How to create a unique image file name containing umlauts or accents on upload?

The Problem:
Image file names that contain umlauts, accents or empty spaces do not display properly on the server once they are uploaded.
examples: märz.jpg, hôtel.jpg or march photo.jpg, hôtel à paris.jpg

Needed Solution:
I would like to be able to rename the uploaded image file with a unique file name that also gets inserted into the DB.
Example "märz.jpg" or "march photo.jpg" would be renamed to something like: "18732947.jpg" which also be inserted into the DB

On page 2 of the Digital File Pro Upload Wizard instructions it states:

Note: You may want to rename the file using a different naming convention by either: specifying a name directly, using the browse function, retrieving a name using available data bindings, or specifying server-side code to develop a dynamic naming convention.

Is this possible using any of the options above and, if so are there any examples / tutorials on how to do this?

Thanks