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 #define CAVS_SEQ_START_CODE 0x000001b0
27 #define CAVS_PIC_I_START_CODE 0x000001b3
28 #define CAVS_UNDEF_START_CODE 0x000001b4
29 #define CAVS_PIC_PB_START_CODE 0x000001b6
30 #define CAVS_VIDEO_EDIT_CODE 0x000001b7
31 #define CAVS_PROFILE_JIZHUN 0x20 // AVS1 P2
32 #define CAVS_PROFILE_GUANGDIAN 0x48 // AVS1 P16/AVS+
33
cavsvideo_probe(const AVProbeData *p)34 static int cavsvideo_probe(const AVProbeData *p)
35 {
36 uint32_t code= -1;
37 int pic=0, seq=0, slice_pos = 0;
38 const uint8_t *ptr = p->buf, *end = p->buf + p->buf_size;
39
40 while (ptr < end) {
41 ptr = avpriv_find_start_code(ptr, end, &code);
42 if ((code & 0xffffff00) == 0x100) {
43 if(code < CAVS_SEQ_START_CODE) {
44 /* slices have to be consecutive */
45 if(code < slice_pos)
46 return 0;
47 slice_pos = code;
48 } else {
49 slice_pos = 0;
50 }
51 if (code == CAVS_SEQ_START_CODE) {
52 seq++;
53 /* check for the only currently supported profile */
54 if (*ptr != CAVS_PROFILE_JIZHUN && *ptr != CAVS_PROFILE_GUANGDIAN)
55 return 0;
56 } else if ((code == CAVS_PIC_I_START_CODE) ||
57 (code == CAVS_PIC_PB_START_CODE)) {
58 pic++;
59 } else if ((code == CAVS_UNDEF_START_CODE) ||
60 (code > CAVS_VIDEO_EDIT_CODE)) {
61 return 0;
62 }
63 }
64 }
65 if(seq && seq*9<=pic*10)
66 return AVPROBE_SCORE_EXTENSION+1;
67 return 0;
68 }
69
70 FF_DEF_RAWVIDEO_DEMUXER(cavsvideo, "raw Chinese AVS (Audio Video Standard)", cavsvideo_probe, "avs", AV_CODEC_ID_CAVS)
71