The Impact of Photo Overlap, the Number of Control Points and the Method of Camera Calibration on the Accuracy of 3D Model Reconstruction

Abstract

This research attempted to determine the optimal photo overlap, number of control points and method of camera calibration for a photogrammetric 3D model reconstruction of an object of cultural heritage value. Terrestrial images of the object were taken with a hand‑held digital camera and processed in the ContextCapture software using the Structure‑from‑Motion (SfM) algorithm. A total station was used to measure ground control points (GCPs) and check points. Here, the research workflow, methodology, and various analyses concerning different configurations of the aforementioned factors are described. An attempt to assess the parameters which should be implemented in order to provide a high degree of accuracy of the model and reduce time‑consumption both during fieldwork and data processing was taken. The manuscript discusses the results of the analyses and compares them with other studies presented by different authors and indicates further potential directions of studies within this scope. Based on the authors’ experience with this research, some general conclusions and remarks concerning the planning of photo acquisition from the terrestrial level for the purpose of 3D model reconstruction were formulated.

Accuracy assessment of post‐processing kinematic georeferencing based on uncrewed aerial vehicle‐based structures from motion multi‐view stereo photogrammetry

“…In forested areas with sloping and undulating terrain, such as the one in this study, the distance between the UAV camera and the ground varies greatly, which prevents an adequate overlap rate at lower altitudes. High overlap ratios are important to obtain accurate DSMs (Dandois et al, 2015; Róg & Rzonca, 2021). Therefore, it is necessary to maintain a high flight altitude when performing photogrammetric surveys in forested areas with steep terrain.…”

Accuracy Assessment of Post-processing Kinematic Georeferencing Based on Real-time Kinematic Unmanned Aerial Vehicle and Structure-from-motion Photogrammetry: Topographic Measurements of a Riverbed in a Small Watershed with a Check Dam

“…At a flight altitude of 150 m, the horizontal and vertical errors were significantly more acceptable (within acceptable limits) than those at a flight altitude of 70 m (Table I and II). Results from the UAV-SfM method suggest a high overlap rate (> 80 %) is required to obtain an accurate DSM [27], [28]. In this study, the overlap ratio was set to 80 % for both the 70 m and 150 m flight altitudes.…”

Optimal UAV Image Overlap for Photogrammetric 3D Reconstruction of Bridges

“…However, this study mainly focused on the differences between orthographic photogrammetry and oblique photogrammetry and did not provide an optimal overlap suggestion. Róg and Rzonca [13] carried out a field test on a monument base and selected two adjacent walls to investigate the impact of different overlap configurations on the accuracy of 3D reconstruction. Four different photosets with the overlap of 90%, 80%, 70%, and 60% were collected by a hand-held digital camera and then processed to reconstruct 3D models.…”

“…The GSD was set to 1.5 mm/pixel, corresponding to a working distance of about 5.5 m. Regarding the overlap configuration of experimental cases, most studies on the optimal overlap used a set of consistent overlaps to investigate their impacts. For example, Róg and Rzonca [13] used four different photosets with overlaps of 90%, 80%, 70%, and 60% to reconstruct the walls of a monument base. Seifert, Seifert, Vogt, Drew, van Aardt, Kunneke and Seifert [11] investigate the effect of the forward overlap ranging from 91.9% to 98.8% on the performance of forest reconstruction.…”