NAME
pnmsmooth - smooth out an image
SYNOPSIS
pnmsmooth [-width=cols] [-height=rows] [-dump=dumpfile] [pnmfile] [-size]
Minimum unique abbreviations of options is acceptable. You may use double hyphens instead of single hyphen to denote options. You may use white space in place of the equals sign to separate an option name from its value.
DESCRIPTION
This program is part of Netpbm(1)
pnmsmooth smoothes out an image by replacing each pixel with the average of its width X height neighbors. It is implemented as a progam that generates a PGM convolution matrix and then invokes pnmconvol with it.
OPTIONS
-width=cols
-height=rows | |
These options specify the dimensions of the convolution matrix.
Default dimensions are 3 wide and 3 high. Each dimension must be odd.
The maximum size of the convolution matrix is limited by the maxval of
the image such that width * height * 2 must not exceed the maxval.
(use pamdepth to increase the maxval if necessary).
These options were new in Netpbm 10.32 (February 2006). Before that, use -size.
| |
-size | This deprecated option exists in current Netpbm for backward
compatibility. It was obsoleted by -width and -height
in Netpbm 10.32 (February 2006).
When you use this option, the first two program arguments are the width and height, respectively, of the convolution matrix and do the same thing as the -width and -height option values. The third (optional) program argument is the input file name.
In reality, in old pnmsmooth, the width and height are two
values of the -size option, but the modern Netpbm command syntax
paradigm doesnt allow an option with multiple values, so instead
-size is an option with no value and width and height are program
arguments. That has the fortunate effect of making the following command
mean the same in current pnmsmooth as in old pnmsmooth:
|
-dump=dumpfile | |
This options makes pnmsmooth only generate and save the
convolution file. It does not invoke pnmconvol and does not
produce an output image.
| |
SEE ALSO
HISTORY
Before Netpbm 10.32 (February 2006), pnmsmooth did not use the modern Netpbm command line parser, so had an unconventional command line syntax. Most importantly, you could not use an equal size or double hyphens in the options.