As the title says, I get strange artifacts with 4k video no matter what settings I use. I tried to output it in 4k as well as downsample to 1440p and 1080p even and there there are still artifacts. Tried out various bitrates from 20 to up to 80 Mbps. Here are some examples:
They are really bad and clearly visible artifacts on the lower right and left side over the roads. As a whole I am not satisfied with the image quality that was produced, although the source is top notch and no artifacts whatsoever.