title: Convergent iterative closest-point algorithm to accomodate anisotropic and inhomogenous localization error.
abstract: Since its introduction in the early 1990s, the Iterative Closest Point (ICP) algorithm has become one of the most well-known methods for geometric alignment of 3D models. Given two roughly aligned shapes represented by two point sets, the algorithm iteratively establishes point correspondences given the current alignment of the data and computes a rigid transformation accordingly. From a statistical point of view, however, it implicitly assumes that the points are observed with isotropic Gaussian noise. In this paper, we show that this assumption may lead to errors and generalize the ICP such that it can account for anisotropic and inhomogenous localization errors. We 1) provide a formal description of the algorithm, 2) extend it to registration of partially overlapping surfaces, 3) prove its convergence, 4) derive the required covariance matrices for a set of selected applications, and 5) present means for optimizing the runtime. An evaluation on publicly available surface meshes as well as on a set of meshes extracted from medical imaging data shows a dramatic increase in accuracy compared to the original ICP, especially in the case of partial surface registration. As point-based surface registration is a central component in various applications, the potential impact of the proposed method is high.
authors.affiliation: Division of Medical and Biological Informatics, German Cancer Research Center, Heidelberg, Germany. l.maier-hein@dkfz-heidelberg.de
authors.forename: Lena
authors.initials: L
authors.lastname: Maier-Hein
authors.forename: Alfred M
authors.initials: AM
authors.lastname: Franz
authors.forename: Thiago R
authors.initials: TR
authors.lastname: dos Santos
authors.forename: Mirko
authors.initials: M
authors.lastname: Schmidt
authors.forename: Markus
authors.initials: M
authors.lastname: Fangerau
authors.forename: Hans-Peter
authors.initials: HP
authors.lastname: Meinzer
authors.forename: J Michael
authors.initials: JM
authors.lastname: Fitzpatrick
mesh_terms: D000465:Algorithms; D000818:Animals; D016880:Anisotropy; D003952:Diagnostic Imaging; D006257:Head / Q000033:anatomy & histology; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods*; D025341:Principal Component Analysis; D011817:Rabbits