1 /*
2 * VC-1 and WMV3 decoder
3 * Copyright (c) 2006-2007 Konstantin Shishkov
4 * Partly based on vc9.c (c) 2005 Anonymous, Alex Beregszaszi, Michael Niedermayer
5 *
6 * This file is part of FFmpeg.
7 *
8 * FFmpeg is free software; you can redistribute it and/or
9 * modify it under the terms of the GNU Lesser General Public
10 * License as published by the Free Software Foundation; either
11 * version 2.1 of the License, or (at your option) any later version.
12 *
13 * FFmpeg is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16 * Lesser General Public License for more details.
17 *
18 * You should have received a copy of the GNU Lesser General Public
19 * License along with FFmpeg; if not, write to the Free Software
20 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
21 */
22
23 #ifndef AVCODEC_VC1_COMMON_H
24 #define AVCODEC_VC1_COMMON_H
25
26 #include <stdint.h>
27
28 #include "libavutil/attributes.h"
29 #include "internal.h"
30
31 /** Markers used in VC-1 AP frame data */
32 //@{
33 enum VC1Code {
34 VC1_CODE_RES0 = 0x00000100,
35 VC1_CODE_ENDOFSEQ = 0x0000010A,
36 VC1_CODE_SLICE,
37 VC1_CODE_FIELD,
38 VC1_CODE_FRAME,
39 VC1_CODE_ENTRYPOINT,
40 VC1_CODE_SEQHDR,
41 };
42 //@}
43
44 #define IS_MARKER(x) (((x) & ~0xFF) == VC1_CODE_RES0)
45
46 /** Available Profiles */
47 //@{
48 enum Profile {
49 PROFILE_SIMPLE,
50 PROFILE_MAIN,
51 PROFILE_COMPLEX, ///< TODO: WMV9 specific
52 PROFILE_ADVANCED
53 };
54 //@}
55
56 /** Find VC-1 marker in buffer
57 * @return position where next marker starts or end of buffer if no marker found
58 */
find_next_marker(const uint8_t * src,const uint8_t * end)59 static av_always_inline const uint8_t* find_next_marker(const uint8_t *src, const uint8_t *end)
60 {
61 if (end - src >= 4) {
62 uint32_t mrk = 0xFFFFFFFF;
63 src = avpriv_find_start_code(src, end, &mrk);
64 if (IS_MARKER(mrk))
65 return src - 4;
66 }
67 return end;
68 }
69
vc1_unescape_buffer(const uint8_t * src,int size,uint8_t * dst)70 static av_always_inline int vc1_unescape_buffer(const uint8_t *src, int size, uint8_t *dst)
71 {
72 int dsize = 0, i;
73
74 if (size < 4) {
75 for (dsize = 0; dsize < size; dsize++)
76 *dst++ = *src++;
77 return size;
78 }
79 for (i = 0; i < size; i++, src++) {
80 if (src[0] == 3 && i >= 2 && !src[-1] && !src[-2] && i < size-1 && src[1] < 4) {
81 dst[dsize++] = src[1];
82 src++;
83 i++;
84 } else
85 dst[dsize++] = *src;
86 }
87 return dsize;
88 }
89
90 #endif /* AVCODEC_VC1_COMMON_H */
91