title: Interactive rendering of acquired materials on dynamic geometry using frequency analysis.
abstract: Shading acquired materials with high-frequency illumination is computationally expensive. Estimating the shading integral requires multiple samples of the incident illumination. The number of samples required may vary across the image, and the image itself may have high- and low-frequency variations, depending on a combination of several factors. Adaptively distributing computational budget across the pixels for shading is a challenging problem. In this paper, we depict complex materials such as acquired reflectances, interactively, without any precomputation based on geometry. In each frame, we first estimate the frequencies in the local light field arriving at each pixel, as well as the variance of the shading integrand. Our frequency analysis accounts for combinations of a variety of factors: the reflectance of the object projecting to the pixel, the nature of the illumination, the local geometry and the camera position relative to the geometry and lighting. We then exploit this frequency information (bandwidth and variance) to adaptively sample for reconstruction and integration. For example, fewer pixels per unit area are shaded for pixels projecting onto diffuse objects, and fewer samples are used for integrating illumination incident on specular objects.
authors.affiliation: University of Montréal, Dept. informatique et de recherche operationelle, Faculte des arts et des sciences, C.P. 6128, succ. Centre-Ville, Montréal, Québec H3C 3J7, Canada. m.m.bagher@gmail.com
authors.forename: Mahdi Mohammad
authors.initials: MM
authors.lastname: Bagher
authors.forename: Cyril
authors.initials: C
authors.lastname: Soler
authors.forename: Kartic
authors.initials: K
authors.lastname: Subr
authors.forename: Laurent
authors.initials: L
authors.lastname: Belcour
authors.forename: Nicolas
authors.initials: N
authors.lastname: Holzschuch
mesh_terms: D000465:Algorithms; D003196:Computer Graphics; D003627:Data Interpretation, Statistical; D007089:Image Enhancement / Q000379:methods*; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D021621:Imaging, Three-Dimensional / Q000379:methods*; D008029:Lighting / Q000379:methods*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D012815:Signal Processing, Computer-Assisted