Commit | Line | Data |
---|---|---|
2ba45a60 DM |
1 | /* |
2 | * RAW H.263 video demuxer | |
3 | * Copyright (c) 2009 Michael Niedermayer <michaelni@gmx.at> | |
4 | * | |
5 | * This file is part of FFmpeg. | |
6 | * | |
7 | * FFmpeg 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 | * FFmpeg 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 FFmpeg; if not, write to the Free Software | |
19 | * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA | |
20 | */ | |
21 | ||
22 | #include "avformat.h" | |
23 | #include "rawdec.h" | |
24 | ||
25 | static int h263_probe(AVProbeData *p) | |
26 | { | |
27 | uint64_t code= -1; | |
28 | int i; | |
29 | int valid_psc=0; | |
30 | int invalid_psc=0; | |
31 | int res_change=0; | |
32 | int src_fmt, last_src_fmt=-1; | |
33 | int last_gn=0; | |
34 | int tr, last_tr = -1; | |
35 | ||
36 | for(i=0; i<p->buf_size; i++){ | |
37 | code = (code<<8) + p->buf[i]; | |
38 | if ((code & 0xfffffc000000) == 0x80000000) { | |
39 | tr = (code >> 18) & 0xFF; | |
40 | src_fmt= (code>>10)&7; | |
41 | if( src_fmt != last_src_fmt | |
42 | && last_src_fmt>0 && last_src_fmt<6 | |
43 | && src_fmt<6) | |
44 | res_change++; | |
45 | ||
46 | if (tr == last_tr) { | |
47 | invalid_psc++; | |
48 | continue; | |
49 | } | |
50 | ||
51 | if (src_fmt != 7 && !(code&(1<<9)) && (code&(1<<5))) { | |
52 | invalid_psc++; | |
53 | continue; | |
54 | } | |
55 | ||
56 | if((code&0x30000)==0x20000 && src_fmt){ | |
57 | valid_psc++; | |
58 | last_gn=0; | |
59 | }else | |
60 | invalid_psc++; | |
61 | last_src_fmt= src_fmt; | |
62 | last_tr = tr; | |
63 | } else if((code & 0xffff80000000) == 0x80000000) { | |
64 | int gn= (code>>(31-5)) & 0x1F; | |
65 | if(gn<last_gn){ | |
66 | invalid_psc++; | |
67 | }else | |
68 | last_gn= gn; | |
69 | } | |
70 | } | |
71 | if(valid_psc > 2*invalid_psc + 2*res_change + 3){ | |
72 | return AVPROBE_SCORE_EXTENSION; | |
73 | }else if(valid_psc > 2*invalid_psc) | |
74 | return AVPROBE_SCORE_EXTENSION / 2; | |
75 | return 0; | |
76 | } | |
77 | ||
78 | FF_DEF_RAWVIDEO_DEMUXER(h263, "raw H.263", h263_probe, NULL, AV_CODEC_ID_H263) |