Statistics
| Branch: | Revision:

ffmpeg / libavformat / cavsvideodec.c @ 2912e87a

History | View | Annotate | Download (2.48 KB)

1
/*
2
 * RAW Chinese AVS video demuxer
3
 * Copyright (c) 2009  Stefan Gehrer <stefan.gehrer@gmx.de>
4
 *
5
 * This file is part of Libav.
6
 *
7
 * Libav 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
 * Libav 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 Libav; 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 CAVS_SEQ_START_CODE       0x000001b0
26
#define CAVS_PIC_I_START_CODE     0x000001b3
27
#define CAVS_UNDEF_START_CODE     0x000001b4
28
#define CAVS_PIC_PB_START_CODE    0x000001b6
29
#define CAVS_VIDEO_EDIT_CODE      0x000001b7
30
#define CAVS_PROFILE_JIZHUN       0x20
31

    
32
static int cavsvideo_probe(AVProbeData *p)
33
{
34
    uint32_t code= -1;
35
    int pic=0, seq=0, slice_pos = 0;
36
    int i;
37

    
38
    for(i=0; i<p->buf_size; i++){
39
        code = (code<<8) + p->buf[i];
40
        if ((code & 0xffffff00) == 0x100) {
41
            if(code < CAVS_SEQ_START_CODE) {
42
                /* slices have to be consecutive */
43
                if(code < slice_pos)
44
                    return 0;
45
                slice_pos = code;
46
            } else {
47
                slice_pos = 0;
48
            }
49
            if (code == CAVS_SEQ_START_CODE) {
50
                seq++;
51
                /* check for the only currently supported profile */
52
                if(p->buf[i+1] != CAVS_PROFILE_JIZHUN)
53
                    return 0;
54
            } else if ((code == CAVS_PIC_I_START_CODE) ||
55
                       (code == CAVS_PIC_PB_START_CODE)) {
56
                pic++;
57
            } else if ((code == CAVS_UNDEF_START_CODE) ||
58
                       (code >  CAVS_VIDEO_EDIT_CODE)) {
59
                return 0;
60
            }
61
        }
62
    }
63
    if(seq && seq*9<=pic*10)
64
        return AVPROBE_SCORE_MAX/2;
65
    return 0;
66
}
67

    
68
AVInputFormat ff_cavsvideo_demuxer = {
69
    "cavsvideo",
70
    NULL_IF_CONFIG_SMALL("raw Chinese AVS video"),
71
    0,
72
    cavsvideo_probe,
73
    ff_raw_video_read_header,
74
    ff_raw_read_partial_packet,
75
    .flags= AVFMT_GENERIC_INDEX,
76
    .value = CODEC_ID_CAVS,
77
};