blob: b46c33f7e2febe4e2b87f0e295bd458d7c4e02d4
| 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 | */ |
| 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 | |
| 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 |