Windows Media

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See also Windows Media Player

Windows Media is a generic name for the set of proprietary streaming audio and video technologies developed by Microsoft. It includes the Windows Media Video (WMV) and Windows Media Audio (WMA) codecs.

Windows Media Video is not built solely on Microsoft in-house technology. From version 7 (WMV1), Microsoft has used its own non-standard version of MPEG-4 Part 2.

Windows Media is often generated using Microsoft's proprietary Windows Media Video 9 VCM software for Windows.

Microsoft has submitted Version 9 codec to the Society of Motion Picture and Television Engineers (SMPTE), for approval as an international standard. The Trial version of standards were published by SMPTE in September 2005. A reference decoder implementation and test sequences are also available. This codec is used to distribute high definition video on standard DVDs in a format Microsoft has branded as WMV HD, which can be played back on computers or compatible DVD players.

Encoding

You can encode audio to WMA format with following command

% vlc input.wav :sout="#transcode{acodec=wma2,ab=128,channels=2,samplerate=44100}:std{access=file,mux=asf,dst=output.wma}"

You can encode video and audio to WMV format with following command

% vlc input.avi :sout="#transcode{vcodec=WMV2,width=720,vb=1200,height=576,acodec=wma2,ab=128,channels=2}:std{access=file,mux=asf,dst=output.wmv}"

Container

Windows Media files use the ASF container. They generally have the file extension .wmv, .wma, .wm or .asf.

Windows Media codecs can also be used inside AVI files.

Codecs used in WMV files

See next paragraph for more information on codecs in WMV files.

Codecs

WMV3
This is a video codec. The name to use at the command line is WMV3, but you can also use WMV.
This codec can be used inside the Windows Media containers.
WMV2
This is a video codec. The name to use at the command line is WMV2, but you can also use WMV.
This codec can be used inside the Windows Media containers.
WMA2
This is an audio codec. The name to use at the command line is WMA2, but you can also use WMA.
This codec can be used inside the Windows Media containers.

Windows Media often uses special native codecs for Windows Media Video and Windows Media Audio. WMV3 is often called "Windows Media 9".

Fourcc Codec Supported by VLC? Comments
MP43 MPEG-4 Up-to-date
WMV1 Windows Media Video v7 Up-to-date
WMV2 Windows Media Video v8 Up-to-date Not totally implemented for rare files. Please send the files.
WMV3 Windows Media Video 9 (v3) Up-to-date Not totally implemented for rare files (VBR). Please send the files.
WVC1, WMVA Windows Media Video 9 Advanced Profile Up-to-date Not totally implemented for rare files (VBR, interlacing). Please send the files.
WMVP Windows Media Video 9 Image Up-to-date VLC 2.0 or through dmo for older versions
WVP2 Windows Media Video 9.1 Image (v2) Up-to-date VLC 2.0 or through dmo for older versions
MSS1 Windows Media Screen v7 Up-to-date with dmo ONLY
MSS2 Windows Media Video 9 screen codec Up-to-date with dmo ONLY

More info on MSDN

Compatibility

Protected content

Windows Media files may contain Digital Restrictions Management (DRM) facilities intended to protect copyrights. VLC does not play any DRM'd files.

Windows Media Video 3

WMV3, the Video part of Windows Media 9, is supported in VLC since version 0.8.6. Upgrade to the latest version (3.0.10) to play WMV files.

If you are unable to upgrade, there are still some fixes. If you're using Windows and have Windows Media Player 9/10 installed, VLC should be able to play these files, by using Microsoft's own files. Or, if you're using Linux, see the Common Problems page for a workaround.

On Windows Media Player (Mac)

Microsoft's Windows Media Player for the Mac does not support all WMV encoded files since it supports only the ASF file container.[Please check this]