.TH ppmrelief 1 "11 January 1991"
.IX ppmrelief
.SH NAME
ppmrelief - run a Laplacian relief filter on a portable pixmap
.SH SYNOPSIS
.B ppmrelief
.RI [ ppmfile ]
.SH DESCRIPTION
Reads a portable pixmap as input.
Does a Laplacian relief filter, and writes a portable pixmap as output.
.IX "Laplacian relief"
.PP
The Laplacian relief filter is described in "Beyond Photography" by Holzmann,
equation 3.19.
It's a sort of edge-detection.
.IX "edge detection"
.SH "SEE ALSO"
pgmbentley(1), pgmoil(1), ppm(5)
.SH AUTHOR
Copyright (C) 1990 by Wilson Bent (whb@hoh-2.att.com)
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