@article{https://doi.org/10.1111/cgf.14139,
author = {Nabata, K. and Iwasaki, K. and Dobashi, Y.},
title = {Two-stage Resampling for Bidirectional Path Tracing with Multiple Light Sub-paths},
journal = {Computer Graphics Forum},
volume = {39},
number = {7},
pages = {219-230},
keywords = {CCS Concepts, • Computing methodologies → Computer graphics, Ray tracing},
doi = {https://doi.org/10.1111/cgf.14139},
url = {https://onlinelibrary.wiley.com/doi/abs/10.1111/cgf.14139},
eprint = {https://onlinelibrary.wiley.com/doi/pdf/10.1111/cgf.14139},
abstract = {Abstract Recent advances in bidirectional path tracing (BPT) reveal that the use of multiple light sub-paths and the resampling of a small number of these can improve the efficiency of BPT. By increasing the number of pre-sampled light sub-paths, the possibility of generating light paths that provide large contributions can be better explored and this can alleviate the correlation of light paths due to the reuse of pre-sampled light sub-paths by all eye sub-paths. The increased number of pre-sampled light subpaths, however, also incurs a high computational cost. In this paper, we propose a two-stage resampling method for BPT to efficiently handle a large number of pre-sampled light sub-paths. We also derive a weighting function that can treat the changes in path probability due to the two-stage resampling. Our method can handle a two orders of magnitude larger number of presampled light sub-paths than previous methods in equal-time rendering, resulting in stable and better noise reduction than state-of-the-art methods.},
year = {2020}
}