I don't know what compression it uses as I am new to capturing video and have to do it on my time off. I use the program that is built into the card for capturing video from my camcorder. I just have to hook up the camcorder (easy as the instructions have good drawings), start the camcorder and press a button within the on-screen-display to begin the capture. The program puts the captured video in a folder called "WinFast WorkArea" for me to use at my convenience. The controls are easy to use once you get it set up. There is a large button on the right side of the software control screen (similar to juke box program controls in size) which changes the source for TV to CBVS (source: camcorder) and S-Video (also source: camera if your camera has that input). I had problems with sound until I set the source to line in and everything work fine after that change. I capture stuff in MPEG 2 optimum quality right now and it does a good job with great video depending on source. I do know that 20 minutes of video in this quality takes up 634 MB of hard disk space, so an hour of video would take up a little over a 2 GB of space. I am using XP Pro and that is why I chose this card as all the reviews said that it worked well with XP. I tried the Hauppage with bad results and a friend of mine tried the FLY98 card with bad sound results. All I can tell you is about my success. There isn't much information about capturing in the instruction but I didn't have much trouble figuring it out on my own. If you need any more information just ask that's what we're here for.