3D Reconstruction of rock paintings: a cost-effective approach based on modern photogrammetry for rapidly mapping archaeological findings

The work describes a cost-effective methodology for the creation of 3D virtual models with both metric and photo-realistic content developed for archaeologists who need to rapidly map new findings during their field prospections. The potential of modern photogrammetry approach, based on Structure from Motion (SfM) and dense image matching algorithms, coupled with the use of low-cost cameras is evaluated for the creation of 3D models and orthophotos of rock paintings. The case study is located in Brealito valley, in the Calchaqui basin of the Province of Salta, Argentina. In these wide areas, actually known for the naturalistic value, a huge amount of archeological remains was found and surveyed for the first time in August 2013 within a research project funded by the Italian Ministry of Foreign Affairs. A methodological approach to record the findings in a cost-effective and reliable way is defined, acquisitions are performed with common use instruments such as digital cameras (off-the-shelf and single lens reflex - SLR) and measuring tapes. The novelty of the work lies in defining, experiencing and transferring to operators a simple methodology for digitizing and mapping the archeological heritage in order to provide 2D orthophotos and 3D models. Such methodology allows anyone, archaeologists or unprofessional personnel, to be trained and easily perform a survey in order to document, survey and study the investigated site.