What is it exactly that you are trying to do? I would assume that CRAM is not the compression method, as Microsoft Video 1 is a video codec in itself, but perhaps it is the compression ratio. I found some white papers on Video capture, and the .AVI file format, there may be some useful information here: http://www.microsoft.com/hwdev/vidcap/#fPapers Also, here is another site that goes in depth into Video Compression codecs: http://www.codeccentral.com/Codecs/ Hope this helps you out. co(V)(V)union