Coplanar light sweep-surface supported uncalibrated photometric stereo

In lambertian uncalibrated photometric stereo (VPS), the object surface albedo and normals, the lighting directions and intensities are determined up to an arbitrary invertible matrix. In this paper, a novel method is proposed to reduce such an ambiguity. With the support of a coplanar light sweep-surface (CLSS), some key normals are determined relative to a fiducial normal which is estimated by the CLSS. Thus the arbitrary transformation is reduced to invertible matrix up to a rotation and a scale. The rotation can be solved by controlling the direction of camera, the resulting ambiguity transformation can be finally determined up to a global scale.