kgamma5 4:5.12.0-0ubuntu1 (amd64 binary) in ubuntu bionic

 This package contains a settings panel for adjusting the brightness, contrast,
 and gamma-correction of a monitor. Test patterns are shown to help
 determine the settings that accurately display the full range of colors.
 .
 Each of the red, green, and blue components can be adjusted individually,
 or all three components can be adjusted together.