Grab the EXIF date from original date time field and overlay it on a photo with white text with black stroke font.

EXIFdate2photo.sh

#!/bin/sh
#Credit: http://dptnt.com/2009/08/add-date-time-stamp-to-jpeg-photos-using-free-software-mac-linux-nix-edition/
# I added: 
#     1. formatting the EXIF date to use the month name and remove the seconds from the time display
#     2. outline the text for lighter backgrounds and better contrast in more images.
#Dependencies: imagemagick, exiftool

# Change the font variable to point to your font location
##font="~/Library/Fonts/digital-7 (mono).ttf" 
## digital 7 for to make date time like the *olden days*: http://www.dafont.com/digital-7.font

font="/Library/Fonts/Arial Black.ttf"
## really big system font for sight-impaired relatives :)

if [ $# -eq 0 ]
   then
      cat << _EOF_

USAGE: $0 file1 file2 ..., or
       $0 *.jpg, or
       $0 dir/*.jpg
       ...

_EOF_
      exit
fi

while [ "$1" != "" ]; do
        # Skip directories
        if [ -d "$1" ]; then
                shift
                continue
        fi
        # Skip already converted files (may get overwritten)
        if [[ $1 == *_DT* ]]
        then
                echo "------  Skipping: $1"
                shift
                continue
        fi

        # Work out a new file name by adding "_DT" before file extension
        file=$1
        echo "######  Working on file: $file"
        filename=${file%.*}
        extension=${file##*.}
        output=${filename}_DT.${extension}

        # Get the file dimension
        dim=$(identify -format "%w %h" "$file")
        width=${dim%% *}
        height=${dim#* }

        # Decide the font size automatically, 30 is usually good, but I needed it larger
        if [ $width -ge $height ]
        then
                pointsize=$(($width/75))
        else
                pointsize=$(($height/75))
        fi

        echo "        Width: $width, Height: $height. Using pointsize: $pointsize"
        exifdate=`exiftool -d " %Y-%m-%d %H:%M:%S " -FileModifyDate -S -s "${file}"`
        echo "------  $exifdate"      #sanity check in processing
        # The real deal here
        convert "$file" -gravity SouthEast -font "$font" -pointsize $pointsize -fill white -stroke black -strokewidth 4 -annotate +$pointsize+$pointsize "$exifdate" -stroke none -annotate +$pointsize+$pointsize "$exifdate" "$output"

        shift
done

exit 0