NAME

       pnmarith - perform arithmetic on two portable anymaps

SYNOPSIS

       pnmarith -add|-subtract|-multiply|-difference|-minimum|-maximum.  pnmfile1 pnmfile2

DESCRIPTION

       Reads  two  portable  anymaps  as  input.   Performs  the  specified arithmetic operation, and produces a
       portable anymap as output.  The two input anymaps must be the same width and height.

       The arithmetic is performed between corresponding pixels in the two anymaps, as if maxval was 1.0,  black
       was 0.0, and a linear scale in between.  Results that fall outside of [0..1) are truncated.

       The  operator  -difference calculates the absolute value of pnmarith -subtract pnmfile1 pnmfile2, i.e. no
       truncation is done.

       All flags can be abbreviated to their shortest unique prefix.

SEE ALSO

       pbmmask(1), pnmpaste(1), pnminvert(1), pnm(5)

AUTHOR

       Copyright (C) 1989, 1991 by Jef Poskanzer.  Lightly modified by Marcel Wijkstra <wijkstra@fwi.uva.nl>

                                                 26 August 1993                                      pnmarith(1)