1996 Reports

Reflectance and Texture of Real-World Surfaces

Dana, Kristin J.; Nayar, Shree K.; Ginneken, Bram van; Koenderink, Jan J.

In this work, we investigate the visual appearance of real-world surfaces and the dependence of appearance on scale,viewing direction and illumination direction. At fine scale, surface variations cause local intensity variation or image texture. The appearance of this texture depends on both illumination and viewing direction and can be characterized by the BTF (bidirectional texture function). At sufficiently coarse scale, local image texture is not resolvable and local image intensity is uniform. The dependence of this image intensity on illumination and viewing direction is described by the BRDF (bidirectional reflectance distribution function). We simultaneously measure the BTF and BRDF of over 60different rough surfaces, each observed with over 200 different combinations of viewing and illumination direction. The resulting BTF database is comprised of over 12,000 image textures. To enable convenient use of the BRDF measurements, we fit the measurements to two recent models and obtain a BRDF parameter database. These parameters can be used directly in image analysis and synthesis of a wide variety of surfaces. The BTF, BRDF, and BRDF parameter databases have important implications for computer vision and computer graphics and each is made publicly available.