Inpainting for Fringe Projection Profilometry Based on Geometrically Guided Iterative Regularization

Abstract

Conventional fringe projection profilometry methods often have difficulty in reconstructing the 3D model of objects when the fringe images have the so-called highlight regions due to strong illumination from nearby light sources. Within a highlight region, the fringe pattern is often overwhelmed by the strong reflected light. Thus, the 3D information of the object, which is originally embedded in the fringe pattern, can no longer be retrieved. In this paper, a novel inpainting algorithm is proposed to restore the fringe images in the presence of highlights. The proposed method first detects the highlight regions based on a Gaussian mixture model. Then, a geometric sketch of the missing fringes is made and used as the initial guess of an iterative regularization procedure for regenerating the missing fringes. The simulation and experimental results show that the proposed algorithm can accurately reconstruct the 3D model of objects even when their fringe images have large highlight regions. It significantly outperforms the traditional approaches in both quantitative and qualitative evaluations.

Interpolating clothoid splines with curvature continuity

“…In Horn, it is defined a curve that minimises the square of the curvature, which is also called minimum energy curve; Baran et al proposes to minimise the total length of the clothoid spline. Examples of applications are shape editing as in Havemann et al, path tracking, path planning, traffic modelling, road geometry estimation, fringe projection, and manufacturing . A selection of functionals and BCs is herein proposed.…”

Dynamic projection theory for fringe projection profilometry

“…To deal with overexposure in the captured fringe pattern image, Ref. [26] estimates the geometric sketch of the error area first and uses iterative regularization to inpaint the fringe pattern. Only a fringe pattern is projected, so it is more efficient, but it is limited by the area size with error and is difficult to apply when the overexposed area is large.…”

Clothoid fitting and geometric Hermite subdivision

“…Concerning (ii), for a long time clothoids have been used by route designers as transitional curves between straight lines and circular arcs, and between circular arcs of different radii; see for instance [3,33]. Nowadays, they are further used in connection with path planning for autonomous vehicles, e.g., [2,5,10] in computer vision and image processing [8,27], in curve editing for design purposes [24], or representing hand-drawn strokes sketched by a user [9,32]. Concerning (i), many of the above applications are rather time critical and it is often important to have algorithms which are as fast as possible at a given (sometimes moderate) approximation quality.…”