How to set limited RGB display (pixel format)?

Hi.

Most people want to set full RGB on ubuntu for various reasons. I want to lower it down to display limited RGB because it is easier on the eyes (I’m coming from Windows, hence the terminology; I do not know if some other terms are used for full/limited RGB in the linux world). Please could someone share the commands/scripts for it? I tried the basic xrandr command and below is the output of the same:

xrandr
Screen 0: minimum 320 x 200, current 1920 x 1080, maximum 16384 x 16384
eDP connected primary 1920x1080+0+0 (normal left inverted right x axis y axis) 309mm x 174mm
1920x1080 60.02*+ 40.00
1680x1050 60.02
1280x1024 60.02
1440x900 60.02
1280x800 60.02
1280x720 60.02
1024x768 60.02
800x600 60.02
640x480 60.02
HDMI-A-0 disconnected (normal left inverted right x axis y axis)
DisplayPort-0 disconnected (normal left inverted right x axis y axis)

I’m on an HP laptop (no external display connected).

Thx,
Rohit

Hi @Rohit .
xrandr usage is here

https://xorg-team.pages.debian.net/xorg/howto/use-xrandr.html

Regards
Neville

And can someone explain why this https line would not lookup properly? I had to backquote it to get it to display raw. See below

https://xorg-team.pages.debian.net/xorg/howto/use-xrandr.html

Thank you @nevj for the reply.

However, I don’t find the answer to my question there. I am looking for a way to get limited RGB output on my screen. I don’t see any command/instruction which does that, on that page.

Best,
Rohit

@Rohit , I thought by limited rgb you meant reduced resolution?
Apparently you meant something else?
xrandr can alter the resolution
Neville

OK I looked it up. You want to change the ranges from 0-255 to something less

My feeling is, dont change the monitor, do it in whatever program you are using to generate the display

@nevj True. Resolution change is easy in Ubuntu/Mint etc. Very simple. I am indeed looking forward to lower down the RGB to 16-235 from the full RGB 0-255. It is easier on the eyes that way, if you’re doing office work (for movies/games etc., yes Full RGB is preferred).

Precisely because I am not changing the actual physical monitor, I just want to do it via the display program. In my Win PC it can be done easily. It has an on-board AMD card and its driver/control centre program in Windows lets you do it. There must be a way to do the same in Linux/Ubuntu too.

Oh, BTW, I’m now on Ubuntu Studio which you recommended. It is excellent and songs/videos are surely better than any other distro I’ve used so far. Though not as good as Windows, but still impressive for a Linux distro. I also learned how to update Kernel by downloading package files and depedencies. I have the 5.16 kernel now (had to do it because I’ve realtek wifi card which is not yet supported by current versions)!

BTW, hehe, you are the same Neville who wanted to get into Julia, right? :wink:

I like itsfoss community – so many simple, easy solutions! It has made me more confident about using Linux for long term. And I am not doing any programming/coding; just general purpose usage. Linux is the way forward if you want security, privacy, stability, speed and freedom! Kudos to you all!!

Best,
Rohit

2 Likes

@Rohit
Yes same neville
I have started doing some programs with Julia. Just simple things to get me started. It is a hard road getting proficient in a new language.
The work pattern for Julia is not easy to get used to.

Will think about your limited rgb issue in linux. We need to just search around until we find where it can be set. There is a real technique to this searching for computing solutions. You will get there if you practice. A bit of thinking outside the square usually helps.

Dont change the monitor. You might look and see if Studio will change it. If not there might be a filter you can insert between Studio and the screen drivers.

Studio news is great. There is heaps of good software around, just finding out that it exists can be a challenge. The apt system will search for things, but packets often have poor descriptions of what they can do.

Will keep looking
Neville

@nevj Well, good luck with Julia. I’ve no idea of the programming languages. Never worked in that field.

Yes, I know about the searching thing. Been doing it for like 15+ years [uncle category chap here :slight_smile: ]. But now I’m just too tired (and lazy as well) of it and since itsfoss has active, knowledgeable people, thought about just asking here and maybe someone will reply back.

Thanks again for the help. Yes, I checked on discover but its not of much help. I’m looking for ways to enable hibernation feature (via GUI, not scripts/commands) as well, but that is not that simple either.

Best,
Rohit

@Rohit ,
I found this

Need to check whether you have Xorg or Wayland.
Not GUI I am afraid.

Sorry about the searching thing. I thought you were a newcomer.

I still think you ought to check Studio to see if it will make limited RGB output

Regards
Neville

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@nevj Thank you Neville. I had run into that link too and tried running the command. Ended up with an error, hence this thread here…

I do have Xorg and when the command is customized for my display, I get the following error:

xrandr --output eDP --set “Broadcast RGB” “Limited 16:235”
X Error of failed request: BadName (named color or font does not exist)
Major opcode of failed request: 140 (RANDR)
Minor opcode of failed request: 11 (RRQueryOutputProperty)
Serial number of failed request: 35
Current serial number in output stream: 35


No worries.

Sorry. This simple request is getting too long…

Update: What I am trying to change is called pixel format.

Wonder if we should ask someone else. Can @Akito , @Mina help?

@Rohit If I knew, I would have already answered. No need for tagging.

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@Mina Ok, got it. thx.

1 Like