# pnminvert

Updated: 08 August 1989
Table Of Contents

## NAME

pnminvert - invert a PNM image

## SYNOPSIS

pnminvert [pnmfile]

## DESCRIPTION

This program is part of Netpbm.

pnminvert reads a PNM image as input, inverts it black for white, and produces a PNM image as output.

If the image is grayscale, pnminvert 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.

If the image is color, pnminvert inverts each individual RGB component the same as for a grayscale image.

## OPTIONS

There are no command line options defined specifically for pnminvert, but it recognizes the options common to all programs based on libnetpbm (See Common Options.)

## SEE ALSO

pnm

## AUTHOR

Copyright (C) 1989 by Jef Poskanzer.

## Table Of Contents

- SYNOPSIS
- DESCRIPTION
- OPTIONS
- SEE ALSO
- AUTHOR