Date Awarded
Summer 2021
Document Type
Dissertation
Degree Name
Doctor of Philosophy (Ph.D.)
Department
Computer Science
Advisor
Pieter Peers
Committee Member
Weizhen Mao
Committee Member
Denys Poshyvanyk
Committee Member
Andreas Stathopoulos
Committee Member
Rance Necaise
Abstract
Bidirectional Reflectance Distribution Functions, (BRDFs), describe how light is reflected off of a material. BRDFs are captured so that the materials can be re-lit under new while maintaining accuracy. BRDF models can approximate the reflectance of a material, but are unable to accurately represent the full BRDF of the material. Acquisition setups for BRDFs trade accuracy for speed with the most accurate methods, gonioreflectometers, being the slowest. Image-based BRDF acquisition approaches range from using complicated controlled lighting setups to uncontrolled known lighting to assuming the lighting is unknown. We propose a data-driven method for recovering BRDFs under known, but uncontrolled lighting. This approach utilizes a dataset of 100 measured BRDFs to accurately reconstruct the BRDF from a single photograph. We model the BRDFs as Gaussian Mixture Models, (GMMs), and use an Expectation Maximization, (EM), approach to determine cluster membership. We apply this approach to captured data as well as synthetic. We continue this work by relaxing assumptions about either lighting, material, or geometry. This work was supported in part by NSF grant IIS-1350323 and gifts from Google, Activision, and Nvidia.
DOI
http://dx.doi.org/10.21220/s2-fwpk-zr81
Rights
© The Author
Recommended Citation
Cooper, Victoria, "Data-Driven Reflectance Estimation Under Natural Lighting" (2021). Dissertations, Theses, and Masters Projects. William & Mary. Paper 1627047864.
http://dx.doi.org/10.21220/s2-fwpk-zr81