<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 3.2//EN">
<HTML><HEAD><TITLE>Pnminvert User Manual</TITLE></HEAD>
<BODY>
<H1>pnminvert</H1>
Updated: 08 August 1989
<BR>
<A HREF="#index">Table Of Contents</A>
<A NAME="lbAB"> </A>
<H2>NAME</H2>
pnminvert - invert a PNM image
<A NAME="lbAC"> </A>
<H2>SYNOPSIS</H2>
<B>pnminvert</B>
[<I>pnmfile</I>]
<A NAME="lbAD"> </A>
<H2>DESCRIPTION</H2>
<p>This program is part of <a href="index.html">Netpbm</a>.
<p><b>pnminvert</b> reads a PNM image as input, inverts it black for
white, and produces a PNM image as output.
<p>If the image is grayscale, <b>pnminvert</b> replaces a pixel with
one of complementary brightness, i.e. if the original pixel has gamma-adjusted
gray value G, the output pixel has gray value maxval - G.
<p>If the image is color, <b>pnminvert</b> inverts each individual RGB
component the same as for a grayscale image.
<A NAME="lbAE"> </A>
<H2>SEE ALSO</H2>
<A HREF="pnm.html">pnm</A>
<A NAME="lbAF"> </A>
<H2>AUTHOR</H2>
Copyright (C) 1989 by Jef Poskanzer.
<HR>
<A NAME="index"> </A>
<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="#lbAF">AUTHOR</A>
</UL>
</BODY>
</HTML>