Windows Media Video
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Windows Media Video (WMV) is a generic name for the set of proprietary streaming video technologies developed by Microsoft. It is part of the Windows Media framework.
WMV is not built solely on Microsoft in-house technology. From version 7 (WMV1), Microsoft has used its own non-standard version of MPEG-4. The video stream is often combined with an audio stream of Windows Media Audio.
WMV files are customarily played by Windows Media Player on Microsoft Windows and Macintosh systems. Some third-party players also exist, such as MPlayer for Linux, which play back WMV by using the FFmpeg implementation of the WMV codecs.
Raw WMV video is packed into an AVI or Advanced Streaming Format (ASF) container. The resulting files may be named .avi if it is an AVI-contained file, or .wmv or .asf if it is an ASF file, but .wmv files are to be ASF files with audio/video content only.
WMV is usually found in the AVI file container when encoded with Microsoft's Windows Media Video 9 VCM software for Windows. Microsoft's Windows Media Player for the Mac does not support all WMV encoded files since it supports only the ASF file container.
WMV also features digital rights management facilities.
Microsoft has submitted Version 9 codec to the Society of Motion Picture and Television Engineers (SMPTE), for approval as an international standard. (As of Jan 2005, the SMPTE is reviewing the submission under the draft-name "VC-1"). This codec is also used to distribute high definition video on standard DVDs in a format Microsoft has branded as WMV HD. This WMV HD content can be played back on computers or compatible DVD players.
See also
- FFmpeg - a third-party WMV decoder library
- MPlayer - third-party open source cross-platform media player capable of playing many WMV files
- Windows Media Audio - the sound-only counterpart
External links
- Windows Media Homepage at Microsoft (http://www.microsoft.com/windowsmedia/)
- Description of the algorithm used for Windows Media encryption (http://www.spinnaker.com/crypt/drm/freeme/Technical)
- Windows Media High Definition Video (http://www.wmvhd.com)de:Microsoft Windows Media Video