Title :
Determining shape and reflectance properties objects by using diffuse illumination
Author :
Kim, Tae-Eun ; Ryu, S.H. ; Choi, J.S.
Author_Institution :
Dept. of Electron. Eng., Chung-Ang Univ., Seoul, South Korea
Abstract :
We propose a technique to estimate reflectance properties and the recovery of shape by using the Sample sphere and Diffuse Illumination Method. The Photometric Stereo Method (PSM) is generally based on a direct light source. Our PSM is modified with diffuse illumination and then applied to a hybrid reflectance model which consists of two main components, Lambertian and specular reflectance. A sample sphere made of one material is used to estimate the reflectance properties by using the LMS algorithm. We make a reference table which consists of surface normal and brightness values using estimated reflectance parameters. The photometric matching method proposed is robust because it matches object images with the reference table considering the neighbor brightness distribution. The 3-D shape of an object can be recovered from pixel intensity distribution and a reference table. The algorithm should be applicable to vision inspection systems
Keywords :
brightness; image matching; image reconstruction; image sampling; least mean squares methods; photometry; reflectometry; shape measurement; stereo image processing; 3-D shape; LMS algorithm; Lambertian reflectance; diffuse illumination; hybrid reflectance model; neighbor brightness distribution; object image matching; object reflectance properties; object shape determination; photometric stereo method; pixel intensity distribution; reference table; sample sphere method; shape recovery; specular reflectance; surface normal; vision inspection systems; Brightness; Least squares approximation; Light sources; Lighting; Machine vision; Parameter estimation; Photometry; Reflectivity; Robustness; Shape;
Conference_Titel :
Circuits and Systems, 1996., IEEE Asia Pacific Conference on
Conference_Location :
Seoul
Print_ISBN :
0-7803-3702-6
DOI :
10.1109/APCAS.1996.569328