Analysis of wood surface waviness with a two-image photometric stereo method

Combination method: Photometric stereo with Shadows

This paper presents an algorithm allowing to perform photometric stereo with high accuracy results in the presence of shadows. First, we choose a combination of three images suited to reveal the presence of shadow and use it to calculate the normal vector on each pixel. This normal vector is then used to recalculate the intensity in order to evaluate the distance with the real intensities and d...

Average Surface Roughness Measurement Using Photometric Stereo Method

This paper presents a technique for measuring surface roughness (Ra), using photometric stereo method. The method utilizes three or more images of the measured surface from the same view point, taken sequentially under different illumination conditions. The scenes captured by the camera were reconstructed by the least square method to obtain surface normal from surface topography. Three-dimensi...

Photometric Stereo Reconstruction for Surface Analysis of Mucosal Tissue

We introduce photometric stereo reconstruction for surface analysis of mucosal tissue. Photometric stereo captures images of a surface from a single camera, but illuminated from different light sources. From the set of images, a detailed surface reconstruction is estimated. We apply photometric stereo principles to mucosal tissue, which raises technical challenges due to its specular appearance...

Albedo Recovery Using a Photometric Stereo Method

This paper describes a method for the calculation of surface reflectance values via photometric stereo. Experimental results show that surfaces rendered with reflectance values calculated by the proposed method have more realistic appearances than those with constant albedo. 1 Center for Image Technology and Robotics Tamaki Campus, The University of Auckland, Auckland, New Zealand. 2 Agilent Te...

An Application of the Photometric Stereo Method