Testing the value of low-cost Structure-from-Motion (SfM) photogrammetry for metric and visual analysis of rock art

The discussion of digital photogrammetry and/or 3D laser scanning for recording the geometry of rock art sites is not new, but the production of high-quality 3D models requires great expenditure and specialized personnel that are not accessible to everyone or applicable to all sites. While the use of low-cost cameras and photogrammetry has been suggested as an alternative for fast visualization of rock art, do the results have enough quality for the metric and visual analysis of the art? This paper explores the potential of low-cost Structure-from-Motion (SfM) photogrammetry performed by non-professional surveyors, with no camera calibration and no tripod to speed the process, as an alternative cost-effective tool for quantitative and qualitative analysis of rock art. The innovative aspect of this paper is that we have verified the metric accuracy and graphic quality of low-cost 3D models and shown that they can be used as an effective low-cost tool for detailed analysis and tracing of rock art.