Integrated multi-scalar approach for 3D Cultural Heritage acquisitions

This contribution presents the results of investigations on the reliability of technologies based on the Structure from Motion approach for the 3D digitization of build heritage. Since in the architectonical survey field the level of detail of acquisitions is based on scales of representation that range between values that are generally compatible with the definition provided by some of the most widespread SfM technologies, we tested their performances and developed a procedure with the purpose of easing the work of surveyors called to restore digital representations at different scales. Restored 3D models were compared among each other and with a gold standard acquisition. These analysis led to qualitative and quantitative evaluations and to considerations on times and skills required by all tested technologies. Strengths and weaknesses are here highlighted and the integration of different technologies is presented, as it generally represents the best solution in most multi-scalar contexts.