So I was going through an old folder of MIDIs and found this file and I can't figure out what it is. It had a .mid extension, but the binary data looks like an mpeg-4 container. ExifTool says it's a quicktime movie, which tracks with the mpeg-4 theory, but mplayer can't open it and mp4box says it's an invalid IsoMedia file although YAMB says there's a 250x250 gif(?!) video stream. Motion jpeg is a thing, but gif is not made for actual video compression.
???????