\
.\" This man page was generated by the Netpbm tool 'makeman' from HTML source.
.\" Do not hand-hack it!  If you have bug fixes or improvements, please find
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.TH "Ppmrelief User Manual" 1 "02 August 2014" "netpbm documentation"

.SH NAME

ppmrelief - compute a relief of a PPM image

.UN synopsis
.SH SYNOPSIS

\fBppmrelief\fP

[\fIppmfile\fP]

.UN description
.SH DESCRIPTION
.PP
This program is part of
.BR "Netpbm" (1)\c
\&.
.PP
\fBppmrelief\fP reads a PPM image as input, and writes a relief of
that image as a PPM image as output.
.PP
The relief process is described in "Beyond Photography" by
Holzmann, equation 3.19.  It's a sort of edge-detection and is essentially
a convolution with this matrix:

.nf

    |  1  0  0 |
    |  0  0  0 |
    |  0  0 -1 |


.fi

.UN options
.SH OPTIONS
.PP
There are no command line options defined specifically
for \fBppmrelief\fP, but it recognizes the options common to all
programs based on libnetpbm (See 
.UR index.html#commonoptions
 Common Options
.UE
\&.)

.UN seealso
.SH SEE ALSO
.BR "pamshadedrelief" (1)\c
\&, 
.BR "pgmbentley" (1)\c
\&, 
.BR "pgmoil" (1)\c
\&, 
.BR "ppm" (1)\c
\&

.UN author
.SH AUTHOR

Copyright (C) 1990 by Wilson Bent (\fIwhb@hoh-2.att.com\fP)
.SH DOCUMENT SOURCE
This manual page was generated by the Netpbm tool 'makeman' from HTML
source.  The master documentation is at
.IP
.B http://netpbm.sourceforge.net/doc/ppmrelief.html
.PP