0504286 20240103221954.120190429235959.9 85064275364 10.1007/s41095-019-0134-3 17 s. P cav_un_epca*04861152096-043351 (2019)73-89Springer effect coatings bidirectional texture function (BTF) measurement appearance psychophysical experiment cav_un_auth*0101086 Rozpoznávání obrazu Department of Pattern Recognition RO RO Department of Pattern Recognition 60 Filip Jiří UTIA-B K Ústav teorie informace a automatizace AV ČR, v. v. i. cav_un_auth*0282273 Rozpoznávání obrazu Department of Pattern Recognition RO RO Department of Pattern Recognition 40 Vávra Radomír UTIA-B Ústav teorie informace a automatizace AV ČR, v. v. i. http://library.utia.cas.cz/separaty/2019/RO/filip-0504286.pdf https://link.springer.com/article/10.1007/s41095-019-0134-3 cav_un_auth*0347019 GA17-18407S GA ČR Paint manufacturers strive to introduce unique visual effects to coatings in order to visually communicate functional properties of products using value-added, customized design. However, these effects often feature complex angularly dependent spatially-varying behavior, thus representing a challenge in digital reproduction. In this paper we analyze several approaches to capturing spatially-varying appearance of effect coatings. We compare a baseline approach based on bidirectional texture function (BTF) with four variants of half-difference parameterization. Through a psychophysical study we identify minimal sampling along individual dimensions of this parametrization. We conclude that bivariate representations preserve visual fidelity of effect coatings, while in contrast to BTF, better characterizing near-specular behavior and significantly restricting number of captured images. cav_un_auth*0374732 Computational Visual Media 2019 20190424 Bath GB 20190426 SCOPUS BD 20000 20200 20201 2020 2 RVO:67985556 http://hdl.handle.net/11104/0295985 S A 2019 85064275364 SCOPUS PUBMED WOS cav_un_epca*0486115 Computational Visual Media 2096-0433 2096-0662 Roč. 5 č. 1 2019 73 89 Springer