Windows Media Video, or WMV, is Microsoft’s family of video codecs including WMV 7, WMV 8, and WMV 9. It can handle anything from low resolution video for dial-up Internet users to HDTV. The latest generation of WMV, based on the WMV 9 codec, has been standardized and approved as a new and more open codec known as VC-1. While all versions of WMV support variable bit rate, average bit rate, and constant bit rate, WMV 9 introduced several important features including native support for interlaced video, non-square pixels, and frame interpolation.
Audio Video Interleave, known as AVI, is a multimedia container format created by Microsoft in 1992. AVI files contain both audio and video data and support synchronous audio-with-video playback. An AVI container can support virtually any compression scheme including Full Frame (uncompressed), Intel Real Time (Indeo), Cinepak, Motion JPEG, Real Video, MPEG-4 and others.