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A Curved Ray Camera for Handling Occlusions through Continuous Multiperspective Visualization
November/December 2010 (vol. 16 no. 6)
pp. 1235-1242
Jian Cui, Purdue University
Paul Rosen, University of Utah
Voicu Popescu, Purdue University
Christoph Hoffmann, Purdue University
Most images used in visualization are computed with the planar pinhole camera. This classic camera model has important advantages such as simplicity, which enables efficient software and hardware implementations, and similarity to the human eye, which yields images familiar to the user. However, the planar pinhole camera has only a single viewpoint, which limits images to parts of the scene to which there is direct line of sight. In this paper we introduce the curved ray camera to address the single viewpoint limitation. Rays are C1-continuous curves that bend to circumvent occluders. Our camera is designed to provide a fast 3-D point projection operation, which enables interactive visualization. The camera supports both 3-D surface and volume datasets. The camera is a powerful tool that enables seamless integration of multiple perspectives for overcoming occlusions in visualization while minimizing distortions.

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Index Terms:
Alleviating occlusions, camera model, curved rays, multiperspective visualization, interactive visualization
Citation:
Jian Cui, Paul Rosen, Voicu Popescu, Christoph Hoffmann, "A Curved Ray Camera for Handling Occlusions through Continuous Multiperspective Visualization," IEEE Transactions on Visualization and Computer Graphics, vol. 16, no. 6, pp. 1235-1242, Nov.-Dec. 2010, doi:10.1109/TVCG.2010.127
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