pgmdeshadow
attempts to compensate for uneven lighting or shadows in scanned
TLDR
Remove uneven lighting from scan
$ pgmdeshadow [input.pgm] > [output.pgm]
SYNOPSIS
pgmdeshadow [file]
DESCRIPTION
pgmdeshadow attempts to compensate for uneven lighting or shadows in scanned images by analyzing and normalizing local brightness. Part of Netpbm toolkit.
INSTALL
sudo apt install netpbm
sudo dnf install netpbm
sudo pacman -S netpbm
sudo apk add netpbm
sudo zypper install netpbm
brew install netpbm
nix profile install nixpkgs#netpbm