I edited a cc-by2.0 image to a degree that I believe creates a new work, which I license under CC-BY 3.0.
It tiles.
Attribution Instructions:
Sameba by Paata Vardanashvili <http://commons.wikimedia.org/wiki/File:Sameba_13.jpg> | Sandstone Ornament created by qubodup <http://qubodup.net> | hosted by <opengameart.org> | license: CCBY3.0 <http://creativecommons.org/licenses/by/3.0/>