MFT_TRANSFORM_CLSID_Attribute attribute

Contains the class identifier (CLSID) of a Media Foundation transform (MFT).

Data type



To get this attribute, call IMFAttributes::GetGUID.

To set this attribute, call IMFAttributes::SetGUID.


This attribute is set on the IMFActivate pointers returned by the MFTEnumEx function.

This attribute is used internally by the activation object when it creates the MFT. Applications should not use this CLSID directly to create the MFT, because the activation object might need to initialize the MFT. Therefore, to create an instance of the MFT, call IMFActivate::ActivateObject on the activation object.

Note that the MFTEnumEx function behaves differently than the MFTEnum function in this respect. The MFTEnum function returns CLSIDs, which the application passes to the CoCreateInstance function. The MFTEnumEx function returns activation objects rather than CLSIDs.

The GUID constant for this attribute is exported from mfuuid.lib.


Minimum supported client

Windows 7 [desktop apps | Windows Store apps]

Minimum supported server

Windows Server 2008 R2 [desktop apps | Windows Store apps]



See also

Alphabetical List of Media Foundation Attributes
Transform Attributes