The solution is to remove the black bars in the frames. The black bars introduce a ghosting effect under some conditions, resulting in vague horizontal lines.

I now use the following procedure:

I start from the PAL versions of the GOUT.

1) Convert the dvd to a high quality mkv (8000kbps) without the black bars, resulting in a 720x326 video. I use Handbrake for the conversion.

2) Apply the super resolution algorithm in Infognition, and upscale to 2160x1296, with the actual video size 2160x815. This will also reintroduce the black bars (this does not affect the super resolution). The output is raw video (avi), so the file is very large (600GB). You can also use compression codecs you can download via the Infognition site. However, I prefer to post-process the upscaled video in Handbrake.

3) Convert the raw video to a mkv file with the proper size (1920x1080, 80000kbps) using Handbrake, resulting in a 20GB per movie HD GOUT.

In all the steps I copy the original audio, so it's an exact copy of the GOUT PAL soundtrack.