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Viewpoint-Based Ambient Occlusion
March/April 2008 (vol. 28 no. 2)
pp. 44-51
Francisco González, University of Girona
Mateu Sbert, University of Girona
Miquel Feixas, University of Girona
Ambient occlusion is a powerful technique that mimics indirect global illumination at a fraction of the cost. In this paper, we introduce a new ambient occlusion technique based on an information-theoretic framework. We define a viewpoint quality measure using information accessible through a channel built between a set of viewpoints and an object's polygons. By inverting this channel, we can access polygon information from all viewpoints. From this polygonal information, we obtain an occlusion map that we can use as a classic ambient occlusion technique, as well as in several other applications. We can, for example, use the map to guide viewpoint selection by highlighting the most informative object views; to enhance object features, such as its most salient parts; and to produce nonphotorealistic object visualizations.

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Index Terms:
ambient occlusion, obscurances, information theory, viewpoint selection, nonphotorealistic rendering
Francisco González, Mateu Sbert, Miquel Feixas, "Viewpoint-Based Ambient Occlusion," IEEE Computer Graphics and Applications, vol. 28, no. 2, pp. 44-51, March-April 2008, doi:10.1109/MCG.2008.41
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