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Full-Text Articles in Physical Sciences and Mathematics
Data Driven Investigation Into The Off-Axis Brdf To Develop An Algorithm To Classify Anisotropicity, Anne W. Werkley
Data Driven Investigation Into The Off-Axis Brdf To Develop An Algorithm To Classify Anisotropicity, Anne W. Werkley
Theses and Dissertations
The Bi-directional Reflectance Distribution Function (BRDF) is used to describe reflectances of materials by calculating the ratio of the reflected radiance to the incident irradiance. While it was found that isotropic BRDF microfacet models maintained symmetry about ɸs = π, such symmetry was not maintained about the θs = θi axis, except for close to the specular peak. This led to development of a novel data-driven metric for how isotropic a BRDF measurement is. Research efforts centered around developing an algorithm that could determine material anisotropy without having to fit to models. The algorithm developed here successfully …
Comparison Of The Accuracy Of Rayleigh-Rice Polarization Factors To Improve Microfacet Brdf Models, Rachel L. Wolfgang
Comparison Of The Accuracy Of Rayleigh-Rice Polarization Factors To Improve Microfacet Brdf Models, Rachel L. Wolfgang
Theses and Dissertations
Microfacet BRDF models assume that a surface has many small microfacets making up the roughness of the surface. Despite their computational simplicity in applications in remote sensing and scene generation, microfacet models lack the physical accuracy of wave optics models. In a previous work, Butler proposed to replace the Fresnel reflectance term of microfacet models with the Rayleigh-Rice polarization factor, Q, to create a more accurate model. This work examines the novel model that combines microfacet and wave optics terms for its accuracy in the pp and ss polarized cases individually. The model is fitted to the polarized data in …