Because of my job, I have to convert any and every type of video and audio file you can imagine. I can guarantee you, that if you download the latest version of Any Video Converter, (5.5 I think is the most current) and it's free, it will convert your .264 files to .avi, or other formats very easily. Open the program, then you can either drag your .264 files into the window to convert, or add manually by browsing. Select the type of output you want, ie. .avi, .mp4 etc, (there are LOTS!!) then click Convert Now. It's that simple. I've tried most of the others, and I have AVS as well but you have to PAY for that one! This free one is the best one I've found for most surveillance file types.