xgamma - Alter a monitor's gamma correction through the X server

       Kaleb S. Keithley, X Consortium.
       David Dawes, David Bateman

X Version 11                                      xgamma 1.0.7                                         xgamma(1)

       This  client  changes  the  internal values of the gamma correction for the Xserver. Whether or not these
       values are respected depends on the video drivers.

       The gamma values are passed to the Xserver with 3 decimal places of accuracy.

xgamma allows X users to query and alter the gamma correction of a monitor via the X video mode extension
       (XFree86-VidModeExtension).

       Note  that  the xgamma utility is obsolete and deficient, xrandr should be used with drivers that support
       the XRandr extension.

       If no value for the gamma correction is given via the -gamma or -rgamma/-ggamma/-bgamma  options,  xgamma
       prints the current gamma correction of the display.

DISPLAY To get default host and display number.

       xgamma - Alter a monitor's gamma correction through the X server

-displaydisplay
               This argument allows you to specify the server to connect to; see X(7).

       -screenscreen
               When  multiple  displays  are  configured  as a single logical display, this option allows you to
               select the screen you wish to change.

       -quiet  Silence the normal output of xgamma-help   Print out the `Usage:' command syntax summary.

       -version
               Print out the program version and exit.

       -gammaf.f
               The gamma correction can either be defined as a single value, or separately for  the  red,  green
               and blue components. This argument specifies the gamma correction as a single value.

       -rgammaf.f
               This argument specifies the red component of the gamma correction.

       -ggammaf.f
               This argument specifies the green component of the gamma correction.

       -bgammaf.f
               This argument specifies the blue component of the gamma correction.

xvidtune(1), xrandr(1)

xgamma [-display display] [-screen screen] [-quiet] [-version] [-gamma f.f | [[-rgamma f.f] [-ggamma f.f]
       [-bgamma f.f]]]