pnmsmooth

Smooth out a PNM image. More information: https://netpbm.sourceforge.net/doc/pnmsmooth.html.

• Smooth out a PNM image using a convolution matrix of size 3x3:

pnmsmooth path/to/input.pnm > path/to/output.pnm

• Smooth out a PNM image using a convolution matrix of size width times height:

pnmsmooth -width width -height height path/to/input.pnm > path/to/output.pnm