Many 3D scanning systems and software tools are currently available, but a comparative study of their actual precision and robustness still lacked. To this end we compared three alignment tools and two merging tools that were used during the reconstruction of a 3D model out of scanned data. The comparison was based on the scanning and reconstruction of two relatively complex artistic sculptures and a number of "ground truth" objects. The quality of the reconstructed 3D models is evaluated using both qualitative and quantitative measures. Quantitative evaluation was performed using Metro, a tool for computing differences between 3D meshes. We found that tools for the alignment and merging of range scans using similar heuristics may show a difference in accuracy, even in case of range scans without noise.

F. ter Haar, P. Cignoni, P. Min, and R.C. Veltkamp. A Comparison of Systems and Tools for 3D Scanning. In: Proceedings of 3D Digital Imaging and Modeling: Applications of Heritage, Industry, Medicine and Land" (17-18 May 2005, Padua, Italy).

Approach

·        A set of both physical objects and synthetic objects were used.

·        Physical objects were scanned using the Roland Picza LPX-250 laser range scanner.

·        The rough alignment of scans was performed by manually selecting four correspondence points between the overlapping pairs of meshes.

·        The fine alignment of scans was performed using the tools: MeshAlign (CNR/ISTI), Scanalyze (Stanford), and RapidForm (INUS techn.)

·        The aligned scans were compared with a High Fidelity reference model using metro.

·        The scans were merged using MeshMerge (CNR/ISTI) and RapidForm using both volumetric distance field, and surface zippering techniques.

·        The merged scans were compared with a High Fidelity reference model using metro.