Assessing the accuracy of high-resolution topographic data generated using freely available packages based on SfM-MVS approach

The manual data collection for topographic details with high-resolution is almost impractical even for a small area. Recently, the SfM-MVS photogrammetry is extensively applied for the same. However, applications and associated challenges are not investigated so far for large physical models. Moreover, workflows using freely available packages have not been established yet for cost minimization. This study proposes two new workflows using a set of freely available packages for generating high-resolution DEM. A large outdoor river-network-floodplain setup is considered to investigate accuracy. The workflows are evaluated for two image sets, namely, CASE-I (considering only near parallel images) and CASE-II (considering convergent images in addition to CASE-I). The extensive accuracy tests show that the dome effect can be mitigated to a great extent using CASE-II dataset due to additional convergent images. The comparison with the PhotoScan confirms that the proposed workflows can be used for generating high-resolution DEM of large physical models.