On cross-validation and resampling of BRDF data measurements

Vlastimil Havran, Attila Neumann, Georg Zotti, Werner Purgathofer, Hans-Peter Seidel
2005 Proceedings of the 21st spring conference on Computer graphics - SCCG '05  
ceiling floortile pinkwall walkway painted agglomerate granite polished ceramic plastic with a glossy varnish Figure 1: Four material samples as the subject of the validation. The samples are referred by their location in a building. Abstract We discuss the validation of BTF data measurements by means used for BRDF measurements. First, we show how to apply the Helmholtz reciprocity and isotropy for a single data set. Second, we discuss a cross-validation for BRDF measurement data obtained from
more » ... wo different measurement setups, where the measurements are not calibrated or the level of accuracy is not known. We show the practical problems encountered and the solutions we have used to validate physical setup for four material samples. We describe a novel coordinate system suitable for resampling the BRDF data from one data set to another data set. Further, we show how the perceptually uniform color space CIE 1976 L * a * b * is used for crosscomparison of BRDF data measurements, which were not calibrated.
doi:10.1145/1090122.1090149 dblp:conf/sccg/HavranNZPS05 fatcat:pai6qeh5nnfwhgnbdopds2voca