Quick and dirty batch script to watermark and add IPTC data to a set of files in the supplied dir to -Copyright.

#!/bin/bash
# Copyright Andy Wright - www.litost.org 2006.
# You have permission to do what you want with it as long as you don't
# blame me if it insults your mother etc. :).
# Std disclaimers apply.
# Quick and dirty batch script to watermark and add IPTC data to a set of
# files in the supplied dir to -Copyright.

# Needs:
# ImageMagick - http://www.imagemagick.org/
# Exiv2 - http://www.exiv2.org/

CopyrightStr="Copyright String"
CreditStr="Credit String"

Exiv2=/usr/local/exiv2/bin/exiv2
Composite=/usr/bin/composite
CopyrightImg=Copyright.png
Quality=96

inDir=$1
[ -z "$inDir" ] && cat < < EOF && exit 1
Add watermark and IPTC data to all the files in  -> -Copyright
Warning probably only works on relative directories.
Usage: $0 
EOF

outDir=$inDir-Copyright
test -d $outDir || mkdir $outDir

renice 15 -p $$

for file in $(ls -1 $inDir/*.{jpg,JPG} | sed -e "s/^$inDir\///")
do
    infile=$inDir/$file
    outfile=$outDir/$file
    echo "Adding IPTC data to $file"
    $Exiv2 -M"set Iptc.Application2.Copyright String $CopyrightStr" $infile
    $Exiv2 -M"set Iptc.Application2.Credit String $CreditStr" $infile
    $Exiv2 -M"set Iptc.Application2.TransmissionReference String $file" $infile

    echo "Copyrighting $file"
    $Composite -quality $Quality -gravity southeast $CopyrightImg $infile $outfile
done

Source: http://www.litost.org/copyright.sh.txt