AVEncCommonBufferSize property

Specifies the size of the buffer used during encoding. This property applies only to constant bit rate (CBR) and variable bit rate (VBR) encoding modes.

This property is read/write.

Data type


Property GUID


Property value

This property has a linear range of values. To get the supported range, call ICodecAPI::GetParameterRange. Parameter ranges are not supported for H.264 UVC 1.5 camera encoders.


For some video formats the buffer size is specified in bits and for others it is specified in bytes. See the remarks below for specific information.

For MPEG video, this property defines the video buffer verifier (VBV) buffer size. The size of the buffer is in bits.

For H.264 video and Windows Media Video, the property defines the hypothetical reference decoder (HRD) size. The size of the buffer is in bytes.

For UVC 1.5 H264 encoding cameras, the CPB value sent to the camera encoder must be 16-bit aligned. The size of the buffer is in bytes.

This property is also used with H.264 UVC 1.5 camera encoders.


Requirement Value
Minimum supported client
Windows 2000 Professional [desktop apps | UWP apps]
Minimum supported server
Windows 2000 Server [desktop apps | UWP apps]

See also

Codec API Properties

ICodecAPI Interface