How do I adjust the screen contrast?

Question

I am using an Acer Aspire 3680 with Intel GMA 950 video running Ubuntu 16 and I cannot find the command to adjust the screen contrast setting. Too many colors and grays are washed out on the current setting.

What command or graphical utility will do this?

Solution 1

On command line (Terminal), try writing

xgamma -gamma 0.3

You should see a very noticeable difference. Experiment with different values. 1.0 is normal value. Setting a lower gamma will increase the contrast of bright values (decrease white washing), and setting a higher gamma will increase the contrast of dark values (but increase white washing).

Solution 2

maybe you can try "xcalib".

sudo apt-get install xcalib

default(clear):

xcalib -c

Load ICC file:

xcalib ICC_file.icc

adjust contrast:

xcalib -co 70 -a

PS. number means percentage, -a means alter if you want to adjust more, ask "man"! lol

man xcalib

hope that is helpful!!

Solution 3

I had no luck with xgamma, compizconfig-settings-manager or xcalib.

In the end, I was able to use xrandr to successfully change my screen's contrast (and other settings).

This was on an MSI laptop with an Nvidia Geforce GTX graphics card.

---

To install:

sudo apt-get update
sudo apt-get install x11-xserver-utils

---

First run xrandr to see the available screens. eDP-1-1 is the only connected screen in my case. Then run xrandr --output <your screen> --gamma r:g:b

See below for my terminal's output.

$ xrandr
Screen 0: minimum 8 x 8, current 1920 x 1080, maximum 32767 x 32767
HDMI-0 disconnected (normal left inverted right x axis y axis)
DP-0 disconnected (normal left inverted right x axis y axis)
DP-1 disconnected (normal left inverted right x axis y axis)
eDP-1-1 connected primary 1920x1080+0+0 (normal left inverted right x axis y axis) 344mm x 193mm
   1920x1080     60.01*+  59.93  
   1680x1050     59.95    59.88  
   1600x1024     60.17  
   ...
   ...
   512x384       60.00  
   400x300       60.32    56.34  
   320x240       60.05  

$ xrandr --output eDP-1-1 --gamma 0.8:0.8:0.8

Solution 4

I have written a gui front-end for xcalib, which can be found on https://github.com/Ablinne/kolorcontrol.

It provides sliders for brightness/color and gamma for red/green and blue channels respectively. It will display the commands for an autostart script.

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Comments

[CyberSkull]

@Videonauth This question is a year older.

[Videonauth]

and you hadn't had the chance to pick a correct answer for your problem to accept?

[CyberSkull]

Nothing had worked so far on that model. I don’t have regular access to the machine to check anymore.

[CyberSkull]

Where are the icc profiles kept?

[CyberSkull]

Well, it does something, but it is not fixing the contrast issues.

[Admin]

This works only for current session. When I restart again it doesnot work

[CyberSkull]

That is… not useful in my situation.

[Sepero]

Sorry. There are 2 ways to adjust contrast 1) On the physical monitor settings 2) With the graphics card software settings. Here is a link with similar issue, hopefully it help: superuser.com/questions/96539/…

[user2081405]

I installed xcalib and it seems to only decrease contrast: "xcalib -co 80 -a" decreased it, "xcalib -co 100 -a" left it unchanged, "xcalib -co 90 -a" decreased it some more... It seems multiplicative rather than on an absolute scale, but trying numbers >100 gives an error. Help? How can I get my original contrast back?

[anaik]

You can get the original contrast back by using xcalib -c. I got really spooked after the screen went grey on trying xcalib -co 70 -a :P

[Videonauth]

If a link to another answer on Ask Ubuntu contains the answer you would be better of flagging the question as a duplicate

[ASWIN VENU]

Gamma is not contrast