Were the oil paintings in the episode "Im Schmerz geboren" for real?

One of many unusual aspects of the amazing Tatort episode "Im Schmerz geboren" was the parts where the scene transformed into oil paintings showing stills of the action, as with the casino shootout or the final portrait of all the people who have died.

I wonder, though, to which degree those were actual real paintings drawn by humans or just entirely post-processed stills of the filmed movie. There are aspects, like the live transformation of the real scene into the painting that might suggest that this was just post-processing of the film. In fact other effects, like Harloff's Stendahl-syndrome making him imagine weird things going on in paintings, that seem to be achievable by CGI only. But on the other hand on close-up they look very real with a recognizable linen structure and especially the final portait zooms out into an actual portrait hanging in a museum. There are also enhancements that seem to require manual adjustments anyway, like the very elaborate blood splashes. So how much was there any real oil painting magic involved here, was this all just computer trickery or did someone actually paint this stuff, or was it a kind of mixture between both techniques?