blob: 33f84652ebe8cc6e043af5dd0163ca95fff0a089
| 1 | /* |
| 2 | * VC-1 demuxer |
| 3 | * Copyright (c) 2015 Carl Eugen Hoyos |
| 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 "avformat.h" |
| 23 | #include "rawdec.h" |
| 24 | #include "libavutil/intreadwrite.h" |
| 25 | #include "libavcodec/vc1_common.h" |
| 26 | |
| 27 | static int vc1_probe(AVProbeData *p) |
| 28 | { |
| 29 | int seq = 0, entry = 0, frame = 0, i; |
| 30 | |
| 31 | for (i = 0; i < p->buf_size + 5; i++) { |
| 32 | uint32_t code = AV_RB32(p->buf + i); |
| 33 | if ((code & 0xffffffe0) == 0x100) { |
| 34 | int type = code & 0x11f; |
| 35 | i += 4; |
| 36 | switch (type) { |
| 37 | case VC1_CODE_SEQHDR: { |
| 38 | int profile, level, chromaformat; |
| 39 | profile = (p->buf[i] & 0xc0) >> 6; |
| 40 | if (profile != PROFILE_ADVANCED) { |
| 41 | seq = 0; |
| 42 | continue; |
| 43 | } |
| 44 | level = (p->buf[i] & 0x38) >> 3; |
| 45 | if (level >= 5) { |
| 46 | seq = 0; |
| 47 | continue; |
| 48 | } |
| 49 | chromaformat = (p->buf[i] & 0x6) >> 1; |
| 50 | if (chromaformat != 1) { |
| 51 | seq = 0; |
| 52 | continue; |
| 53 | } |
| 54 | seq++; |
| 55 | i += 6; |
| 56 | break; |
| 57 | } |
| 58 | case VC1_CODE_ENTRYPOINT: |
| 59 | if (!seq) |
| 60 | continue; |
| 61 | entry++; |
| 62 | i += 2; |
| 63 | break; |
| 64 | case VC1_CODE_FRAME: |
| 65 | case VC1_CODE_FIELD: |
| 66 | case VC1_CODE_SLICE: |
| 67 | if (seq && entry) |
| 68 | frame++; |
| 69 | break; |
| 70 | } |
| 71 | } |
| 72 | } |
| 73 | |
| 74 | if (frame > 1) |
| 75 | return AVPROBE_SCORE_EXTENSION / 2 + 1; |
| 76 | if (frame == 1) |
| 77 | return AVPROBE_SCORE_EXTENSION / 4; |
| 78 | return 0; |
| 79 | } |
| 80 | |
| 81 | FF_DEF_RAWVIDEO_DEMUXER2(vc1, "raw VC-1", vc1_probe, "vc1", AV_CODEC_ID_VC1, AVFMT_GENERIC_INDEX|AVFMT_NOTIMESTAMPS) |
| 82 |