How to adjust screen settings: contrast, color saturation, etc

using Xubuntu 14.04 with a HP mini notebook.

I can't seem to find any program to adjust screen settings: contrast, brightness, and more importantly: color saturation, tint and gamma.

Thanks beforehand.

Personally, I use terminal commands xgamma for contrast and occasionally xrandr for brightness (though mostly I use the native brightness setting - more on that later ).

To change contrast with xgamma , do

xgamma -gamma $1

Where $1 is a decimal value. It can be 1.5 or .5 , but the values above those values can be harsh on the eyes, so play with the values in that range.

To change brightness with xrandr , you need to know the name of your display. Run xrandr to find that out, should be mentioned as connected primary.

To change brightness, do

  xrandr --output $SCREEN --brightness $VALUE

where $SCREEN is the value of your connected primary and $VALUE is decimal number, again in range from 0 (completely off) to whatever

Personally , what I'd do is spawn gnome-settings-daemon or unity-settings-daemon command , whichever is available, and use the following two commands to change brightness :

qdbus org.gnome.SettingsDaemon.Power /org/gnome/SettingsDaemon/Power org.gnome.SettingsDaemon.Power.Screen.StepUp
qdbus org.gnome.SettingsDaemon.Power /org/gnome/SettingsDaemon/Power org.gnome.SettingsDaemon.Power.Screen.StepDown

( provided of course that you have qdbus installed ; it is so for Default Ubuntu with Unity, but I don't know about Xubuntu . If you don't have the settings daemon, you can install it with sudo apt-get install gnome-settings-daemon )

this can be made with xrandr, first identify you video output running "xrandr" and look into the output sor something like this:

DVI-I-1 connected 1600x900+1600+0 (normal left inverted right x axis y axis)

in my case, my output is DVI-I-1, now i run "xrandr --props" to know what properties can i change.

scaling mode: None 
    supported: None, Full, Center, Full aspect
color vibrance: 180 
    range: (0, 200)
vibrant hue: 90 
    range: (0, 180)
non-desktop: 0 
    range: (0, 1)
link-status: Good 
    supported: Good, Bad

to change the saturation, in my case (Old GeForce GT 520), i run the following:

xrandr --output DVI-I-1 --set "color vibrance" "180"

Hope this works for all you guys.