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ppmdist(1)


NAME

   ppmdist  - simplistic grayscale assignment for machine generated, color
   images

SYNOPSIS

   ppmdist [-intensity|-frequency] [ppmfile]

DESCRIPTION

   Reads a portable pixmap  as  input,  performs  a  simplistic  grayscale
   assignment intended for use with grayscale or bitmap printers.

   Often  conversion from ppm to pgm will yield an image with contrast too
   low for good printer output.  The program  maximizes  contrast  between
   the gray levels output.

   A ppm input of n colors is read, and a pgm of n gray levels is written.
   The gray levels take on the values 0..n-1, while maxval takes on n-1.

   The mapping from color to stepped grayscale can be performed  in  order
   of   input  pixel  intensity,  or  input  pixel  frequency  (number  of
   repetitions).

OPTIONS

   -frequency    Sort input colors by the number of times  a  color
                 appears  in  the  input,  before mapping to evenly
                 distributed graylevels of output.  -intensity Sort
                 input  colors by their grayscale intensity, before
                 mapping  to  evenly  distributed   graylevels   of
                 output.  This is the default.

BUGS

   Helpful  only  for  images  with  a very small number of colors.
   Perhaps should have been an option to ppmtopgm(1).

SEE ALSO

   ppmtopgm(1), ppmhist(1), ppm(5)

AUTHOR

   Copyright (C) 1993 by Dan Stromberg.

                             22 July 1992                       ppmdist(1)



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