Jinwei Gu Ravi Ramamoorthi Peter N. Belhumeur Shree K. Nayar Removing image artifacts due to dirty camera lenses and thin occluders. 2009 28 ACM Trans. Graph. 5 http://doi.acm.org/10.1145/1618452.1618490 db/journals/tog/tog28.html#GuRBN09