I just review the patches needed for kernel hwdec, and Armbian already has it, and build it as module.   here is the way you able to use hwdec.   1, download server image for orangepipc. hwdec not support X ot wayland. 2, build ffmpeg and mpv yourself.   A, build ffmpeg.   download ffmpeg 5.1.2 source from git or from ffmpeg.org (recommend git for easy apply patches) apply patches from https://github.com/jernejsk/FFmpeg     drmprime: v4l2-d