Depth of Field Postprocessing For Layered Scenes Using Constant-Time Rectangle Spreading Todd Jerome Kosloff Michael Tao Brian A. Barsky Electrical Engineering and Computer Sciences University of California at Berkeley Technical Report No. UCB/EECS-2008-187 http://www.eecs.berkeley.edu/Pubs/TechRpts/2008/EECS-2008-187.html December 30, 2008