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.TH xgamma 1 "xgamma 1.0.7" "X Version 11"
.SH NAME
xgamma - Alter a monitor's gamma correction through the X server
.SH SYNOPSIS
.B "xgamma"
[-display \fIdisplay\fP] [-screen \fIscreen\fP] [-quiet] [-version]
[-gamma f.f | [[-rgamma f.f] [-ggamma f.f] [-bgamma f.f]]]
.SH DESCRIPTION
.PP
.B xgamma
allows X users to query and alter the gamma correction of a monitor via
the X video mode extension (XFree86-VidModeExtension).
.PP
Note that the \fBxgamma\fP utility is obsolete and deficient, \fBxrandr\fP
should be used with drivers that support the \fBXRandr\fP extension.
.PP
If no value for the gamma correction is given via the
.I -gamma
or
.IR -rgamma / -ggamma / -bgamma
options,
.B xgamma
prints the current gamma correction of the display.
.SH OPTIONS
.PP
.TP 8
.B "-display \fIdisplay\fP"
This argument allows you to specify the server to connect to; see \fIX(7)\fP.
.PP
.TP 8
.B "-screen \fIscreen\fP"
When multiple displays are configured as a single logical display, this option
allows you to select the screen you wish to change.
.PP
.TP 8
.B "-quiet"
Silence the normal output of
.B xgamma
.PP
.TP 8
.B "-help"
Print out the `Usage:' command syntax summary.
.PP
.TP 8
.B "-version"
Print out the program version and exit.
.PP
.TP 8
.B "-gamma f.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.
.PP
.TP 8
.B "-rgamma f.f"
This argument specifies the red component of the gamma correction.
.PP
.TP 8
.B "-ggamma f.f"
This argument specifies the green component of the gamma correction.
.PP
.TP 8
.B "-bgamma f.f"
This argument specifies the blue component of the gamma correction.
.SH ENVIRONMENT
.PP
.TP 8
.B DISPLAY
To get default host and display number.
.SH BUGS
.PP
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.
.PP
The gamma values are passed to the Xserver with 3 decimal places of
accuracy.
.SH SEE ALSO
xvidtune(1),
xrandr(1)
.SH AUTHORS
Kaleb S. Keithley, X Consortium.
.br
David Dawes, David Bateman