Spectrally optimal sampling for distribution ray tracing

Nonuniform sampling of images is a useful technique in computer graphics, because a properly designed pattern of samples can make aliasing take the form of high-frequency random noise. In this paper, the technique of nonuniform sampling is extended from two dimensions to include the extra parameter dimensions of distribution ray tracing. A condition for optimality is suggested, and algorithms for approximating optimal sampling are developed. The technique is demonstrated at low sampling densities, so the characteristics of aliasing noise are clearly visible. At supersampling rates, this technique should move noise into frequencies above the passband of the pixel-reconstruction filter. CR Categories and Subject Descriptions: I.3.3 [ Computer Graphics ]: Picture/Image Generation; I.3.7 [ Computer Graphics ]: Three-Dimensional Graphics and Realism General Terms: Algorithms Additional Keywords and Phrases: Antialiasing, Distribution Ray Tracing, Nonuniform Sampling, Noise Perception

• Type: Conference
• Year: 1991
• Where: SIGGRAPH
• Authors: Don P. Mitchell
• Keywords: Computer Graphics, Distribution Ray, Nonuniform Sampling, SIGGRAPH 1991