Structure-from-Motion 3D Reconstruction of the Historical Overpass Ponte della Cerra: A Comparison between MicMac® Open Source Software and Metashape®

In recent years, the performance of free-and-open-source software (FOSS) for image processing has significantly increased. This trend, as well technological advancements in unmanned aerial vehicle (UAV) industry, have opened blue skies both researchers and surveyors. this study, we aimed to assess quality sparse point cloud obtained with a consumer UAV FOSS. To achieve goal, also process same dataset commercial package using its results term comparison. Various analyses were conducted, such residuals analysis, statistical analysis GCPs CPs errors, relative accuracy assessment, Cloud-to-Cloud distance A support survey was conducted measure 16 markers identified on object. particular, 12 these used ground control points scale 3D model, while remaining 4 check scaling procedure by examining residuals. Results indicate that clouds are comparable. MicMac® mean equal 0.770 pixels Metashape® is 0.735 pixels. addition, errors similar: error 0.037 m standard deviation 0.017 m, whereas Metashape®, it 0.031 0.015 m. The present work represents preliminary study: comparison between packages something hard achieve, given secrecy theoretical differences approaches. case study analyzes an object extremely complex geometry; placed urban canyon where GNSS can not be exploited. scenario changes continuously due vehicular traffic.