From LG documenation:
“If you connect a device that supports HDMI ULTRA HD Deep Color, you can enjoy a clearer image. After connecting the playback device, set HDMI ULTRA HD Deep Color to On. If the connected device does not support this function, it may not work properly. In that case, change the TV’s HDMI ULTRA HD Deep Color setting to Off.”
Supported Display Resolution
I would assume that the Apple TV 4K supports this feature, but I’m not 100% sure.
“If you connect a device that supports HDMI ULTRA HD Deep Color, you can enjoy a clearer image. After connecting the playback device, set HDMI ULTRA HD Deep Color to On. If the connected device does not support this function, it may not work properly. In that case, change the TV’s HDMI ULTRA HD Deep Color setting to Off.”
Supported Display Resolution
- On : Supports 4K@120 Hz (4:4:4, 4:2:2, and 4:2:0)
- Off : Supports 4K@60 Hz (4:2:0)
I would assume that the Apple TV 4K supports this feature, but I’m not 100% sure.