pbmclean

Clean up a PBM image by erasing isolated black and white pixels. More information: https://netpbm.sourceforge.net/doc/pbmclean.html.

pbmclean path/to/image.pbm > path/to/output.pbm

pbmclean -black|white path/to/image.pbm > path/to/output.pbm

pbmclean -minneighbours 3 path/to/image.pbm > path/to/output.pbm