Is there a difference beween RGB limited and YCbCr444 for HDTV's?

[spiroth10]

I am connected to a TV that only supports limited range,

and as far as I can tell -- RGB Limited and YCbCr444 output just about the same quality image as one another. I switch once in awhile, but the differences are so subtle -- if even there at all -- that I truly cannot tell the difference.

I was wondering if anyone knew if one was technically better for the application than the other?

is YCbCr better for some TV's than RGB Limited -- or if they both work are they equal?

I know the formatting is different, but what about the output quality?

I find it VERY difficult to find any technical answers on this -- I've googled, asked on reddit, and sought the answer elsewhere to no avail.

All I get is "RGB FTW!!!!!!" and thats it, nobody will explain it properly and give a "why".

I think, since its in the GFX card options, there MUST be a case in which it is preferable to RGB Limited -- but it is almost impossible to really know!

[Asmodian]

It is really impossible to know technically without knowing what happens inside the TV.

Assuming the TV never converts to YCbCr in its internal processing RGB is technically better. The screen is native RGB, or maybe RGBY or RGBW, humans cannot actually view YCbCr.

Sadly this assumption is usually not true, but again we don't know what the TV actually does to the video. Even if it converts to YCbCr 4:2:2 or maybe YCbCr 4:4:4 internally for some reason it might still be better to feed it RGB. Any >8-bit RGB to YCbCr 4:4:4 conversion is likely undetectable using normal calibration equipment or test patterns, though if it was done in 8-bit gradient banding tests should show it. It is so unknown, technically it is dependent on the exact model and probably the firmware version, which is why RGB FTW!! is a reasonable answer. :(

[huhn]

outputting limited range should be technically better than outputting YCbCr.

full range RGB to limited range RGB should add less error than full range RGB to YCbCr. but the ranges of YCbCr and lmited RGB are different so who knows...

TVs that support full range RGB at all refreshrates for the win. it's that easy.

[spiroth10]

one forum mentioned that it compressed RGB in the same way, as to make up for the limited RGB and make it more full range. they were saying that it made up for the lack of support of RGB full.

however this logically didnt make sense to me, as I thought it was the ability to output color and contrast that limited RGB, not the type of input algorithm

this is probably just garbage and untrue -- as even though its a different way of encoding the colors, I doubt it can do anything to change the TV itself.

unless of course, the HDMI cable->TV had more to do with it -- but then HDMI PC monitors would be limited RGB too

oh well -- it looks fine on YCbCr for me, and RGB limited looks fine too, so I'll just leave it.

[huhn]

have you even check if your TV can't do full range RGB and is 4:4:4 in the first place?

most TV can do this in PC mode.

[feisty2]

"RGB limited", this thing does exist?

[foxyshadis]

Unfortunately. It's a strange, pointless perversion TV manufacturers have come up with to make the viewing experience even worse.

[huhn]

that's the first thing you have to figure out before you can calibrated your screen.

https://pcmonitors.info/wp-content/uploads/2012/10/AMD-Color-Pixel-Format.png

[feisty2]

okay, whatever that weird studio RGB is, I'm 100% sure no video studio will ever use something like that, and it's limited like how, luma style limit (16-235 at uint8) or chroma style limit (16-240 at uint8) or other insane range?

[huhn]

limited range RGB is just RGB at 16-235 unlike YCbCr with Y 16-235 and Cb/Cr at 16-240.

a TV at default setting usually treats a RGB input as limited range RGB ( it should be 100% of all TVs).

that's part of the totally broken HDMI/DP spec. it was possible to set the output with AMD and it took years to do the same with nvidia and intel. so a tool from madshi was needed to get full range RGB on intel and nvidia for TVs that where changed to full range RGB but the EDID was still the old where the GPU thinks it was limited range or for mis detections of some monitors.

[pandy]

In HDMI all video should be inside limited quantization range and occasional under/overshoots are acceptable, side to this HDMI source can signal full quantization range but this seem to be not fully inline with HDMI spec. In DVI mode only full quantization range is allowed (but YCbCr is not allowed).
IMHO unless digital source can provide clean path for data (no processing) there is no sense for YCbCr as usually some video conversion is unavoidable (some processing can be more convenient in different color space than native - valid for "smart" things where usually RGB OSD graphics need to be combined with YCbCr).
Side to this lot of silicone vendors is incapable to provide correct color space conversion (usually they providing accuracy around 0.2 - 0.5%) - and this is minor problem when you see how incorrectly video can be processed by various chips (imagine chroma trap filter on RGB outputs for example).