WTV is a format for videos recorded by Windows Media Center where video is encoded by MPEG-2, MPEG-4 or h.264 and audio – by MPEG-1 Layer II or Dolby Digital AC-3. WTV file can contain video, audio, text and other data. The container replaced DVR-MS that was used by previous versions of the Windows program. WTV supports DRM that allows protection of the content by its owner.

WebM is an open media container compressed with VP8 video codec and Vorbis audio codec. WebM format has high video playback quality and data compression parameters.The format is widely used for adding media to web pages and it is supported by all modern web-browsers like Opera, Mozilla Firefox and Google Chrome. The embedding of WebM videos to a site page realizes without delays and errors. WebM is meant to be an alternative to the h.264 standard. The copyright of the extension is held by Google.