NAME

       pnmcrop - crop a portable anymap

SYNOPSIS

       pnmcrop [-white|-black|-sides] [-left] [-right] [-top] [-bottom] [pnmfile]

       All  options  may  be abbreviated to their shortest unique prefix or specified with double
       hyphens.

DESCRIPTION

       Reads a PBM, PGM, or PPM image as input.  Removes borders that are the  background  color,
       and produces the same type of image as output.

       If you don't specify otherwise, pnmcrop assumes the background color is whatever color the
       top left and right corners of the image are and if they are  different  colors,  something
       midway  between  them.   You  can  specify  that the background is white or black with the
       -white and -black options or make pnmcrop base its guess on all four  corners  instead  of
       just two with -sides.

       By  default, pnmcrop chops off any stripe of background color it finds, on all four sides.
       You can tell pnmcrop to remove only specific borders with the  -left,  -right,  -top,  and
       -bottom options.

       If you want to chop a specific amount off the side of an image, use pnmcut.

       If  you  want  to  add  different  borders after removing the existing ones, use pnmcat or
       pnmcomp.

OPTIONS

       -white Take white to be the background color.  pnmcrop removes borders which are white.

       -black Take black to be the background color.  pnmcrop removes borders which are black.

       -sides Determine the background color from the colors of the four  corners  of  the  input
              image.  pnmcrop removes borders which are of the background color.

              If at least three of the four corners are the same color, pnmcrop takes that as the
              background color.  If not, pnmcrop looks for two corners of the same color  in  the
              following  order, taking the first found as the background color: top, left, right,
              bottom.  If all four corners are different colors, pnmcrop assumes  an  average  of
              the four colors as the background color.

              The -sides option slows pnmcrop down, as it reads the entire image to determine the
              background color in addition to the up to three times that it would read it without
              -sides.

       -left  Remove any left border.

       -right Remove any right border.

       -top   Remove any top border.

       -bottom
              Remove any bottom border.

       -verbose
              Print  on  Standard  Error  information about the processing, including exactly how
              much is being cropped off of which sides.

SEE ALSO

       pnmcut(1), pnmfile(1), pnm(5)

AUTHOR

       Copyright (C) 1989 by Jef Poskanzer.

                                          18 March 2001                                pnmcrop(1)