@inproceedings{ghosh_circularly_2010,
	title = {Circularly {Polarized} {Spherical} {Illumination} {Reflectometry}},
	url = {http://ict.usc.edu/pubs/Circularly%20Polarized%20Spherical%20Illumination%20Reflectometry.pdf},
	abstract = {We present a novel method for surface reflectometry from a few ob- servations of a scene under a single uniform spherical field of circu- larly polarized illumination. The method is based on a novel anal- ysis of the Stokes reflectance field of circularly polarized spherical illumination and yields per-pixel estimates of diffuse albedo, spec- ular albedo, index of refraction, and specular roughness of isotropic BRDFs. To infer these reflectance parameters, we measure the Stokes parameters of the reflected light at each pixel by taking four photographs of the scene, consisting of three photographs with dif- ferently oriented linear polarizers in front of the camera, and one additional photograph with a circular polarizer. The method only assumes knowledge of surface orientation, for which we make a few additional photometric measurements. We verify our method with three different lighting setups, ranging from specialized to off-the- shelf hardware, which project either discrete or continuous fields of spherical illumination. Our technique offers several benefits: it estimates a more detailed model of per-pixel surface reflectance pa- rameters than previous work, it requires a relatively small number of measurements, it is applicable to a wide range of material types, and it is completely viewpoint independent.},
	booktitle = {{SIGGRAPH} {Asia}},
	author = {Ghosh, Abhijeet and Chen, Tongbo and Peers, Pieter and Wilson, Cyrus A. and Debevec, Paul},
	month = dec,
	year = {2010},
	keywords = {Graphics}
}