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<H1>pamsharpmap</H1>
Updated: 07 February 2004
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<A HREF="#index">Table Of Contents</A>
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<H2>NAME</H2>
pamsharpmap - create map of sharpness in a PNM/PAM image
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<H2>SYNOPSIS</H2>
<B>pamsharpmap</B> [<I>imagefile</I>]
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<H2>DESCRIPTION</H2>
<p>This program is part of <a href="index.html">Netpbm</a>.
<p><b>pamsharpmap</b> reads a Netpbm image (PNM or PAM) and produces
an image that shows how sharp it is at each location.
<p>Sharpness is a measure of how suddenly (in space) colors change in
the image. <b>pamsharpmap</b> computes the sharpness of each
component color (R, G, B) separately and produces a pixel whose
intensity of each component color is directly proportional to the
sharpness of that component color at the same location in the input
image. Thus, at a point where the image is very sharp in its red and
green components, but dull in its blue component, you will see a
yellow pixel in the output.
<p><b>pamsharpmap</b> computes sharpness at a point simply as the
average difference in intensity between the pixel at that point and
the 8 pixels surrounding it.
<p>At the edges of the image, where there are not 8 pixels surrounding
a pixel, <b>pamsharpmap</b> assumes the image is extended with a black
border.
<p><b>pamsharpmap</b> assumes that the image is a PNM or PNM
equivalent PAM. If it isn't, the results are not necessarily
meaningful.
<p>The output image is the same dimensions, depth, and tuple type as
the input, and has maxval 255.
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<H2>SEE ALSO</H2>
<B><A HREF="pamsharpness.html">pamsharpness</A></B>,
<B><A HREF="pammasksharpen.html">pammasksharpen</A></B>,
<B><A HREF="pamedge.html">pamedge</A></B>,
<B><A HREF="pam.html">pam</A></B>,
<B><A HREF="pnm.html">pnm</A></B>
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<h2>HISTORY</h2>
<p><b>pamsharpmap</b> was added to Netpbm in Release 10.21 (March
2004). Bryan Henderson derived it from the program <b>pnmsharp</b> by
B.W. van Schooten and distributed as part of the Photopnmtools
package.
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<H2>Table Of Contents</H2>
<UL>
<LI><A HREF="#lbAB">NAME</A>
<LI><A HREF="#lbAC">SYNOPSIS</A>
<LI><A HREF="#lbAD">DESCRIPTION</A>
<LI><A HREF="#lbAE">SEE ALSO</A>
<LI><A HREF=#history>HISTORY</A>
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