Shape and Reflectance from Scattering in Participating Media

Most shape and reflectance acquisition methods use the light reflected from objects´ surfaces. When the reflection cannot be observed, e.g., when the object´s surface is black matte or highly specular, its shape and reflectance are difficult to acquire. In this paper, we propose a method that can measure shape and reflectance with another approach. Our method involves the use of the scattering of reflected light in a participating media instead of using only the light reflection. We place the target in a participating medium and focus a laser beam on it. Cameras can observe the scattering of reflected light toward all reflection angles even if they can only observe light reflected toward the cameras. Experimental results showed that our method can acquire the shape and reflectance of various surfaces.