A processor receives input video data of a video dynamic range and input dynamic metadata. It also receives: input graphics data of a graphics dynamic range and input static metadata, display identification data from a target display over a video interface, and a blending priority map characterizing a per-pixel priority of output pixels in an image generated by blending the input video data and the input graphics data. A video mapping function and a graphics mapping function which map data from the input video and graphics dynamic ranges to the target dynamic range are generated based on the dynamic and static metadata. Then, the input and graphics data are blended based on the blending priority map and a per-pixel decision to map pixels to the target dynamic range using either the video mapping function or the graphics mapping function.