Pnmpad User Manual(0) Pnmpad User Manual(0)NAMEpnmpad - add borders to a PNM image
SYNOPSISpnmpad [-verbose] [-white|-black] [-width=pixels] [-halign=ratio]
[-left=pixels] [-right=pixels] [-height=pixels] [-valign=ratio]
[-top=pixels] [-bottom=pixels] [pnmfile]
DESCRIPTION
This program is part of Netpbm(1).
pnmpad reads a PNM image as input and outputs a PNM image that is the
input image plus black or white borders of the sizes specified.
If you just need to convert an image to a certain size regardless of
the original dimensions, pamcut with the -pad option may be a better
choice.
pnmmargin does essentially the same thing, but allows you to add bor‐
ders of any color and requires all four borders to be the same size.
OPTIONS
All options can be abbreviated to their shortest unique prefix. You
may use two hyphens instead of one to designate an option. You may use
either white space or an equals sign between an option name and its
value.
-verbose
Verbose output.
-white
-black Set pad color. Default is -black.
-left=pixels
-right=pixels
-width=width
-halign=ratio
Specify amount of left and right padding in pixels.
-left and -right directly specify the amount of padding added to
the left and right sides, respectively, of the image.
Alternatively, you can specify -width and just one of -left and
-right and pnmpad calculates the required padding on the other
side based on the width of the input image. If the -width value
is less than the width of the image plus the specified padding,
the -width values is ignored.
If you specify all three of -width, -left, and -right, you must
ensure that the -left and -right padding are sufficient to make
the image at least as wide as -width specifies. Otherwise, pnm‐
pad fails.
When you specify -width without -left or -right, and -width is
larger than the input image, pnmpad chooses left and right pad‐
ding amounts in a certain ratio. That ratio defaults to half,
but you can set it to anything (from 0 to 1) with the -halign
option. If the input image is already at least as wide as
-width specifies, pnmpad adds no padding.
Common values for -halign are:
0.0 left aligned
0.5 center aligned (default)
1.0 right aligned
Before Netpbm 10.23 (July 2004), pnmpad did not allow the -left
or -right option together with -width.
-top=pixels
-bottom=pixels
-height=height
-valign=ratio
These options determine the vertical padding. They are analo‐
gous to the horizontal padding options above.
HISTORY
Before February 2002, pnmpad had a different option syntax which was
less expressive and not like conventional Netpbm programs. That syntax
is still understood by pnmpad for backward compatibility, but not docu‐
mented or supported for future use.
SEE ALSOpbmmake(1), pnmpaste(1), pamcut(1), pnmcrop(1), pamcomp(1), pnmmar‐
gin(1), pbm(1)AUTHOR
Copyright (C) 2002 by Martin van Beilen
Copyright (C) 1990 by Angus Duggan
Copyright (C) 1989 by Jef Poskanzer.
Permission to use, copy, modify, and distribute this software and its
documentation for any purpose and without fee is hereby granted, pro‐
vided that the above copyright notice appear in all copies and that
both that copyright notice and this permission notice appear in sup‐
porting documentation. This software is provided 'as is' without
express or implied warranty.
netpbm documentation 20 March 2009 Pnmpad User Manual(0)