@article{ghosh_basis_2010,
	title = {A {Basis} {Illumination} {Approach} to {BRDF} {Measurement}},
	volume = {90},
	url = {http://ict.usc.edu/pubs/A%20Basis%20Illumination%20Approach%20to%20BRDF%20Measurement.pdf},
	doi = {10.1007/s11263-008-0151-7},
	abstract = {Realistic descriptions of surface reflectance have long been a topic of interest in both computer vision and computer graphics research. In this paper, we describe a novel high speed approach for the acquisition of bidirectional reflectance distribution functions (BRDFs). We develop a new theory for directly measuring BRDFs in a basis representation by projecting incident light as a sequence of basis functions from a spherical zone of directions. We derive an orthonormal basis over spherical zones that is ideally suited for this task. BRDF values outside the zonal directions are extrapolated by re-projecting the zonal measurements into a spherical harmonics basis, or by fitting analytical reflection models to the data. For specular materials, we experiment with alternative basis acquisition approaches such as compressive sensing with a random subset of the higher order orthonormal zonal basis functions, as well as measuring the response to basis defined by an analytical model as a way of optically fitting the BRDF to such a representation. We verify this approach with a compact optical setup that requires no moving parts and only a small number of image measurements. Using this approach, a BRDF can be measured in just a few minutes.},
	number = {2},
	journal = {International Journal on Computer Vision},
	author = {Ghosh, Abhijeet and Heidrich, Wolfgang and Achutha, Shruthi and O'Toole, Matthew},
	year = {2010},
	keywords = {Graphics},
	pages = {183--197}
}