*/
/**
- * @file mm.c
+ * @file libavformat/mm.c
* American Laser Games MM Format Demuxer
- * by Peter Ross (suxen_drol at hotmail dot com)
+ * 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.
* http://wiki.multimedia.cx/index.php?title=American_Laser_Games_MM
*/
+#include "libavutil/intreadwrite.h"
#include "avformat.h"
#define MM_PREAMBLE_SIZE 6
#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)
+static int probe(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;
- if (AV_RL32(&p->buf[2]) != MM_HEADER_LEN_V && AV_RL32(&p->buf[2]) != MM_HEADER_LEN_AV)
+ len = AV_RL32(&p->buf[2]);
+ if (len != MM_HEADER_LEN_V && len != MM_HEADER_LEN_AV)
+ 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_MAX / 2;
}
-static int mm_read_header(AVFormatContext *s,
+static int read_header(AVFormatContext *s,
AVFormatParameters *ap)
{
MmDemuxContext *mm = s->priv_data;
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 */
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,
+static int read_packet(AVFormatContext *s,
AVPacket *pkt)
{
MmDemuxContext *mm = 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) {
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(EIO);
- 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 :
return AVERROR(EIO);
pkt->size = length + MM_PREAMBLE_SIZE;
pkt->stream_index = 0;
- pkt->pts = mm->video_pts++;
+ pkt->pts = mm->video_pts;
+ if (type!=MM_TYPE_PALETTE)
+ mm->video_pts++;
return 0;
case MM_TYPE_AUDIO :
return 0;
default :
- av_log(NULL, AV_LOG_INFO, "mm: unknown chunk type 0x%x\n", type);
+ av_log(s, AV_LOG_INFO, "unknown chunk type 0x%x\n", type);
url_fseek(pb, length, SEEK_CUR);
}
}
return 0;
}
-static int mm_read_close(AVFormatContext *s)
-{
- return 0;
-}
-
AVInputFormat mm_demuxer = {
"mm",
NULL_IF_CONFIG_SMALL("American Laser Games MM format"),
sizeof(MmDemuxContext),
- mm_probe,
- mm_read_header,
- mm_read_packet,
- mm_read_close,
+ probe,
+ read_header,
+ read_packet,
};