Fast Summed-Area Table Generation and its Applications

We introduce a technique to rapidly generate summed-area tables using graphics hardware. Summed area tables, originally introduced by Crow, provide a way to filter arbitrarily large rectangular regions of an image in a constant amount of time. Our algorithm for generating summed-area tables, similar to a technique used in scientific computing called recursive doubling, allows the generation of a summed-area table in O(log n) time. We also describe a technique to mitigate the precision requirements of summed-area tables. The ability to calculate and use summed-area tables at interactive rates enables numerous interesting rendering effects. We present several possible applications. First, the use of summed-area tables allows real-time rendering of interactive, glossy environmental reflections. Second, we present glossy planar reflections with varying blurriness dependent on a reflected object's distance to the reflector. Third, we show a technique that uses a summed-area table to r...

• Type: Journal
• Year: 2005
• Where: CGF
• Authors: Justin Hensley, Thorsten Scheuermann, Greg Coombe, Montek Singh, Anselmo Lastra
• Keywords: CGF 2005, Glossy Environmental Reflections, Large Rectangular Regions, Summed-area Table