I want to point out (again) that the colour distortions and green lines in the images in post #1 are due to the current Amlogic hardware video-decode driver. It is not in a good state. It generally works okay with older Amlogic hardware and less okay with newer. The driver is in staging and is effectively unmaintained for 2+ years, and it predates SM1/S905X3 hardware being released. There is also a dependency on the codec and version of firmware blobs being used (lots of variables).
You should be aware that current LE (needed for some level of HC4 support) is running completely different kernel codebase and drivers to older harware running older LE images or CE which are using vendor kernels. The upstream kernel and vendor kernel drivers have zero in-common.