No, it really only covers code… But no license means all rights stay with the owner amyway. To be secure in case of a court trial, you'd have to go to a… (Notar in german) and put a copy of the artwork there.
http://creativecommons.org/choose/
This license will allow users to re-use and re-distribute your artists' work, but they may not alter it, use it for commercial purposes, or without attributing the work to the author in whichever way was specified.
http://creativecommons.org/licenses/by-nc-nd/3.0/us/
http://creativecommons.org/choose/results-one?q_1=2&q_1=1&field_commercial=n&field_derivatives=n&field_jurisdiction=us&field_format=StillImage&field_worktitle=&field_attribute_to_name=&field_attribute_to_url=&field_sourceurl=&field_morepermissionsurl=&lang=en_US&language=en_US&n_questions=3
Superb. Thanks guys.