pnmsmooth (1) - Linux Manuals

pnmsmooth: smooth out an image


pnmsmooth - smooth out an image


pnmsmooth [-size width height] [-dump dumpfile] [pnmfile]


Smooths out an image by replacing each pixel with the average of its width X height neighbors. It is implemented as a C progam that generates a PGM convolution matrix and then invokes pnmconvol.


-size width height
Specifies the size of the convolution matrix. Default size is a 3x3 matrix. Width and height sizes must be odd. Maximum size of convolution matrix is limited by the maximum value for a pixel such that (width * height * 2) must not exceed the maximum pixel value.
-dump dumpfile
Generates and saves the convolution file only. Use of this option does not invoke pnmconvol.


Copyright (C) 1989, 1991 by Jef Poskanzer.
Converted from script to C program December 1994 by Mike Burns (burns [at]


pnmconvol(1), pnm(5)