Videogrammetry vs Photogrammetry for heritage 3D reconstruction

In the last years we are witnessing an increasing quality (and quantity) of video streams and a growing capability of SLAM-based methods to derive 3D data from videos. Video sequences can be easily acquired by non-expert surveyors and possibly used for 3D documentation purposes. The aim of the paper is to evaluate the possibility to perform 3D reconstructions of heritage scenarios using videos (“videogrammetry”), e.g. acquired with smartphones. Video frames are extracted from the sequence using a fixed-time interval and two advanced methods. Frames are then processed applying automated image orientation / SfM and dense image matching / Multi-View Stereo (MVS) methods. Obtained 3D dense point clouds are then visually validated as well as compared with photogrammetric ground truth achieved acquiring images with a reflex camera or analysing 3D data’s noise on flat surfaces