The 12th International Conference on Scour and Erosion (ICSE 2025)

This study compares digital stereophotography and close-range photogrammetry for 3D bathymetry reconstruction using identical image data in a controlled dry test setup. Digital stereophotography employs two synchronized cameras with a base plate and markers for accurate positioning, achieving sub-millimeter accuracy through pose estimation and triangulation. However, simultaneous imaging requirements limit its adaptability. In contrast, Agisoft Metashape Professional Edition utilizes advanced Structure-from-Motion (SfM) algorithms to construct accurate 3D models, accommodating incomplete datasets and diverse image acquisition conditions with greater flexibility. The key distinctions between the aforementioned techniques include control point requiremecnts, the complexity of image processing, and the accuracy of generated Digital Elevation Models (DEMs). The study evaluates these methods based on accuracy, usability, and computational efficiency. The results show that while stereophotography is highly accurate, Agisoft Metashape offers even better accuracy and resolution. These findings establish a framework for selecting the most effective 3D reconstruction techniques for specialized laboratory environments.