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<H1>ppmrelief</H1>
Updated: 02 August 2014
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<A HREF="#index">Table Of Contents</A>
<H2>NAME</H2>
ppmrelief - compute a relief of a PPM image
<H2 id="synopsis">SYNOPSIS</H2>
<B>ppmrelief</B>
[<I>ppmfile</I>]
<H2 id="description">DESCRIPTION</H2>
<p>This program is part of <a href="index.html">Netpbm</a>.
<p><b>ppmrelief</b> reads a PPM image as input, and writes a relief of
that image as a PPM image as output.
<P>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:
<pre>
<tt>
| 1 0 0 |
| 0 0 0 |
| 0 0 -1 |
</tt>
</pre>
<H2 id="seealso">SEE ALSO</H2>
<A HREF="pamshadedrelief.html">pamshadedrelief</A>,
<A HREF="pgmbentley.html">pgmbentley</A>,
<A HREF="pgmoil.html">pgmoil</A>,
<A HREF="ppm.html">ppm</A>
<H2 id="author">AUTHOR</H2>
Copyright (C) 1990 by Wilson Bent (<A
HREF="mailto:whb@hoh-2.att.com">whb@hoh-2.att.com</A>)
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<H2 id="index">Table Of Contents</H2>
<UL>
<LI><A HREF="#synopsis">SYNOPSIS</A>
<LI><A HREF="#description">DESCRIPTION</A>
<LI><A HREF="#seealso">SEE ALSO</A>
<LI><A HREF="#author">AUTHOR</A>
</UL>
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