Can't help ya there, but I will say that avi files are best manipulated as uncompressed, then compress the finished avi. This will give the best kwality. I know these can be very big, but I have a 20G drive. ;) And Microsoft usually won't give up much info without getting money, ie. getting the SDK. Have you tried using MPEG compression? Final quality is still very good, and it is much more accessable to the un-monied public.