Basic feature of the physical system (please refer to illustration and pictures attached):
(1) Images are taken by an industrial line scan camera, and formed by scanning line by line.
(2) Illuminations are four LED bar lights with long diffuser (100x11100mm) in the front, they are far different from point light sources.
(3) The four bar lights are close to the object scanned. Two of them are only about 100 mm away from the scan line, and the other two are about 200 mm away.
(4) The four lights are turned on one after one, and four images are taken by line-scanning respectively. Size of each image can reach 1 GB, depending on the area scanned.
Basic development requirements:
(1) 1st independent function of specular and diffuse separation (dichromatic separation):
The four images scanned should be separate into specular component and diffuse component.
(2) 2nd independent function of calibrated photometric stereo (shape-from-shading):
Setup an workable calibrated photometric stereo system according to the physical system, use the diffuse component images from (1) for photometric stereo calculation to get albedo and depth map. Lens distortion correction should be part of the system developed.
(3) Time for (1) and (2) is expected to be within 10 minutes for typically 4 images of 1 GB of each.
Developers are expected to have solid experience with photometric stereo (shape-from-shading), and better also with dichromatic separation (specular removal). As to schedule, before June 30, 2019