\
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.TH "Pgmenhance User Manual" 1 "13 January 1989" "netpbm documentation"

.SH NAME

pgmenhance - edge-enhance a PGM image

.UN synopsis
.SH SYNOPSIS

\fBpgmenhance\fP

[-\fIN\fP]

[\fIpgmfile\fP]

.UN description
.SH DESCRIPTION
.PP
This program is part of
.BR "Netpbm" (1)\c
\&.
.PP
\fBpgmenhance\fP reads a PGM image as input, enhances the edges,
and writes a PGM image as output.
.PP
The edge enhancing technique is taken from Philip R. Thompson's
"xim" program, which in turn took it from section 6 of
"Digital Halftones by Dot Diffusion", D. E. Knuth, ACM
Transaction on Graphics Vol. 6, No. 4, October 1987, which in turn got
it from two 1976 papers by J. F. Jarvis et. al.

.UN options
.SH OPTIONS
.PP
In addition to the options common to all programs based on libnetpbm
(most notably \fB-quiet\fP, see 
.UR index.html#commonoptions
 Common Options
.UE
\&), \fBpgmenhance\fP recognizes the following
command line option:


.TP
\fB-\fP\fIN\fP
.sp
The optional \fB-\fP\fIN\fP option should be a digit from 1 to 9.
1 is the lowest level of enhancement; 9 is the highest.  The default
is 9.



.UN seealso
.SH SEE ALSO
.BR "pamedge" (1)\c
\&,
.BR "pgm" (1)\c
\&

.UN author
.SH AUTHOR

Copyright (C) 1989 by Jef Poskanzer.
.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/pgmenhance.html
.PP