Recent Improvements in Photometric Stereo for Rock Art 3D Imaging R. Dess` ı Department of Electrical and Electronic Engineering, University of Cagliari Piazza d’Armi 1, 09123 Cagliari. C. Mannu Department of Electrical and Electronic Engineering, University of Cagliari Piazza d’Armi 1, 09123 Cagliari. G. Rodriguez Department of Mathematics and Computer Science, University of Cagliari viale Merello 92, 09123 Cagliari G. Tanda Department of Archaeological and Historical-Artistic Sciences, University of Cagliari Piazza Arsenale, 1, 09124 Cagliari. M. Vanzi Department of Electrical and Electronic Engineering, University of Cagliari Piazza d’Armi 1, 09123 Cagliari. Abstract Recent improvements in photometric stereo (PS) are shown to remove the major limitations of such a low-cost 3D recording technique. In particular, there are significant improvements in lighting constraints, processing time and presence of deformation in reconstructed surfaces, allowing for fast and accurate restoration of shape and color information. The shooting technique is sufficiently easy to make PS ideal for ancient rock art, which is generally encountered in uncomfortable sites, with a large number of figures to sur- vey, often placed in a narrow space. This paper focuses on the Sardinia Email addresses: richidessi@gmail.com (R. Dess` ı), ca.mannu@gmail.it (C. Mannu), rodriguez@unica.it (G. Rodriguez), gtanda@unica.it (G. Tanda), vanzi@diee.unica.it (M. Vanzi) Preprint submitted to Digital Applications in Archaeology and Cultural Heritage (DAACH)May 14, 2015