CentOS 7.0 - man page for pgmramp (centos section 0)

Pgmramp User Manual(0)							   Pgmramp User Manual(0)

NAME
       pgmramp - generate a grayscale ramp

SYNOPSIS
       pgmramp -lr|-tb|-rectangle|-ellipse -maxval=maxval width height

       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.

DESCRIPTION
       This program is part of Netpbm(1)

       Generates  a  graymap of the specified size containing a black-to-white ramp.  These ramps
       are useful for multiplying with other images, using pamarith.

       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 pnmgamma with pgmramp.

       To generate a simple ramp of all the values from  0  to	maxval,  and  not  necessarily	a
       graphic image, use pamseq(1)

       ppmrainbow  does  something  similar to what pgmramp does, but for color.  The image fades
       between two colors of your choice.

OPTIONS
       You must specify exactly one of the ramp type options.

       -lr    A left to right ramp.

       -tb    A top to bottom ramp.

       -rectangle
	      An outside-in rectangular ramp.  It is black around the edges and white in the cen-
	      ter.

       -ellipse
	      An  outside-in  elliptical ramp.	It is black around the edge and white in the cen-
	      ter.

       -maxval=maxval
		   The maxval for the generated image.	Default is 255.

		   This option did not exist before June 2002.	Before, the maxval was
		   always 255.

SEE ALSO
       pamarith(1) , pnmgamma(1) , pamseq(1) , ppmrainbow(1) , pamgradient(1) , pgm(1)

AUTHOR
       Copyright (C) 1989 by Jef Poskanzer.

netpbm documentation			   04 June 2002 		   Pgmramp User Manual(0)