pnminvert(1) - Linux man page
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(1)
Author
Copyright (C) 1989 by Jef Poskanzer.
