.TL
Pgmramp User Manual
.SH 1
pgmramp
.LP
Updated: 04 June 2002
.br
Table Of Contents
.SH 2
NAME
.LP
pgmramp - generate a grayscale ramp
.SH 2
SYNOPSIS
.LP
\fBpgmramp\fR
\fB-lr\fR|\fB-tb\fR|\fB-rectangle\fR|\fB-ellipse\fR
\fB-maxval=\fR\fImaxval\fR
\fIwidth\fR \fIheight\fR
.LP
All options can be abbreviated to their shortest unique prefix.
You may use two hyphens instead of one to designate an option.  You
may use either white space or an equals sign between an option name
and its value.
.SH 2
DESCRIPTION
.LP
.LP
This program is part of Netpbm.
.LP
Generates a graymap of the specified size containing a
black-to-white ramp.  These ramps are useful for multiplying with
other images, using \fBpamarith\fR.
.LP
The ramp is linear in brightness, not intensity.  I.e. the
gamma-corrected sample values in the PGM rise linearly with distance
from the corner of the image.  If you want a ramp that is linear in
light intensity, use \fBpnmgamma\fR with \fBpgmramp\fR.
.LP
To generate a simple ramp of all the values from 0 to maxval, and not
necessarily a graphic image, use \fBpamseq\fR.
.LP
\fBppmrainbow\fR does something similar to what \fBpgmramp\fR does,
but for color.  The image fades between two colors of your choice.
.SH 2
OPTIONS
.LP
You must specify exactly one of the ramp type options.
.RS
.IP "\fB-lr\fR"
A left to right ramp.
.IP "\fB-tb\fR"
A top to bottom ramp.
.IP "\fB-rectangle\fR"
An outside-in rectangular ramp.  It is black around the edges and white
in the center.
.IP "\fB-ellipse\fR"
An outside-in elliptical ramp.  It is black around the edge and white
in the center.
.IP "\fB-maxval=\fR\fImaxval\fR"
The maxval for the generated image.  Default is 255.
.LP
This option did not exist before June 2002.  Before, the maxval was
always 255.
.RE
.SH 2
SEE ALSO
.LP
\fBpamarith\fR,
\fBpnmgamma\fR,
\fBpamseq\fR,
\fBppmrainbow\fR,
\fBpamgradient\fR,
pgm
.SH 2
AUTHOR
.LP
Copyright (C) 1989 by Jef Poskanzer.
.br
\l'5i'
.SH 2
Table Of Contents
.LP
.IP \(bu
NAME
.IP \(bu
SYNOPSIS
.IP \(bu
DESCRIPTION
.IP \(bu
OPTIONS
.IP \(bu
SEE ALSO
.IP \(bu
AUTHOR
.LP