libavformat/mm.c

   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 "avio_internal.h"
  38 #include "demux.h"
  39 #include "internal.h"
  40
  41 #define MM_PREAMBLE_SIZE    6
  42
  43 #define MM_TYPE_HEADER      0x0
  44 #define MM_TYPE_RAW         0x2
  45 #define MM_TYPE_INTER       0x5
  46 #define MM_TYPE_INTRA       0x8
  47 #define MM_TYPE_INTRA_HH    0xc
  48 #define MM_TYPE_INTER_HH    0xd
  49 #define MM_TYPE_INTRA_HHV   0xe
  50 #define MM_TYPE_INTER_HHV   0xf
  51 #define MM_TYPE_AUDIO2      0x14
  52 #define MM_TYPE_AUDIO       0x15
  53 #define MM_TYPE_PALETTE     0x31
  54
  55 #define MM_HEADER_LEN_V     0x16    /* video only */
  56 #define MM_HEADER_LEN_AV    0x18    /* video + audio */
  57 #define MM_HEADER_LEN_AV2   0x1a
  58
  59 #define MM_PALETTE_COUNT    128
  60 #define MM_PALETTE_SIZE     (MM_PALETTE_COUNT*3)
  61
  62 static int probe(const AVProbeData *p)
  63 {
  64     int len, type, fps, w, h;
  65     if (p->buf_size < MM_HEADER_LEN_AV + MM_PREAMBLE_SIZE)
  66         return 0;
  67     /* the first chunk is always the header */
  68     if (AV_RL16(&p->buf[0]) != MM_TYPE_HEADER)
  69         return 0;
  70     len = AV_RL32(&p->buf[2]);
  71     if (len != MM_HEADER_LEN_V && len != MM_HEADER_LEN_AV && len != MM_HEADER_LEN_AV2)
  72         return 0;
  73     fps = AV_RL16(&p->buf[8]);
  74     w = AV_RL16(&p->buf[12]);
  75     h = AV_RL16(&p->buf[14]);
  76     if (!fps || fps > 60 || !w || w > 2048 || !h || h > 2048)
  77         return 0;
  78     type = AV_RL16(&p->buf[len]);
  79     if (!type || type > 0x31)
  80         return 0;
  81
  82     /* only return half certainty since this check is a bit sketchy */
  83     return AVPROBE_SCORE_EXTENSION;
  84 }
  85
  86 static int read_header(AVFormatContext *s)
  87 {
  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 || length < 10)
  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->codecpar->codec_type = AVMEDIA_TYPE_VIDEO;
 113     st->codecpar->codec_id = AV_CODEC_ID_MMVIDEO;
 114     st->codecpar->codec_tag = 0;  /* no fourcc */
 115     st->codecpar->width = width;
 116     st->codecpar->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->codecpar->codec_type = AVMEDIA_TYPE_AUDIO;
 125         st->codecpar->codec_tag = 0; /* no fourcc */
 126         st->codecpar->codec_id = AV_CODEC_ID_PCM_U8;
 127         st->codecpar->ch_layout = (AVChannelLayout)AV_CHANNEL_LAYOUT_MONO;
 128         st->codecpar->sample_rate = 8000;
 129         avpriv_set_pts_info(st, 64, 1, 8000); /* 8000 hz */
 130     }
 131
 132     return 0;
 133 }
 134
 135 static int read_packet(AVFormatContext *s,
 136                            AVPacket *pkt)
 137 {
 138     AVIOContext *pb = s->pb;
 139     unsigned char preamble[MM_PREAMBLE_SIZE];
 140     unsigned int type, length;
 141     int64_t pos = avio_tell(pb);
 142     int ret;
 143
 144     while (1) {
 145         if (avio_feof(pb))
 146             return AVERROR_EOF;
 147
 148         ret = ffio_read_size(pb, preamble, MM_PREAMBLE_SIZE);
 149         if (ret < 0)
 150             return ret;
 151
 152         type = AV_RL16(&preamble[0]);
 153         length = AV_RL16(&preamble[2]);
 154
 155         switch (type) {
 156         case MM_TYPE_RAW :
 157         case MM_TYPE_PALETTE :
 158         case MM_TYPE_INTER :
 159         case MM_TYPE_INTRA :
 160         case MM_TYPE_INTRA_HH :
 161         case MM_TYPE_INTER_HH :
 162         case MM_TYPE_INTRA_HHV :
 163         case MM_TYPE_INTER_HHV :
 164             /* output preamble + data */
 165             if ((ret = av_new_packet(pkt, length + MM_PREAMBLE_SIZE)) < 0)
 166                 return ret;
 167             memcpy(pkt->data, preamble, MM_PREAMBLE_SIZE);
 168             ret = ffio_read_size(pb, pkt->data + MM_PREAMBLE_SIZE, length);
 169             if (ret < 0)
 170                 return ret;
 171             pkt->size = length + MM_PREAMBLE_SIZE;
 172             pkt->stream_index = 0;
 173             if (type!=MM_TYPE_PALETTE)
 174                 pkt->duration = 1;
 175             if (type == MM_TYPE_RAW ||
 176                 type == MM_TYPE_INTRA)
 177                 pkt->flags |= AV_PKT_FLAG_KEY;
 178             pkt->pos = pos;
 179             return 0;
 180
 181         case MM_TYPE_AUDIO :
 182             if (s->nb_streams < 2)
 183                 return AVERROR_INVALIDDATA;
 184             if ((ret = av_get_packet(s->pb, pkt, length)) < 0)
 185                 return ret;
 186             pkt->stream_index = 1;
 187             pkt->duration = length;
 188             pkt->pos = pos;
 189             return 0;
 190
 191         default :
 192             av_log(s, AV_LOG_INFO, "unknown chunk type 0x%x\n", type);
 193             /* fallthrough */
 194         case MM_TYPE_AUDIO2 :
 195             avio_skip(pb, length);
 196         }
 197     }
 198 }
 199
 200 const FFInputFormat ff_mm_demuxer = {
 201     .p.name         = "mm",
 202     .p.long_name    = NULL_IF_CONFIG_SMALL("American Laser Games MM"),
 203     .p.flags        = AVFMT_GENERIC_INDEX,
 204     .read_probe     = probe,
 205     .read_header    = read_header,
 206     .read_packet    = read_packet,
 207 };