VMD playing error patch by (Kostya (cannonball bw-team com>)

"I recently got a game called Lighthouse from Sierra with FMV in VMD
format. Some of them played OK, some of them FFmpeg refused to open,
some caused a crash.

I investigated files which couldn't be opened by FFmpeg and it appeared
that they had no audio (and bytes 2-3 from beginning of file contained
01 00, all other have 00 00 insted). Attached patch fixes this issue."

Originally committed as revision 3934 to svn://svn.ffmpeg.org/ffmpeg/trunk

libavformat/sierravmd.c

@@ -185,6 +185,7 @@ static int vmd_read_header(AVFormatContext *s,
 
     /* each on-disk VMD frame has an audio part and a video part; demuxer
      * accounts them separately */
+    if(vmd->sample_rate)
 	vmd->frame_count *= 2;
     raw_frame_table = NULL;
     vmd->frame_table = NULL;