A user interface unit in a graphics processing display pipe may include registers programmable with information that defines active regions of an image frame. Pixels within the active regions of the image frame are meant to be displayed, while pixels outside of the active regions of the image frame are not to be displayed. Fetch circuitry within the user interface unit may fetch frames from memory, fetching only the pixels within the active regions of the image frames as defined by the programmed contents of the registers. The user interface unit may then provide the fetched pixels to a blend unit to blend the fetched pixels with pixels from other frames or pixels of a video stream to produce output frames. When blended with pixels of a video stream, the fetched pixels may be displayed as a graphics overlay on top of the video stream.