Global illumination provides important visual cues to an animation, however its computational expense limits its use in practice. In this paper, we present an easy to implement technique for accelerating the computation of indirect illumination for an animated sequence using stochastic ray tracing. We begin by computing a quick but noisy solution using a small number of sample rays at each sample location. The variation of these noisy solutions over time is then used to create a smooth basis. Finally, the noisy solutions are projected onto the smooth basis to produce the final solution. The resulting animation has greatly reduced spatial and temporal noise, and a computational cost roughly equivalent to the noisy, low sample computation.

Paper (PDF)

To appear in SIGGRAPH 2006

Available as Pixar Technical Memo #06-03