Microsoft Locks Mpeg4 H264 Codecs In Windows 7
Windows 7 will support various popular multimedia codecs like Mpeg4, H.264 or AAC out of the box which reduces the codec finding troubles that some users experience when trying to play certain multimedia files in the Windows operating system. A Directshow developer for the ffdshow tryouts application took a closer look at how Windows 7 uses those codecs and discovered that Microsoft seems to have locked the use of alternative decoders in Windows Media Center and Windows Media Player for both the Mpeg4 and H264 format.
Even worse than this is that there is no way to override those locked codecs since those preferred codecs are owned by the TrustedInstaller user in the Windows Registry which means it is not possible to edit the settings even as a Windows 7 admin. The test has been conduced on build 7057 of Windows 7. The researcher thinks that it is unlikely that Microsoft will change the behavior in the soon to be released Windows 7 Release Candidate.
One reason for the protection of those codecs in Windows Media Center and Windows Media Player could be compatibility reasons. Third party multimedia players on the other hand are not affected or limited in any way by this.
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