ppmbrighten(1)                                     ppmbrighten(1)

       ppmbrighten  -  change an images Saturation and Value from
       an HSV map

       ppmbrighten [-n] [-s  <+-  saturation>]  [-v  <+-  value>]

       Reads a portable pixmap as input.  Converts the image from
       RGB space to HSV space and changes the Value by <+- value>
       as  a percentage.  Likewise with the Saturation.  Doubling
       the Value would involve

       ppmbrighten -v 100

       to add 100 percent to the Value.

       The 'n' option normalizes the Value to exist between 0 and
       1 (normalized).

       pgmnorm(1), ppm(5)

       Copyright  (C)  1990 by Brian Moffet Copyright (C) 1989 by
       Jef Poskanzer.

       Permission to use, copy, modify, and distribute this soft-
       ware and its documentation for any purpose and without fee
       is hereby  granted,  provided  that  the  above  copyright
       notice  appear  in all copies and that both that copyright
       notice and this permission  notice  appear  in  supporting
       documentation.   This software is provided "as is" without
       express or implied warranty.

       This program does not change the number of colors.

                           20 Nov 1990                          1