/* * American Laser Games MM Format Demuxer * Copyright (c) 2006 Peter Ross * * This file is part of FFmpeg. * * FFmpeg is free software; you can redistribute it and/or * modify it under the terms of the GNU Lesser General Public * License as published by the Free Software Foundation; either * version 2.1 of the License, or (at your option) any later version. * * FFmpeg is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * Lesser General Public License for more details. * * You should have received a copy of the GNU Lesser General Public * License along with FFmpeg; if not, write to the Free Software * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA */ /** * @file * American Laser Games MM Format Demuxer * by Peter Ross (pross@xvid.org) * * The MM format was used by IBM-PC ports of ALG's "arcade shooter" games, * including Mad Dog McCree and Crime Patrol. * * Technical details here: * http://wiki.multimedia.cx/index.php?title=American_Laser_Games_MM */ #include "libavutil/channel_layout.h" #include "libavutil/intreadwrite.h" #include "avformat.h" #include "demux.h" #include "internal.h" #define MM_PREAMBLE_SIZE 6 #define MM_TYPE_HEADER 0x0 #define MM_TYPE_RAW 0x2 #define MM_TYPE_INTER 0x5 #define MM_TYPE_INTRA 0x8 #define MM_TYPE_INTRA_HH 0xc #define MM_TYPE_INTER_HH 0xd #define MM_TYPE_INTRA_HHV 0xe #define MM_TYPE_INTER_HHV 0xf #define MM_TYPE_AUDIO2 0x14 #define MM_TYPE_AUDIO 0x15 #define MM_TYPE_PALETTE 0x31 #define MM_HEADER_LEN_V 0x16 /* video only */ #define MM_HEADER_LEN_AV 0x18 /* video + audio */ #define MM_HEADER_LEN_AV2 0x1a #define MM_PALETTE_COUNT 128 #define MM_PALETTE_SIZE (MM_PALETTE_COUNT*3) static int probe(const AVProbeData *p) { int len, type, fps, w, h; if (p->buf_size < MM_HEADER_LEN_AV + MM_PREAMBLE_SIZE) return 0; /* the first chunk is always the header */ if (AV_RL16(&p->buf[0]) != MM_TYPE_HEADER) return 0; len = AV_RL32(&p->buf[2]); if (len != MM_HEADER_LEN_V && len != MM_HEADER_LEN_AV && len != MM_HEADER_LEN_AV2) return 0; fps = AV_RL16(&p->buf[8]); w = AV_RL16(&p->buf[12]); h = AV_RL16(&p->buf[14]); if (!fps || fps > 60 || !w || w > 2048 || !h || h > 2048) return 0; type = AV_RL16(&p->buf[len]); if (!type || type > 0x31) return 0; /* only return half certainty since this check is a bit sketchy */ return AVPROBE_SCORE_EXTENSION; } static int read_header(AVFormatContext *s) { AVIOContext *pb = s->pb; AVStream *st; unsigned int type, length; unsigned int frame_rate, width, height; type = avio_rl16(pb); length = avio_rl32(pb); if (type != MM_TYPE_HEADER || length < 10) return AVERROR_INVALIDDATA; /* read header */ avio_rl16(pb); /* total number of chunks */ frame_rate = avio_rl16(pb); avio_rl16(pb); /* ibm-pc video bios mode */ width = avio_rl16(pb); height = avio_rl16(pb); avio_skip(pb, length - 10); /* unknown data */ /* video stream */ st = avformat_new_stream(s, NULL); if (!st) return AVERROR(ENOMEM); st->codecpar->codec_type = AVMEDIA_TYPE_VIDEO; st->codecpar->codec_id = AV_CODEC_ID_MMVIDEO; st->codecpar->codec_tag = 0; /* no fourcc */ st->codecpar->width = width; st->codecpar->height = height; avpriv_set_pts_info(st, 64, 1, frame_rate); /* audio stream */ if (length >= MM_HEADER_LEN_AV) { st = avformat_new_stream(s, NULL); if (!st) return AVERROR(ENOMEM); st->codecpar->codec_type = AVMEDIA_TYPE_AUDIO; st->codecpar->codec_tag = 0; /* no fourcc */ st->codecpar->codec_id = AV_CODEC_ID_PCM_U8; st->codecpar->ch_layout = (AVChannelLayout)AV_CHANNEL_LAYOUT_MONO; st->codecpar->sample_rate = 8000; avpriv_set_pts_info(st, 64, 1, 8000); /* 8000 hz */ } return 0; } static int read_packet(AVFormatContext *s, AVPacket *pkt) { AVIOContext *pb = s->pb; unsigned char preamble[MM_PREAMBLE_SIZE]; unsigned int type, length; int64_t pos = avio_tell(pb); int ret; while (1) { if (avio_feof(pb)) return AVERROR_EOF; if (avio_read(pb, preamble, MM_PREAMBLE_SIZE) != MM_PREAMBLE_SIZE) return AVERROR(EIO); type = AV_RL16(&preamble[0]); length = AV_RL16(&preamble[2]); switch (type) { case MM_TYPE_RAW : case MM_TYPE_PALETTE : case MM_TYPE_INTER : case MM_TYPE_INTRA : case MM_TYPE_INTRA_HH : case MM_TYPE_INTER_HH : case MM_TYPE_INTRA_HHV : case MM_TYPE_INTER_HHV : /* output preamble + data */ if ((ret = av_new_packet(pkt, length + MM_PREAMBLE_SIZE)) < 0) return ret; memcpy(pkt->data, preamble, MM_PREAMBLE_SIZE); if (avio_read(pb, pkt->data + MM_PREAMBLE_SIZE, length) != length) return AVERROR(EIO); pkt->size = length + MM_PREAMBLE_SIZE; pkt->stream_index = 0; if (type!=MM_TYPE_PALETTE) pkt->duration = 1; if (type == MM_TYPE_RAW || type == MM_TYPE_INTRA) pkt->flags |= AV_PKT_FLAG_KEY; pkt->pos = pos; return 0; case MM_TYPE_AUDIO : if (s->nb_streams < 2) return AVERROR_INVALIDDATA; if ((ret = av_get_packet(s->pb, pkt, length)) < 0) return ret; pkt->stream_index = 1; pkt->duration = length; pkt->pos = pos; return 0; default : av_log(s, AV_LOG_INFO, "unknown chunk type 0x%x\n", type); /* fallthrough */ case MM_TYPE_AUDIO2 : avio_skip(pb, length); } } } const FFInputFormat ff_mm_demuxer = { .p.name = "mm", .p.long_name = NULL_IF_CONFIG_SMALL("American Laser Games MM"), .p.flags = AVFMT_GENERIC_INDEX, .read_probe = probe, .read_header = read_header, .read_packet = read_packet, };