CODECAPI_AVEncVideoLTRBufferControl property

Specifies the maximum number of Long Term Reference (LTR) frames controlled by application.

Data type


Property GUID


Property value

The value of this control includes two fields, where each field has 16 bits.

Value Meaning
The first field
The number of LTR frames controlled by the application.
H.264/AVC encoders:
Assuming the value is N and N is non-zero value, at each IDR frame the encoder must automatically mark the frames following the IDR frame (and including the IDR frame) as LTR frames as long as all 3 of the following apply:
  • The frame is not already set to be marked as a long term reference frame.
  • The frame is a base layer frame. For example, syntax element temporal_id equal to 0.
  • The number of frames currently marked as LTR is less than N.

The second field
The trust mode of LTR control.
H.264/AVC encoders:
1 (Trust Until) means the encoder may use an LTR frame unless the app explicitly invalidates it through the CODECAPI_AVEncVideoUseLTRFrame control.
Other values are invalid and reserved for future use.


This is a static API.

Default value shall be 0


Minimum supported client
Windows 8.1 [desktop apps | UWP apps]
Minimum supported server
Windows Server 2012 R2 [desktop apps | UWP apps]

See also

Media Foundation Properties