Ppmrainbow User Manual(0)			     Ppmrainbow User Manual(0)



NAME
       ppmrainbow - Generate a rainbow


SYNOPSIS
       ppmrainbow

       [-width=number] [-height=number] [-tmpdir=directory] [-norepeat] [-ver-
       bose] color ...


DESCRIPTION
       This program is part of Netpbm(1).

       ppmrainbow generates a PPM image that fades from one color  to  another
       to  another  from  left to right, like a rainbow.  The colors are those
       you specify on the command line, in that order.	 The  first  color  is
       added again on the right end of the image unless you specify the -nore-
       peat option.

       If you want a vertical or other non-horizontal rainbow, run the	output
       through pnmrotate or pamflip.

       One use for such a rainbow is to compose it with another image under an
       alpha mask in order to add a rainbow area to another image.   In	 fact,
       you  can	 make rainbow-colored text by using pbmtext, pamcomp, and ppm-
       rainbow.

       pgmramp does a similar thing for grayscale images.

       If you just want an image containing all the possible colors (for  some
       kind of processing; not to look at), see pamseq.


OPTIONS
       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	 equals	 signs	between an option name and its
       value.



       -width number
	      The width in pixels of the output image.

	      Default is 600.


       -height number
	      The height in pixels of the output image.

	      Default is 8.


       -norepeat

	      This option makes ppmrainbow end the rainbow with the last color
	      you  specify.   Without  this  option, ppmrainbow adds the first
	      color you specify to the right end of the rainbow as if you  had
	      repeated	it.   (I  don't	 understand  the point of this default
	      behavior; it exists today just for backward compatibility).


       -tmpdir
	      The directory specification of the directory  ppmrainbow	is  to
	      use for temporary files.

	      Default is the value of the TMPDIR environment variable, or /tmp
	      if TMPDIR is not set.


       -verbose
	      Print the 'commands' (invocations of other Netpbm programs) that
	      ppmrainbow uses to create the image.




SEE ALSO
       pgmramp(1), pamseq(1), pamgradient(1), ppmmake(1), ppmfade(1), ppm(1).


AUTHOR
       Arjen  Bax  wrote  ppmrainbow  in  June	2001 and contributed it to the
       Netpbm package.	Bryan Henderson wrote this manual in July 2001.



netpbm documentation		14 October 2005	     Ppmrainbow User Manual(0)