Rendering of human skin during physical exercise

Abstract

Many researchers have shown interest in the realistic rendering of a human face since it is crucial to the success of many applications in computer graphics, games and animation. However, it is difficult to represent the realistic appearance of a facial skin since it has complex physical properties and its appearance tends to vary as the situation changes. For example, the glossiness of a facial skin increases after exercise and the color of it becomes red after drink. In this paper, we introduce a method to simulate the appearance change of a human skin during physical exercise. Our key idea is that the appearance of a skin under exercise can be divided into a surface reflectance component and a subsurface scattering component so that they are approximated by a BRDF model and a BSSRDF model, respectively. The Torrance-Sparrow BRDF model describes the glossiness and the roughness that are affected by sweat and oil on the skin surface. The Multipole model [Donner and Jensen 2005] with absorption σa and scattering σ's parameters represents subsurface scattering effects that occur between cells and pigments under the surface. In this paper, the parameters of each reflectance model are acquired by measurement.