CURET: A Database of Reflectances and Textures of 60 Real-World Surfaces Dana, Ginneken, Nayar, Koenderink UCSC CMPS 290b, Fall 2005 Presented by Steven Scher

Steven Scher, BRDF: Reflectance with 4 angles Object Surface Normal Incident Light (2 angles) Reflected Light (2 angles)

Steven Scher, BTF: Reflected Image (2D) with 4 angles Surface Normal Incident Light (2 angles) Reflected Image (2 angles) 2-D image

Steven Scher, Image Collection Details Fixed Light Robotic Hand Camera Moved a few times Each Vertex is a surface orientation

Steven Scher, Database of Measured BRDF & BTF BRDF BRDF –Bidirectional Reflectance Distribution Function –What happens when an object is seen from a certain angle, lit from a certain angle? –4-dimensional (brightness for every viewing angle & lighting angle) BTF BTF –Bidirectional Texture Function –Extension of BRDF for 2.5-dimensional surfaces Some materials can’t be modeled well as a pattern painted onto an object, but don’t require a full 3D description of every pixel Some materials can’t be modeled well as a pattern painted onto an object, but don’t require a full 3D description of every pixel –6-dimensional (a 2-D picture for every viewing angle & lighting angle)

Steven Scher, Useful for Graphics Graphics Graphics –Better Rendering of 2.5-dimensional surfaces E.g. ( ) E.g. ( ) –Model for Further databases e.g. Skin types ( ) e.g. Skin types ( ) Photos from CAVE/curet/ BRDF BTF

Steven Scher, Possibilities for Vision Test for models that parametize texture better than lambertian surface model Test for models that parametize texture better than lambertian surface model Skin-Specific model for facial recognition? Skin-Specific model for facial recognition? Improved Shape-From-Shading, somehow? Improved Shape-From-Shading, somehow?

Steven Scher, Links Project Website Project Website – Dana’s Research Page Dana’s Research Page – Ginneken’s Papers – hp?author=bram&max_per_page=200 hp?author=bram&max_per_page=200http:// hp?author=bram&max_per_page=200

Steven Scher, Faces Kristin Dana Bram Van Ginneken Shree K. Nayar Jan J. Koenderink