"Estimating Specular Roughness from Polarized Second Order Spherical Gradient Illumination"
Abhijeet Ghosh, Tongbo Chen, Pieter Peers, Cyrus A. Wilson, and Paul Debevec

SIGGRAPH 2009: Talks, July 2009
Abstract
We present a novel method for estimating specular roughness and tangent vectors, per surface point, from polarized second order spherical gradient illumination patterns. We demonstrate that for isotropic BRDFs, only three second order spherical gradients are sufficient to robustly estimate spatially varying specular roughness. For anisotropic BRDFs, an additional two measurements yield specular roughness and tangent vectors per surface point. We verify our approach with different illumination configurations which project both discrete and continuous fields of gradient illumination. Our technique provides a direct estimate of the per-pixel specular roughness and thus does not require off-line numerical optimization that is typical for the measure-and-fit approach to classical BRDF modeling.


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Related Publications
  • Abhijeet Ghosh, Tongbo Chen, Pieter Peers, Cyrus A. Wilson, and Paul Debevec, "Estimating Specular Roughness and Anisotropy from Second Order Spherical Gradient Illumination", Computer Graphics Forum, Volume 28, Issue 4, pages 1161-1170, 2009,
Bibtex
@misc{Ghosh:2009:ESR:Talk,
author = {Ghosh, Abhijeet and Chen, Tongbo and Peers, Pieter and Wilson, Cyrus A. and Debevec, Paul},
title = {Estimating Specular Roughness from Polarized Second Order Spherical Gradient Illumination},
month = {July},
year = {2009},
howpublished = {SIGGRAPH 2009: Talks}
doi = {http://doi.acm.org/10.1145/1597990.1598020},
}
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