EUROGRAPHICS 2015/ B. Bickel and T. Ritschel Short Paper Fractured Object Reassembly via Robust Surface Registration P. Mavridis, A. Andreadis and G. Papaioannou Athens University of Economics and Business Figure 1: Automatic reassembly of fractured cultural heritage objects from their parts using the proposed pipeline. Abstract The reassembly of fractured 3D objects from their parts is an important problem in cultural heritage and other domains. We approach reassembly from a geometric matching perspective and propose a pipeline for the automatic solution of the problem, where an efficient and generic three-level coarse-to-fine search strategy is used for the underlying global optimization. Key to the efficiency of our approach is the use of a discretized approximation of the surfaces’ distance field, which significantly reduces the cost of distance queries and allows our method to systematically search the global parameter space with minimal cost. The resulting reassembly pipeline provides highly reliable alignment, as demonstrated through the reassembly of fractured objects from their fragments and the reconstruction of 3D objects from partial scans, showcasing the wide applicability of our methodology. Categories and Subject Descriptors (according to ACM CCS): I.3.5 [Computer Graphics]: Computational Geometry and Object Modeling—Geometric algorithms, languages, and systems 1. Introduction and Related Work The problem of fractured object reassembly can be ap- proached from a surface matching perspective. Under the assumption that two matching fragments share a common contact surface, finding the optimal aligning transformation of the fragments is equivalent to finding the optimal align- ment of the corresponding contact surfaces. A recent survey on surface alignment methods can be found in Tam et al. [TCL * 13]. However, in the context of Cultural Heritage, this problem poses significantly more challenges than common geometric alignment, since phys- ical erosion of the contact surfaces, along with small miss- ing parts, create a large number of outliers. For this reason, specialized approaches have been proposed. A first solution for the reassembly of general 3D solids was proposed by Papaioannou et al. [PKT01], however the method assumes that fracture facets are nearly planar and match each other to a wide extent. Huang et al. [HFG * 06] proposed a feature- based alignment method that properly handles these cases and provides remarkable results, but the proposed system is rather complicated, consisting of several specialized algo- rithms for segmentation, multi-scale feature extraction, cor- respondence determination, registration, collision detection and supervised learning, something that makes the imple- mentation and adoption of the system difficult. Winkelbach et al. [WW08] also proposed a reassembly method based on c  The Eurographics Association 2015.