45

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?

CyberSkull
  • 612

4 Answers4

48

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).

PkP
  • 909
21

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!!

Clark
  • 211
6

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
ethaning
  • 161
  • 1
  • 4
5

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.

Sunday
  • 803