Title
Optimised Path Space Regularisation
Abstract
We present Optimised Path Space Regularisation (OPSR), a novel regularisation technique for forward path tracing algorithms. Our regularisation controls the amount of roughness added to materials depending on the type of sampled paths and trades a small error in the estimator for a drastic reduction of variance in difficult paths, including indirectly visible caustics. We formulate the problem as a joint bias-variance minimisation problem and use differentiable rendering to optimise our model. The learnt parameters generalise to a large variety of scenes irrespective of their geometric complexity. The regularisation added to the underlying light transport algorithm naturally allows us to handle the problem of near-specular and glossy path chains robustly. Our method consistently improves the convergence of path tracing estimators, including state-of-the-art path guiding techniques where it enables finding otherwise hard-to-sample paths and thus, in turn, can significantly speed up the learning of guiding distributions.
Year
DOI
Venue
2021
10.1111/cgf.14347
COMPUTER GRAPHICS FORUM
DocType
Volume
Issue
Conference
40
4
ISSN
Citations 
PageRank 
0167-7055
0
0.34
References 
Authors
0
5
Name
Order
Citations
PageRank
Philippe Weier100.34
Marc Droske219412.12
Johannes Hanika329725.09
Andrea Weidlich49611.48
Jirí Vorba500.34