speaking of gif animations

[Chipp Walters]

The problem is that Rev doesn't handle the temporal RLE compression in GIFs.
So, if you use such compression, you get the artifacting you were seeing.
Most browsers handle this type of optimization just fine, as the GIFs only
go in one direction: i.e. frame 1,frame 2, frame 3, etc. Temporal
optimization stores just the changes between frames. But in Rev, you may
need to play an animation backward or randomly, so that is the reason they
do not support temporal optimization.

BTW, this web service makes great spinning 'busy' gifs:
http://ajaxload.info/