In our last article, we began to examine the most popular file formats for digital video. Now, let’s take a look at four more and briefly discuss their attributes.

.WMV files. WMV stands for Windows Media Video, and refers to a video codec set developed by Microsoft. In earlier versions, Microsoft utilized a form of MPEG-4 technology in developing this codec, but later versions has relied more on Microsoft’s own technology. It is a widely used file format on the internet because of its relatively small file size, and is now used in other media players beyond Windows Media Player (referring to version 9).

.ASF files. ASF is short for Advanced Streaming Format. It is a very compressed format that contains streaming audio, video, slide shows, and synchronized events. It provides a continuous stream of data, so that even lengthy videos begin playing almost immediately. It is not necessary for the entire file to download first. This is a popular internet file format, especially for online seminars or other lengthy subjects.

.RM files (also .RA or .RAM). A .RM file is a Real Media file, which (of course) is played in Real Media Player. These files are generally intended to be used as streaming files, and cannot be played in other media players.

.MP4 files (or .M4V). MP4, or MPEG-4 is a format developed by the Motion Picture Experts Group that allows you to combine multiple media streams into one file. Initially, the MPEG-4 format looked a lot like the Apple Quicktime format, but has since been significantly changed and improved upon. It is an end-user format that is used most often for streaming applications and mobile devices (PDA’s, cell phones, etc.). The great appeal of this format is its general quality level in relation to its small file size.

Hopefully, these two articles will serve as a basic reference for you on video file formats, and help you to more quickly identify file types in the future.