Pnminvert User Manual(0)                              Pnminvert User Manual(0)



NAME
       pnminvert - invert a PNM image


SYNOPSIS
       pnminvert

       [pnmfile]


DESCRIPTION
       This program is part of Netpbm(1)

       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.


SEE ALSO
       pnm(5)



AUTHOR
       Copyright (C) 1989 by Jef Poskanzer.

netpbm documentation            08 August 1989        Pnminvert User Manual(0)