Comparing surface digitization techniques in palaeontology using visual perceptual metrics and distance computations between 3D meshes

Abstract

The use of surface digitization techniques andmethods in palaeontology has increased in the last twodecades, mainly due to recent improvements in devicesand software. However, many digitization efforts are pub-lished only as 3D models, with only a few details on theexact protocols used and sometimes not even indicatinghow to access these digital data, thus reducing the long-term reusability of the obtained files. It is important toinclude this information, as the applied techniques andworkflows have significant effects on the final quality of3D models. We compare 3D meshes created by seven dif-ferent surface digitization techniques and protocols for asauropod caudal vertebra and a testudine turtle in a flatslab of rock. These two specimens represent typicalexamples of objects in vertebrate palaeontology collections,making them a suitable sample for our tests. Besides thesequantitative and topological comparisons we also havecomputed visual perceptual metrics, which aim to predictthe visual quality of a 3D model as perceived by a humanobserver. Our results agree with previous works, confirm-ing that photogrammetry is one of the most suitableoptions for obtaining high quality 3D models of fossils,producing higher quality meshes than current structuredlight 3D scanners.