/src/ffmpeg/libavformat/cavsvideodec.c
Line | Count | Source |
1 | | /* |
2 | | * RAW Chinese AVS video demuxer |
3 | | * Copyright (c) 2009 Stefan Gehrer <stefan.gehrer@gmx.de> |
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 "libavcodec/startcode.h" |
23 | | #include "avformat.h" |
24 | | #include "rawdec.h" |
25 | | |
26 | 3.93M | #define CAVS_SEQ_START_CODE 0x000001b0 |
27 | 1.80M | #define CAVS_PIC_I_START_CODE 0x000001b3 |
28 | 1.65M | #define CAVS_UNDEF_START_CODE 0x000001b4 |
29 | 1.74M | #define CAVS_PIC_PB_START_CODE 0x000001b6 |
30 | 1.65M | #define CAVS_VIDEO_EDIT_CODE 0x000001b7 |
31 | 100k | #define CAVS_PROFILE_JIZHUN 0x20 // AVS1 P2 |
32 | 41.3k | #define CAVS_PROFILE_GUANGDIAN 0x48 // AVS1 P16/AVS+ |
33 | | |
34 | | static int cavsvideo_probe(const AVProbeData *p) |
35 | 963k | { |
36 | 963k | uint32_t code= -1; |
37 | 963k | int pic=0, seq=0, slice_pos = 0; |
38 | 963k | const uint8_t *ptr = p->buf, *end = p->buf + p->buf_size; |
39 | | |
40 | 3.13M | while (ptr < end) { |
41 | 2.59M | ptr = avpriv_find_start_code(ptr, end, &code); |
42 | 2.59M | if ((code & 0xffffff00) == 0x100) { |
43 | 2.07M | if(code < CAVS_SEQ_START_CODE) { |
44 | | /* slices have to be consecutive */ |
45 | 1.66M | if(code < slice_pos) |
46 | 214k | return 0; |
47 | 1.45M | slice_pos = code; |
48 | 1.45M | } else { |
49 | 407k | slice_pos = 0; |
50 | 407k | } |
51 | 1.85M | if (code == CAVS_SEQ_START_CODE) { |
52 | 50.0k | seq++; |
53 | | /* check for the only currently supported profile */ |
54 | 50.0k | if (*ptr != CAVS_PROFILE_JIZHUN && *ptr != CAVS_PROFILE_GUANGDIAN) |
55 | 38.4k | return 0; |
56 | 1.80M | } else if ((code == CAVS_PIC_I_START_CODE) || |
57 | 1.74M | (code == CAVS_PIC_PB_START_CODE)) { |
58 | 155k | pic++; |
59 | 1.65M | } else if ((code == CAVS_UNDEF_START_CODE) || |
60 | 1.65M | (code > CAVS_VIDEO_EDIT_CODE)) { |
61 | 173k | return 0; |
62 | 173k | } |
63 | 1.85M | } |
64 | 2.59M | } |
65 | 536k | if(seq && seq*9<=pic*10) |
66 | 517 | return AVPROBE_SCORE_EXTENSION+1; |
67 | 536k | return 0; |
68 | 536k | } |
69 | | |
70 | | FF_DEF_RAWVIDEO_DEMUXER(cavsvideo, "raw Chinese AVS (Audio Video Standard)", cavsvideo_probe, "avs", AV_CODEC_ID_CAVS) |