Photometric stereo endoscopy

Photometric stereo endoscopy.

While color video endoscopy has enabled wide-field examination of the gastrointestinal tract, it often misses or incorrectly classifies lesions. Many of these missed lesions exhibit characteristic three-dimensional surface topographies. An endoscopic system that adds topographical measurements to conventional color imagery could therefore increase lesion detection and improve classification acc...

System for Clinical Photometric Stereo Endoscopy

Photometric stereo endoscopy is a technique that captures information about the high-spatial-frequency topography of the field of view simultaneously with a conventional color image. Here we describe a system that will enable photometric stereo endoscopy to be clinically evaluated in the large intestine of human patients. The clinical photometric stereo endoscopy system consists of a commercial...

Towards Outdoor Photometric Stereo

This paper presents a framework to perform outdoor photometric stereo by utilizing environment light. We present the main considerations in designing the framework and steps of the processing pipeline. Our framework extends existing algorithms to meet the robustness and variability necessary to operate out of a laboratory environment. We verify our environment light photometric stereo framework...

Advances in Photometric Stereo

Ring-Light Photometric Stereo

We propose a novel algorithm for uncalibrated photometric stereo. While most of previous methods rely on various assumptions on scene properties, we exploit constraints in lighting configurations. We first derive an ambiguous reconstruction by requiring lights to lie on a view centered cone. This reconstruction is upgraded to Euclidean by constraints derived from lights of equal intensity and m...