| 1 | /* |
| 2 | * Metar Gear Solid: The Twin Snakes demuxer |
| 3 | * Copyright (c) 2012 Paul B Mahol |
| 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 "libavutil/intreadwrite.h" |
| 23 | #include "libavutil/intfloat.h" |
| 24 | #include "avformat.h" |
| 25 | #include "riff.h" |
| 26 | |
| 27 | static int read_probe(AVProbeData *p) |
| 28 | { |
| 29 | if (AV_RB32(p->buf ) != 0x000E || |
| 30 | AV_RB32(p->buf + 4) != 0x0050 || |
| 31 | AV_RB32(p->buf + 12) != 0x0034) |
| 32 | return 0; |
| 33 | return AVPROBE_SCORE_MAX; |
| 34 | } |
| 35 | |
| 36 | static int read_header(AVFormatContext *s) |
| 37 | { |
| 38 | AVIOContext *pb = s->pb; |
| 39 | AVStream *st; |
| 40 | AVRational fps; |
| 41 | uint32_t chunk_size; |
| 42 | |
| 43 | avio_skip(pb, 4); |
| 44 | chunk_size = avio_rb32(pb); |
| 45 | if (chunk_size != 80) |
| 46 | return AVERROR(EIO); |
| 47 | avio_skip(pb, 20); |
| 48 | |
| 49 | st = avformat_new_stream(s, 0); |
| 50 | if (!st) |
| 51 | return AVERROR(ENOMEM); |
| 52 | |
| 53 | st->need_parsing = AVSTREAM_PARSE_HEADERS; |
| 54 | st->start_time = 0; |
| 55 | st->nb_frames = |
| 56 | st->duration = avio_rb32(pb); |
| 57 | fps = av_d2q(av_int2float(avio_rb32(pb)), INT_MAX); |
| 58 | st->codec->width = avio_rb32(pb); |
| 59 | st->codec->height = avio_rb32(pb); |
| 60 | avio_skip(pb, 12); |
| 61 | st->codec->codec_type = AVMEDIA_TYPE_VIDEO; |
| 62 | st->codec->codec_tag = avio_rb32(pb); |
| 63 | st->codec->codec_id = ff_codec_get_id(ff_codec_bmp_tags, |
| 64 | st->codec->codec_tag); |
| 65 | avpriv_set_pts_info(st, 64, fps.den, fps.num); |
| 66 | avio_skip(pb, 20); |
| 67 | |
| 68 | return 0; |
| 69 | } |
| 70 | |
| 71 | static int read_packet(AVFormatContext *s, AVPacket *pkt) |
| 72 | { |
| 73 | AVIOContext *pb = s->pb; |
| 74 | uint32_t chunk_size, payload_size; |
| 75 | int ret; |
| 76 | |
| 77 | if (avio_feof(pb)) |
| 78 | return AVERROR_EOF; |
| 79 | |
| 80 | avio_skip(pb, 4); |
| 81 | chunk_size = avio_rb32(pb); |
| 82 | avio_skip(pb, 4); |
| 83 | payload_size = avio_rb32(pb); |
| 84 | |
| 85 | if (chunk_size < payload_size + 16) |
| 86 | return AVERROR(EIO); |
| 87 | |
| 88 | ret = av_get_packet(pb, pkt, payload_size); |
| 89 | if (ret < 0) |
| 90 | return ret; |
| 91 | |
| 92 | pkt->pos -= 16; |
| 93 | pkt->duration = 1; |
| 94 | avio_skip(pb, chunk_size - (ret + 16)); |
| 95 | |
| 96 | return ret; |
| 97 | } |
| 98 | |
| 99 | AVInputFormat ff_mgsts_demuxer = { |
| 100 | .name = "mgsts", |
| 101 | .long_name = NULL_IF_CONFIG_SMALL("Metal Gear Solid: The Twin Snakes"), |
| 102 | .read_probe = read_probe, |
| 103 | .read_header = read_header, |
| 104 | .read_packet = read_packet, |
| 105 | .flags = AVFMT_GENERIC_INDEX, |
| 106 | }; |