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}}