WMV (Windows Media Video) is a generic name for video encoding solutions that Microsoft developed. The format is a part of the Windows Media framework that also includes formats like Windows Media Audio (WMA), Advanced Systems Format (ASF), and High Definition Photo (HDP). WMV files use the Microsoft container format and represent Microsoft’s own version of MPEG-4 (Part 2) video encoding technology.

First introduced in 1999, the WMV format now competes with other codecs such as DivX and RealVideo as a means of distributing video content on the World Wide Web. Microsoft introduced subsequent versions of the codec in the years 2001 and 2003.

The built-in player in Windows, Windows Media Player (version 7 upwards), and most third party video players such as the VLC Media Player, BSPlayer, MPlayer, and WinAMP play WMV files.

The .wmv extension usually describes files in ASF format that use Windows Media Video codecs. Audio codecs are usually versions of Windows Media Audio or the Sipro ACELP.net audio codec. The extension is sometimes shortened to .wm.

Although it is usually packed into the ASF container format, the WMV file can also be converted to AVI with the WMV9 video compression manager codec implementation.

Main features

Windows Media Video’s main features are:

  • Data delivery over a wide variety of network protocols
  • Suitable for local playback
  • Advanced multimedia capabilities:
    • Extensible media types
    • Component download
    • Scalable media types
    • Stream prioritization as the author defines
    • Support for multiple languages
    • Document and content management