Specifies the device role for an audio capture device.

Data type

ERole stored as UINT32


To get this attribute, call IMFAttributes::GetUINT32.

To set this attribute, call IMFAttributes::SetUINT32.


The eRole enumeration type is documented in the Core Audio API documentation.

The value of the attribute specifies a device role. This attribute is used with the following functions.

This attribute can be used as input to the MFCreateDeviceSource and MFCreateDeviceSourceActivate functions. If the attribute is specified, the function creates a media source that uses the default audio capture device for the specified device role.

This attribute can also be used as input to the MFEnumDeviceSources function. If the attribute is specified, the enumeration is restricted to the specified device role. In addition, each activation object returned by the MFEnumDeviceSources function contains this attribute. The attribute is then used internally by the activation object when it creates the media source.

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


Requirement Value
Minimum supported client
Windows 7 [desktop apps only]
Minimum supported server
Windows Server 2008 R2 [desktop apps only]

See also

Alphabetical List of Media Foundation Attributes

Audio/Video Capture

Capture Device Attributes