 1);
/* one byte has been read ahead */
116
118 return -1;
119
120 avio_skip(pb, 1);
/* Read ahead one byte of struct size like read_header */
121
122 pkt->
pts = timestamp;
123 pkt->
dts = timestamp;
125
126 /* Some aMsn generated videos (or was it Mercury Messenger?) don't set
127 * this bit and rely on the codec to get keyframe information */
128 if(keyframe&1)
130
132 }
133
140 };