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 "startcode.h"
30
31/** Markers used in VC-1 AP frame data */
32//@{
33enum 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//@{
48enum 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 */
59static 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
70static 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