I just came cross this post/thread as ist exactly describes my problem:
That is, especially covers in thumbnail/wall library view look very pixelated and poorly scaled on my 4K TV. I have already set the resolution settings to 999999 in advancedsetings.xml and rescraped everything after clearing the texture cache, but this didn’t help.
Maybe the fix described in this thread can be backported to the Vero? I have now three in my household and absolutely love them. But the artwork display sometimes just looks poor. I understand it is a general Kodi issue. Thanks!
I think there is a condition in which the sixth 9 breaks that setting (I am actually being serious here in case your wondering). That being said that setting is a bad idea under most conditions. I would guess that the place to start would be to actually check the thumbnail folder to see what resolution is actually getting saved. The option does work when everything is done correctly. By default OSMC does actually reduce the artwork size below Kodi defaults for performance reasons (at least I assume this is the motivation) but I have changed this on some of my boxes and confirmed my updated resolution is being used.
You’ve actually linked to the answer to your question already:
At some point, this has been discussed in our team before as well and unfortunately, the remark made on the Kodi forum is true. Only the hardware scaling approach would help improve Kodi image and GUI scaling, but Kodi doesn’t support OpenGL ES which our platform only offers.
So, your approach won’t yield any proper improvements, I’m afraid
It’s possible to run the UI at a real 4K resolution; but this incurs a significant performance penalty.