Forcing YUV420 ColorMode

Hi all

I run two 4k@60hz Screens on my 1080 Card, a Philips 40 inch Screen and a Samsung 40 inch TV. The Samsung TV is actually over 20m cable. In order to get an image on my HDMI TV, i had to reduce the ColorSpace from FullRGB to Yuv420.

The Nvidia-Settings although have a property, where the ColorSpace can be set, but it only offers FullRGB or Yuv422.

I then found out, that there is an option in nvidia-xconfig:
https://www.freebsd.org/cgi/man.cgi?query=nvidia-xconfig&manpath=ports&sektion=1

nvidia-xconfig --force-yuv-420

This actually alters the xorg.conf file and adds ForceYUV420=TRUE and forces the ColorSpace to the desired value.

Unfortunately, there seems to be no official documentation on ForceYUV420 available, and I don’t know if this is an experimental feature, that could be removed one day?

Does anybody has more information about this option?

Regards
Daniel

Please go through :

Option “ModeValidation” “string”
Option “ColorSpace” “string”
Option “ColorRange” “string”

help at http://us.download.nvidia.com/XFree86/Linux-x86_64/381.09/README/xconfigoptions.html