Nice and easy watermarking with imagemagick on a directory with a given mask

watermark.sh

#!/bin/bash

#  _       _____  ________________  __  ______    ____  __ __
# | |     / /   |/_  __/ ____/ __ \/  |/  /   |  / __ \/ //_/
# | | /| / / /| | / / / __/ / /_/ / /|_/ / /| | / /_/ / ,<
# | |/ |/ / ___ |/ / / /___/ _, _/ /  / / ___ |/ _, _/ /| |
# |__/|__/_/  |_/_/ /_____/_/ |_/_/  /_/_/  |_/_/ |_/_/ |_|

OUTDIR=${3:-/tmp}
MASK=${2:-mask.png}

# Set field separtor to ignore spaces in files when expanding
IFS=$(echo -en "\n\b");

echo "Using $MASK and outputing to $OUTDIR";
for file in $1/*; do
    echo "Watermarking $file";
    composite -gravity center $MASK "$file" $OUTDIR/`basename $file`;
done

unset $IFS;