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<H1>pnmalias</H1>
Updated: 15 March 2004
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<A HREF="#index">Table Of Contents</A>
<H2>NAME</H2>
pnmalias - antialias a PNM image
<H2 id="synopsis">SYNOPSIS</H2>
<B>pnmalias</B>
[<B>-bgcolor</B> <I>color</I>]
[<B>-fgcolor</B> <I>color</I>]
[<B>-bonly</B>]
[<B>-fonly</B>]
[<B>-balias</B>]
[<B>-falias</B>]
[<B>-weight</B> <I>w</I>]
[<I>pnmfile</I>]
<H2 id="description">DESCRIPTION</H2>
<p>This program is part of <a href="index.html">Netpbm</a>.
<p><b>pnmalias</b> reads a PNM image as input, and applies
anti-aliasing to background and foreground pixels. If the input file
is a PBM, <b>pnmalias</b> promotes the output anti-aliased image to a
PGM, and prints a message informing the user of the change in format.
<H2 id="options">OPTIONS</H2>
<P><B>-bgcolor</B> <I>colorb</I> sets the background color the
<i>colorb</i>.
<p><B>-fgcolor</B> <I>colorf</I> sets the foreground color to
<i>colorf</i>.
<p>Pixels with these values will be anti-aliased. By default,
<b>pnmalias</b> takes the background color to be black, and foreground
color to be white.
<P>Specify the color (<i>color</i>) as described for the <a
href="libppm.html#colorname">argument of the <b>ppm_parsecolor()</b>
library routine</a>.
<P>Note that even when dealing with PGMs, background and foreground
colors need to be specified in the fashion described above. In this
case, <b>pnmalias</b> takes the background and foreground pixel values
to be the value of the red component for the specified color.
<P><B>-bonly</B> says to apply anti-aliasing only to the background pixels.
<p><B>-fonly</B> says to apply anti-aliasing only to the foreground pixels.
<P><B>-balias</B> says to apply anti-aliasing to all pixels surrounding
background pixels.
<P><B>-falias</B> says to apply anti-aliasing to all pixels surrounding
foreground pixels.
<p>If you specify neither <b>-balias</b> nor <b>-falias</b>,
<b>pnmalias</b> applies anti-aliasing only among neighboring
background and foreground pixels.
<P><B>-weight</B> <I>w</I> says to use <I>w</I> as the central weight
for the aliasing filter. <I>w</I> must be a real number in the range
0 < <I>w</I> < 1. The lower the value of <I>w</I> is, the
"blurrier" the output image is. The default is w = 1/3.
<H2 id="seealso">SEE ALSO</H2>
<A HREF="pbmtext.html">pbmtext</A>,
<A HREF="pnmsmooth.html">pnmsmooth</A>,
<A HREF="pnm.html">pnm</A>
<H2 id="author">AUTHOR</H2>
Copyright (C) 1992 by Alberto Accomazzi, Smithsonian Astrophysical Observatory.
<HR>
<H2 id="index">Table Of Contents</H2>
<UL>
<LI><A HREF="#synopsis">SYNOPSIS</A>
<LI><A HREF="#description">DESCRIPTION</A>
<LI><A HREF="#options">OPTIONS</A>
<LI><A HREF="#seealso">SEE ALSO</A>
<LI><A HREF="#author">AUTHOR</A>
</UL>
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