In publisher module when you create a clone it create a new PNG logo with the new name.
It uses some php functions like: "imagecreatefrompng", "imagecolorallocate", ...
customization:
If you add it english users can customize their module images contain characters.
localization:
Also non english users can create their own images just by a single click .
Please read more here and praticipate:
http://xoops.org/modules/newbb/viewtopic.php?post_id=347875#forumpost347875