Today, Microsoft’s interoperability team released a new Firefox add-on that enables Firefox users on Windows to play H.264-encoded video on HTML5 by using the built-in capabilities found in Windows 7.
The HTML5 Extension for Windows Media Player Firefox Plug-in extends the functionality of the earlier plug-in for Firefox, and enables web pages that offer video in the H.264 format using standard W3C HTML5 to work in Firefox on Windows. Because H.264 video on the web is so prevalent, this interoperability bridge is important for Firefox users of Windows.
H.264 is a very well established and widely supported video compression format, developed for use in high definition systems such as HDTV, Blu-ray and HD DVD as well as low resolution portable devices. It also offers better quality at lower file sizes than both MPEG-2 and MPEG-4 ASP (DivX or XviD).
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