pnmcomp
Composite PNM images with transparency
TLDR
Composite images
$ pnmcomp [overlay.pnm] [background.pnm] > [output.pnm]
With alpha mask$ pnmcomp -alpha=[mask.pgm] [overlay.pnm] [background.pnm] > [output.pnm]
Position overlay$ pnmcomp -xoff=[100] -yoff=[50] [overlay.pnm] [background.pnm] > [output.pnm]
SYNOPSIS
pnmcomp [options] overlay background
DESCRIPTION
pnmcomp composites two PNM images by overlaying one on top of another with optional alpha transparency. An alpha mask (PGM file) controls the blending between overlay and background pixels.Position offsets (-xoff, -yoff) control where the overlay is placed on the background. Part of the Netpbm toolkit; superseded by pamcomp in newer versions.
PARAMETERS
OVERLAY
Foreground image.BACKGROUND
Background image.-alpha FILE
Alpha mask.-xoff PIXELS
X offset.-yoff PIXELS
Y offset.-align POS
Alignment.
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
CAVEATS
Part of Netpbm. Use pamcomp for newer version.
HISTORY
pnmcomp is part of Netpbm for image compositing.