Planned Sampling of Spatially Varying BRDFs

Measuring reflection properties of a 3D object involves capturing images for numerous viewing and lighting directions. We present a method to select advantageous measurement directions based on analyzing the estimation of the bi-directional reflectance distribution function (BRDF). The selected directions minimize the uncertainty in the estimated parameters of the BRDF. As a result, few measurements suffice to produce models that describe the reflectance behavior well. Moreover, the uncertainty measure can be computed fast on modern graphics cards by exploiting their capability to render into a floating-point frame buffer. This forms the basis of an acquisition planner capable of guiding experts and non-experts alike through the BRDF acquisition process. We demonstrate that spatially varying reflection properties can be captured more efficiently for real-world applications using our acquisition planner.