complete American Laser Games MM playback system, courtesy of Peter Ross

(suxen_drol at hotmail dot com)

Originally committed as revision 4999 to svn://svn.ffmpeg.org/ffmpeg/trunk

1 files changed, 216 insertions, 0 deletions

diff --git a/libavformat/mm.c b/libavformat/mm.c
new file mode 100644
index 0000000000..aa857d4c79
--- /dev/null
+++ b/libavformat/mm.c
@@ -0,0 +1,216 @@
+/*
+ * American Laser Games MM Format Demuxer
+ * Copyright (c) 2006 Peter Ross
+ *
+ * This library 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 of the License, or (at your option) any later version.
+ *
+ * This library 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 this library; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+
+/**
+ * @file mm.c
+ * American Laser Games MM Format Demuxer
+ * by Peter Ross (suxen_drol at hotmail dot com)
+ *
+ * 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 "avformat.h"
+
+#define MM_PREAMBLE_SIZE    6
+
+#define MM_TYPE_HEADER      0x0
+#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_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_PALETTE_COUNT    128
+#define MM_PALETTE_SIZE     (MM_PALETTE_COUNT*3)
+
+typedef struct {
+  AVPaletteControl palette_control;
+  unsigned int audio_pts, video_pts;
+} MmDemuxContext;
+
+static int mm_probe(AVProbeData *p)
+{
+    /* the first chunk is always the header */
+    if (p->buf_size < MM_PREAMBLE_SIZE)
+        return 0;
+    if (LE_16(&p->buf[0]) != MM_TYPE_HEADER)
+        return 0;
+    if (LE_32(&p->buf[2]) != MM_HEADER_LEN_V && LE_32(&p->buf[2]) != MM_HEADER_LEN_AV)
+        return 0;
+
+    /* only return half certainty since this check is a bit sketchy */
+    return AVPROBE_SCORE_MAX / 2;
+}
+
+static int mm_read_header(AVFormatContext *s,
+                           AVFormatParameters *ap)
+{
+    MmDemuxContext *mm = (MmDemuxContext *)s->priv_data;
+    ByteIOContext *pb = &s->pb;
+    AVStream *st;
+
+    unsigned int type, length;
+    unsigned int frame_rate, width, height;
+
+    type = get_le16(pb);
+    length = get_le32(pb);
+
+    if (type != MM_TYPE_HEADER)
+        return AVERROR_INVALIDDATA;
+
+    /* read header */
+    get_le16(pb);   /* total number of chunks */
+    frame_rate = get_le16(pb);
+    get_le16(pb);   /* ibm-pc video bios mode */
+    width = get_le16(pb);
+    height = get_le16(pb);
+    url_fseek(pb, length - 10, SEEK_CUR);  /* unknown data */
+
+    /* video stream */
+    st = av_new_stream(s, 0);
+    if (!st)
+        return AVERROR_NOMEM;
+    st->codec->codec_type = CODEC_TYPE_VIDEO;
+    st->codec->codec_id = CODEC_ID_MMVIDEO;
+    st->codec->codec_tag = 0;  /* no fourcc */
+    st->codec->width = width;
+    st->codec->height = height;
+    st->codec->palctrl = &mm->palette_control;
+    av_set_pts_info(st, 64, 1, frame_rate);
+
+    /* audio stream */
+    if (length == MM_HEADER_LEN_AV) {
+        st = av_new_stream(s, 0);
+        if (!st)
+            return AVERROR_NOMEM;
+        st->codec->codec_type = CODEC_TYPE_AUDIO;
+        st->codec->codec_tag = 0; /* no fourcc */
+        st->codec->codec_id = CODEC_ID_PCM_U8;
+        st->codec->channels = 1;
+        st->codec->sample_rate = 8000;
+        av_set_pts_info(st, 64, 1, 8000); /* 8000 hz */
+    }
+
+    mm->palette_control.palette_changed = 0;
+    mm->audio_pts = 0;
+    mm->video_pts = 0;
+    return 0;
+}
+
+static int mm_read_packet(AVFormatContext *s,
+                           AVPacket *pkt)
+{
+    MmDemuxContext *mm = (MmDemuxContext *)s->priv_data;
+    ByteIOContext *pb = &s->pb;
+    unsigned char preamble[MM_PREAMBLE_SIZE];
+    unsigned char pal[MM_PALETTE_SIZE];
+    unsigned int type, length;
+    int i;
+
+    while(1) {
+
+        if (get_buffer(pb, preamble, MM_PREAMBLE_SIZE) != MM_PREAMBLE_SIZE) {
+            return AVERROR_IO;
+        }
+
+        type = LE_16(&preamble[0]);
+        length = LE_16(&preamble[2]);
+
+        switch(type) {
+        case MM_TYPE_PALETTE :
+            url_fseek(pb, 4, SEEK_CUR);  /* unknown data */
+            if (get_buffer(pb, pal, MM_PALETTE_SIZE) != MM_PALETTE_SIZE)
+                return AVERROR_IO;
+            url_fseek(pb, length - (4 + MM_PALETTE_SIZE), SEEK_CUR);
+
+            for (i=0; i<MM_PALETTE_COUNT; i++) {
+                int r = pal[i*3 + 0];
+                int g = pal[i*3 + 1];
+                int b = pal[i*3 + 2];
+                mm->palette_control.palette[i] = (r << 16) | (g << 8) | (b);
+                /* repeat palette, where each components is multiplied by four */
+                mm->palette_control.palette[i+128] = (r << 18) | (g << 10) | (b<<2);
+            }
+            mm->palette_control.palette_changed = 1;
+            break;
+
+        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 (av_new_packet(pkt, length + MM_PREAMBLE_SIZE))
+                return AVERROR_NOMEM;
+            memcpy(pkt->data, preamble, MM_PREAMBLE_SIZE);
+            if (get_buffer(pb, pkt->data + MM_PREAMBLE_SIZE, length) != length)
+                return AVERROR_IO;
+            pkt->size = length + MM_PREAMBLE_SIZE;
+            pkt->stream_index = 0;
+            pkt->pts = mm->video_pts++;
+            return 0;
+
+        case MM_TYPE_AUDIO :
+            if (av_get_packet(&s->pb, pkt, length)<0)
+                return AVERROR_NOMEM;
+            pkt->size = length;
+            pkt->stream_index = 1;
+            pkt->pts = mm->audio_pts++;
+            return 0;
+
+        default :
+            av_log(NULL, AV_LOG_INFO, "mm: unknown chunk type 0x%x\n", type);
+            url_fseek(pb, length, SEEK_CUR);
+        }
+    }
+
+    return 0;
+}
+
+static int mm_read_close(AVFormatContext *s)
+{
+    return 0;
+}
+
+static AVInputFormat mm_iformat = {
+    "mm",
+    "American Laser Games MM format",
+    sizeof(MmDemuxContext),
+    mm_probe,
+    mm_read_header,
+    mm_read_packet,
+    mm_read_close,
+};
+
+int mm_init(void)
+{
+    av_register_input_format(&mm_iformat);
+    return 0;
+}