High-dynamic-range camera-based bidirectional reflectance distribution function measurement system for isotropic materials

Abstract

We present a novel high-dynamic-range (HDR) camera-based bidirectional reflectance distribution function (BRDF) measurement system that can measure the reflectance property of isotropic materials. Our developed system can measure the BRDF of highly specular materials much faster than previous systems. It measures highly dense BRDF samples for a wider reflection angle with less noise so that it provides accuracy that is necessary for computer graphics application. To estimate the reflectance of a given material, we perform an absolute photometric calibration for the HDR camera. Our system is verified by checking the Helmholtz reciprocity and comparing the performance with that of previous image-based systems. The capability and efficiency of the developed system is demonstrated by comparing the images generated by measure-and-fit and direct-rendering methods using the measured data of four different isotropic materials.