SPRUI30H November 2015 – May 2024 DRA745 , DRA746 , DRA750 , DRA756
The overlay optimization consists in fetching only the required pixels (that is, pixels that contribute to the final picture to be displayed [LCD1, LCD2, LCD3, or TV]). The decision to fetch the pixel from memory is based on the information available in the registers and on the following rules:
The result of the overlay optimization is a reduction of the bandwidth by fetching only the mandatory pixels. The overlay mechanism is independent for each overlay: LCD1, LCD2, LCD3, and TV. Because each layer (GFX, VID1, VID2, and VID3) can be associated to only one overlay at a time, it is possible to optimize the fetch of the pixels for each layer based on the overlay information. The overlay optimization must be run on the DMA engine time window and not on the display time window. The pixels are fetched by the DMA engine before the display processing.
The overlay optimization is enabled by setting the following bits to 0x1: