PPMRELIEF

NAME

      ppmrelief - run a Laplacian relief filter on a portable pixmap

SYNOPSIS

      ppmrelief [ppmfile]

DESCRIPTION

      Reads a portable pixmap as input.  Does a Laplacian relief filter, and
      writes a portable pixmap as output.
      The Laplacian relief filter is described in "Beyond Photography" by
      Holzmann, equation 3.19.  It's a sort of edge-detection.

DEMONSTRATION

      Let a.ppm be a portable pixmap.
      The following command will apply a Laplacian filter on it:
	ppmmerge ppmrelief a.ppm > arelief.ppm

BEFORE

AFTER

SEE ALSO

      pgmbentley(1), pgmoil(1), ppm(5)

AUTHOR

      Copyright (C) 1990 by Wilson Bent (whb@hoh-2.att.com)