I'm using Ubuntu 11.10 and my monitor had a problem where Green is the bright colour, there's no way to change it in the monitor settings, so when I was using WinXP (I'm new in here) I changed the green to lower using Video Driver settings, in here (ubuntu) I don't know exactly how I would change the green colour to low, so my "black" would be seem has a real black, no green. Thanks for reading. Sorry for bad English.
1 Answer
You can adjust the individual colour gamma correction settings of your screen using the xgamma
tool. Running it with no arguments will print the current settings:
$ xgamma
-> Red 1.000, Green 1.000, Blue 1.000
You can adjust the green gamma value with a command like:
$ xgamma -ggamma 0.75
If you are using a multi-monitor set up and want to adjust the gamma of individual outputs, you can do so with the xrandr
tool instead:
$ xrandr --output $OUTPUT --gamma $RED:$GREEN:$BLUE
In this command, $OUTPUT
is one of the outputs listed when you run xrandr
with no arguments. Note also that xrandr
treats the gamma mapping as going in the reverse direction, so you will need to provide the inverse of the values you'd provide to xgamma
(e.g. passing 2.0 to xgamma
is equivalent to passing 0.5 to xrandr
).
Both of these options will not survive an X server restart, so once you've got some values you're happy with consider putting them in a shell script (perhaps in ~/bin
), and then adding that script as a startup application.
xgamma
tool (in particular the-ggamma
option). I'm not sure how well this would help with the green brightness for black pixels though.