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.TH "Pnminvert User Manual" 0 "08 August 1989" "netpbm documentation"

.UN lbAB
.SH NAME

pnminvert - invert a PNM image

.UN lbAC
.SH SYNOPSIS

\fBpnminvert\fP

[\fIpnmfile\fP]

.UN lbAD
.SH DESCRIPTION
.PP
This program is part of
.BR Netpbm (1)
.
.PP
\fBpnminvert\fP reads a PNM image as input, inverts it black for
white, and produces a PNM image as output.
.PP
If the image is grayscale, \fBpnminvert\fP 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.
.PP
If the image is color, \fBpnminvert\fP inverts each individual RGB
component the same as for a grayscale image.

.UN lbAE
.SH SEE ALSO
.BR pnm (5)


.UN lbAF
.SH AUTHOR

Copyright (C) 1989 by Jef Poskanzer.