They won't tell you it's NNs but it is. Sony distributes a lot of movies, they use their database of movies to train the upscaling models (which is obviously NNs https://github.com/nagadomi/waifu2x ) and then put the chip in the TV.
It's something almost equivalent to storing Pride and Prejudice and Zombies in your TV in 4K, and then reproducing it when they match it with what's playing on TV.
I don't quite understand what you mean by: "It's something almost equivalent to storing Pride and Prejudice and Zombies in your TV in 4K, and then reproducing it when they match it with what's playing on TV."
Can you explain? What exactly do they have to store in the TV?
Imagine they stored all of the movies they distribute in 4K in your TV. Whenever the movie is displayed they just find it in the database and reproduce the 4K version.
Of course, that is very much infeasible, it requires too large of a storage.
What they do is something like Waifu2x I linked, they train a neural network to learn how to properly upscale movies. They put the "algorithm" on the chip, and its fast enough for real time usage.
When you see side-by-side for these upscalers, it's obvious they aren't that good in deterministic upscaling.