title: A laparoscopy-based method for BRDF estimation from in vivo human liver.
abstract: While improved visual realism is known to enhance training effectiveness in virtual surgery simulators, the advances on realistic rendering for these simulators is slower than similar simulations for man-made scenes. One of the main reasons for this is that in vivo data is hard to gather and process. In this paper, we propose the analysis of videolaparoscopy data to compute the Bidirectional Reflectance Distribution Function (BRDF) of living organs as an input to physically based rendering algorithms. From the interplay between light and organic matter recorded in video images, we propose the definition of a process capable of establishing the BRDF for inside-the-body organic surfaces. We present a case study around the liver with patient-specific rendering under global illumination. Results show that despite the limited range of motion allowed within the body, the computed BRDF presents a high-coverage of the sampled regions and produces plausible renderings.
authors.affiliation: Institute of Informatics, Federal University of Rio Grande do Sul, Porto Alegre, Brazil; Federal Institute of Paraná, Londrina, Brazil. Electronic address: alpnunes@inf.ufrgs.br.
authors.forename: A L P
authors.initials: ALP
authors.lastname: Nunes
authors.affiliation: Institute of Informatics, Federal University of Rio Grande do Sul, Porto Alegre, Brazil.
authors.forename: A
authors.initials: A
authors.lastname: Maciel
authors.affiliation: Institute of Health Sciences, Federal University of Rio Grande do Sul, Porto Alegre, Brazil.
authors.forename: L T
authors.initials: LT
authors.lastname: Cavazzola
authors.affiliation: Institute of Informatics, Federal University of Rio Grande do Sul, Porto Alegre, Brazil.
authors.forename: M
authors.initials: M
authors.lastname: Walter
mesh_terms: D000465:Algorithms; D003196:Computer Graphics; D006801:Humans; D010535:Laparoscopy / Q000379:methods*; D008029:Lighting; D008099:Liver / Q000033:anatomy & histology*; D012680:Sensitivity and Specificity
keywords: In vivo organ simulation; Inverse rendering; Laparoscopy-based BRDF; Virtual surgery