RGB Hi
I have the Apple 4 K TV, just purchase the LG 65" GX OLED 4K TV.
Should I be using the RGB Hi setting
Question marked as
The video streams are encoded using the YCbCr color space, and your TV accepts YCbCr, thus no conversion is needed by the Apple TV box. YCbCr doesn’t have High and Low variations, so you can’t go wrong there. YCbCr can use less bandwidth than RGB, freeing up more bandwidth for other features (resolution, frame rate, HDR).
- RGB: always 4:4:4 chroma subsampling
- YCbCr: 4:4:4, 4:2:2 (67% bandwidth), or 4:2:0 (50% bandwidth) chroma subsampling. Delivery format video files are always 4:2:0, so 4:4:4 would increase the bandwidth needs without quality improvement. Thus the 4:2:0 chroma setting is recommended. Depending on other settings and content, 4:4:4 might cause other features to be dropped, to keep to bandwidth use under the HDMI 2.0 limits.
The video format settings that are selectable, is what is detected as compatible with the connected hardware. That includes the screen (TV), any equipment in between, the HDMI cables (18 Gbps recommended), the HDMI ports (HDMI 2.0) and the port configuration on the TV and any equipment in between, if applicable.
When done correctly, you can have 4K HDR DV 60 Hz within the bandwidth restrictions of HDMI 2.0.