Reevaluating the Underlying Radial Symmetry Assumption of Camera Distortion

In camera distortion correction and calibration research, there is a prevalent assumption that distortion exhibits radial symmetry around a center of distortion (COD). However, the validity of this assumption is contingent upon the extent of tangential distortion in the system. This study delves into a quantitative analysis of tangential distortion by simulating diverse camera specifications and tilt angles between lenses and sensor arrays. The findings indicate that larger field-of-view and smaller pixel sizes lead to an augmentation of tangential distortion. In practical camera settings, the tangential distortion can extend beyond a dozen pixels. Consequently, traditional models relying on radial symmetry may encounter a decline in precision when addressing such distortions. Moreover, the study suggests that centers of distortion determined geometrically based on radial symmetry may not be numerically optimal in scenarios with tangential distortions. As a result, the robustness of the radial symmetry assumption may be compromised in the face of prominent trends in camera advancements.