| 1 | /* |
| 2 | * American Laser Games MM Format Demuxer |
| 3 | * Copyright (c) 2006 Peter Ross |
| 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 | /** |
| 23 | * @file |
| 24 | * American Laser Games MM Format Demuxer |
| 25 | * by Peter Ross (pross@xvid.org) |
| 26 | * |
| 27 | * The MM format was used by IBM-PC ports of ALG's "arcade shooter" games, |
| 28 | * including Mad Dog McCree and Crime Patrol. |
| 29 | * |
| 30 | * Technical details here: |
| 31 | * http://wiki.multimedia.cx/index.php?title=American_Laser_Games_MM |
| 32 | */ |
| 33 | |
| 34 | #include "libavutil/channel_layout.h" |
| 35 | #include "libavutil/intreadwrite.h" |
| 36 | #include "avformat.h" |
| 37 | #include "internal.h" |
| 38 | |
| 39 | #define MM_PREAMBLE_SIZE 6 |
| 40 | |
| 41 | #define MM_TYPE_HEADER 0x0 |
| 42 | #define MM_TYPE_INTER 0x5 |
| 43 | #define MM_TYPE_INTRA 0x8 |
| 44 | #define MM_TYPE_INTRA_HH 0xc |
| 45 | #define MM_TYPE_INTER_HH 0xd |
| 46 | #define MM_TYPE_INTRA_HHV 0xe |
| 47 | #define MM_TYPE_INTER_HHV 0xf |
| 48 | #define MM_TYPE_AUDIO 0x15 |
| 49 | #define MM_TYPE_PALETTE 0x31 |
| 50 | |
| 51 | #define MM_HEADER_LEN_V 0x16 /* video only */ |
| 52 | #define MM_HEADER_LEN_AV 0x18 /* video + audio */ |
| 53 | |
| 54 | #define MM_PALETTE_COUNT 128 |
| 55 | #define MM_PALETTE_SIZE (MM_PALETTE_COUNT*3) |
| 56 | |
| 57 | typedef struct { |
| 58 | unsigned int audio_pts, video_pts; |
| 59 | } MmDemuxContext; |
| 60 | |
| 61 | static int probe(AVProbeData *p) |
| 62 | { |
| 63 | int len, type, fps, w, h; |
| 64 | if (p->buf_size < MM_HEADER_LEN_AV + MM_PREAMBLE_SIZE) |
| 65 | return 0; |
| 66 | /* the first chunk is always the header */ |
| 67 | if (AV_RL16(&p->buf[0]) != MM_TYPE_HEADER) |
| 68 | return 0; |
| 69 | len = AV_RL32(&p->buf[2]); |
| 70 | if (len != MM_HEADER_LEN_V && len != MM_HEADER_LEN_AV) |
| 71 | return 0; |
| 72 | fps = AV_RL16(&p->buf[8]); |
| 73 | w = AV_RL16(&p->buf[12]); |
| 74 | h = AV_RL16(&p->buf[14]); |
| 75 | if (!fps || fps > 60 || !w || w > 2048 || !h || h > 2048) |
| 76 | return 0; |
| 77 | type = AV_RL16(&p->buf[len]); |
| 78 | if (!type || type > 0x31) |
| 79 | return 0; |
| 80 | |
| 81 | /* only return half certainty since this check is a bit sketchy */ |
| 82 | return AVPROBE_SCORE_EXTENSION; |
| 83 | } |
| 84 | |
| 85 | static int read_header(AVFormatContext *s) |
| 86 | { |
| 87 | MmDemuxContext *mm = s->priv_data; |
| 88 | AVIOContext *pb = s->pb; |
| 89 | AVStream *st; |
| 90 | |
| 91 | unsigned int type, length; |
| 92 | unsigned int frame_rate, width, height; |
| 93 | |
| 94 | type = avio_rl16(pb); |
| 95 | length = avio_rl32(pb); |
| 96 | |
| 97 | if (type != MM_TYPE_HEADER) |
| 98 | return AVERROR_INVALIDDATA; |
| 99 | |
| 100 | /* read header */ |
| 101 | avio_rl16(pb); /* total number of chunks */ |
| 102 | frame_rate = avio_rl16(pb); |
| 103 | avio_rl16(pb); /* ibm-pc video bios mode */ |
| 104 | width = avio_rl16(pb); |
| 105 | height = avio_rl16(pb); |
| 106 | avio_skip(pb, length - 10); /* unknown data */ |
| 107 | |
| 108 | /* video stream */ |
