There's many ways to skin that cat - assuming Unix, immediate options include:

the images are stored locally, you have some mapping from filename to title, and you create new images with watermarks using ImageMagick in a bash script

or the images are hosted online, and you write a small C/Python/whatever code that gets the URLs and associated titles from the host, and then uses Imlib2 (maybe with some wrapper) to display the images with titles rendered as text composited on top

Yea I was trying to find a way to do it with code that's by default shipped on the mac. Unfortunately imagemagick is not. And the php functions to actually add text to an image are not loaded by default. Maybe I can do something by converting the images to pdfs. The speed of the program isn't an issue it just has to be completely automated.

finally found a way to do it with applescript objective c :)

I used a script that relied on Imagemagick.