blob: 34d434f7d26e5cdd9f7407ca3949724bf685897d
1 | /* |
2 | * RAW MPEG-4 video demuxer |
3 | * Copyright (c) 2006 Thijs Vermeir <thijs.vermeir@barco.com> |
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 | #define VISUAL_OBJECT_START_CODE 0x000001b5 |
26 | #define VOP_START_CODE 0x000001b6 |
27 | |
28 | static int mpeg4video_probe(AVProbeData *probe_packet) |
29 | { |
30 | uint32_t temp_buffer = -1; |
31 | int VO = 0, VOL = 0, VOP = 0, VISO = 0, res = 0; |
32 | int i; |
33 | |
34 | for (i = 0; i < probe_packet->buf_size; i++) { |
35 | temp_buffer = (temp_buffer << 8) + probe_packet->buf[i]; |
36 | if (temp_buffer & 0xfffffe00) |
37 | continue; |
38 | if (temp_buffer < 2) |
39 | continue; |
40 | |
41 | if (temp_buffer == VOP_START_CODE) |
42 | VOP++; |
43 | else if (temp_buffer == VISUAL_OBJECT_START_CODE) |
44 | VISO++; |
45 | else if (temp_buffer >= 0x100 && temp_buffer < 0x120) |
46 | VO++; |
47 | else if (temp_buffer >= 0x120 && temp_buffer < 0x130) |
48 | VOL++; |
49 | else if (!(0x1AF < temp_buffer && temp_buffer < 0x1B7) && |
50 | !(0x1B9 < temp_buffer && temp_buffer < 0x1C4)) |
51 | res++; |
52 | } |
53 | |
54 | if (VOP >= VISO && VOP >= VOL && VO >= VOL && VOL > 0 && res == 0) |
55 | return VOP+VO > 4 ? AVPROBE_SCORE_EXTENSION : AVPROBE_SCORE_EXTENSION/2; |
56 | |
57 | if (VOP >= VISO && VOP >= VOL && VO >= VOL && VOL > 0 && VOP+VO > 4) |
58 | return AVPROBE_SCORE_EXTENSION/10; |
59 | return 0; |
60 | } |
61 | |
62 | FF_DEF_RAWVIDEO_DEMUXER2(m4v, "raw MPEG-4 video", mpeg4video_probe, "m4v", |
63 | AV_CODEC_ID_MPEG4, AVFMT_GENERIC_INDEX | AVFMT_TS_DISCONT) |
64 |