| 109 | st = avformat_new_stream(s, NULL); |
| 110 | if (!st) |
| 111 | return AVERROR(ENOMEM); |
| 112 | st->codec->codec_type = AVMEDIA_TYPE_VIDEO; |
| 113 | st->codec->codec_id = AV_CODEC_ID_MMVIDEO; |
| 114 | st->codec->codec_tag = 0; /* no fourcc */ |
| 115 | st->codec->width = width; |
| 116 | st->codec->height = height; |
| 117 | avpriv_set_pts_info(st, 64, 1, frame_rate); |
| 118 | |
| 119 | /* audio stream */ |
| 120 | if (length == MM_HEADER_LEN_AV) { |
| 121 | st = avformat_new_stream(s, NULL); |
| 122 | if (!st) |
| 123 | return AVERROR(ENOMEM); |
| 124 | st->codec->codec_type = AVMEDIA_TYPE_AUDIO; |
| 125 | st->codec->codec_tag = 0; /* no fourcc */ |
| 126 | st->codec->codec_id = AV_CODEC_ID_PCM_U8; |
| 127 | st->codec->channels = 1; |
| 128 | st->codec->channel_layout = AV_CH_LAYOUT_MONO; |
| 129 | st->codec->sample_rate = 8000; |
| 130 | avpriv_set_pts_info(st, 64, 1, 8000); /* 8000 hz */ |
| 131 | } |
| 132 | |
| 133 | mm->audio_pts = 0; |
| 134 | mm->video_pts = 0; |
| 135 | return 0; |
| 136 | } |
| 137 | |
| 138 | static int read_packet(AVFormatContext *s, |
| 139 | AVPacket *pkt) |
| 140 | { |
| 141 | MmDemuxContext *mm = s->priv_data; |
| 142 | AVIOContext *pb = s->pb; |
| 143 | unsigned char preamble[MM_PREAMBLE_SIZE]; |
| 144 | unsigned int type, length; |
| 145 | |
| 146 | while(1) { |
| 147 | |
| 148 | if (avio_read(pb, preamble, MM_PREAMBLE_SIZE) != MM_PREAMBLE_SIZE) { |
| 149 | return AVERROR(EIO); |
| 150 | } |
| 151 | |
| 152 | type = AV_RL16(&preamble[0]); |
| 153 | length = AV_RL16(&preamble[2]); |
| 154 | |
| 155 | switch(type) { |
| 156 | case MM_TYPE_PALETTE : |
| 157 | case MM_TYPE_INTER : |
| 158 | case MM_TYPE_INTRA : |
| 159 | case MM_TYPE_INTRA_HH : |
| 160 | case MM_TYPE_INTER_HH : |
| 161 | case MM_TYPE_INTRA_HHV : |
| 162 | case MM_TYPE_INTER_HHV : |
| 163 | /* output preamble + data */ |
| 164 | if (av_new_packet(pkt, length + MM_PREAMBLE_SIZE)) |
| 165 | return AVERROR(ENOMEM); |
| 166 | memcpy(pkt->data, preamble, MM_PREAMBLE_SIZE); |
| 167 | if (avio_read(pb, pkt->data + MM_PREAMBLE_SIZE, length) != length) |
| 168 | return AVERROR(EIO); |
| 169 | pkt->size = length + MM_PREAMBLE_SIZE; |
| 170 | pkt->stream_index = 0; |
| 171 | pkt->pts = mm->video_pts; |
| 172 | if (type!=MM_TYPE_PALETTE) |
| 173 | mm->video_pts++; |
| 174 | return 0; |
| 175 | |
| 176 | case MM_TYPE_AUDIO : |
| 177 | if (av_get_packet(s->pb, pkt, length)<0) |
| 178 | return AVERROR(ENOMEM); |
| 179 | pkt->stream_index = 1; |
| 180 | pkt->pts = mm->audio_pts++; |
| 181 | return 0; |
| 182 | |
| 183 | default : |
| 184 | av_log(s, AV_LOG_INFO, "unknown chunk type 0x%x\n", type); |
| 185 | avio_skip(pb, length); |
| 186 | } |
| 187 | } |
| 188 | } |
| 189 | |
| 190 | AVInputFormat ff_mm_demuxer = { |
| 191 | .name = "mm", |
| 192 | .long_name = NULL_IF_CONFIG_SMALL("American Laser Games MM"), |
| 193 | .priv_data_size = sizeof(MmDemuxContext), |
| 194 | .read_probe = probe, |
| 195 | .read_header = read_header, |
| 196 | .read_packet = read_packet, |
| 197 | }; |