Using a 2d image resynthesis algorithm is sub-optimal for video. There is basically no chance of it picking the same result every single frame, you will see a f

Using a 2d image resynthesis algorithm is sub-optimal for video. There is basically no chance of it picking the same result every single frame, you will see a flickering shadow of weirdness where the old characters were. You have lots of infomation of what image should be there; You have motion vectors signaling when an object or background has moved into (or out of) a blocked area. Or a maybe the motion vectors indicate object/background is stationary and you can use infomation from before/after the subtitles to fill it in. I'm not aware of such a 3d video resynthesis algorithm existing, but it should be possible.