Ppmrainbow User Manual(0) Ppmrainbow User Manual(0)NAMEppmrainbow - Generate a rainbow
SYNOPSISppmrainbow
[-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 ALSOpgmramp(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)
