Windows 7 uses its own codecs for decoding several audio and video formats. Using third party DirectShow filters instead of the native filters is not possible without making difficult changes to the Windows Registry.
The Win7DSFilterTweaker tool allows you to configure your preferred DirectShow decoders with just a few mouse clicks. It is quick, easy, and changes can always be undone.
If you for example prefer to use ffdshow or CoreAVC for decoding H.264 video then you can do so by using this tool.
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