Personally I would try DPIRdeblock with high values like 75, 100, 150,...
I expect, conventional deblockers to either do nothing noticeable or blur too much.
You might also want to check BasicVSR++, 'NTIRE 2021 (1)' should perform well at such resolutions.
On some scenes, 'Video Deblurring (GoPro)' or 'Video Deblurring (DVD)' might also be worth a look, but probably will seem 'unnatural' in most scenes.
Another thing, independent of what deblocker you choose, might be to try testing what happens if you use CAS (0.7, 0.8.0.9, 1) before the deblocker.
Cu Selur
Ps.: In the future, use i.e. mkvtoolnix to cut yoru source and only share a chuck of it.
Ah, thanks very much for the quality suggestions and recommended settings, Selur!
So, if I understand you correctly, I should first run CAS and then DPIRdeblock, right? (If I chose to execute that combo.)
Gotcha! Yeah, I'll just post selected clips on Google Drive.
I have the latest version of MKVToolNix installed on my ASUS but haven't done any editing with it before. So I can trim and cut scenes with it? Do you know which section/feature performs editing in the app? I'll have to peruse its documentation.
On remuxing MKVtoolnix allows to Split by size other criteria.
It also can Split by a given time, but will only cut on key frames
Cu Selur
Ps.:
Here is an example of a. a cut of the file you linked b. a reencoded version where I used cas 0.9 and BasicVSR++.
Ah, thanks so much for extracting that clip and then producing another one with the two filters applied! I thought that the original looked quite good but after seeing what you did when adding CAS and BasicVSR++, it appears considerably sharper and clearer!
Does it matter that much the order in which I apply the filters?
Yes, the order of filters does matter.
Also note this was just a suggestion, personally I would probably say that BasicVSR++ might be too strong, so I would, try whether applying it 'masked' is a better idea,.. (
https://imgsli.com/NDQ3MTUy,
https://imgsli.com/NDQ3MTU0)
You could also use merge it my percentage and apply different settings to different section.
=> there are tons of way to tweak it, it's mainly a question about how much time is you want to spend on finding settings you like.
Cu Selur