Point Cloud accuracy of Smartphone Images: Applications in Cultural Heritage Environment

The 3D reconstruction of objects or structures belong to Cultural Heritage is a central theme in the field of conservation and restoration. In this context, photogrammetry with low-cost sensors represents an opportunity to survey in an easy, simple, accurate and economic way the immense Cultural Heritage. The aim of this research is to evaluate the achievable level of accuracy of the point cloud obtained from images generated by smartphones and processed in the Structure From Motion (SfM) and Multi View Stereo (MVS) environment. To validate the method of analysis, three case studies of structures belonging to the Cultural Heritage and present in southern Italy are shown in the paper. In particular, a comparison between the point clouds obtained by the smartphones and the point cloud obtained by digital reflex cameras and Terrestrial Laser Scanner was carried out. The results show a difference between the point clouds in the order of a few millimeters and, of consequence, the enormous potential of the smartphones in photogrammetry field.