Research on the calibration method of a biomimetic polarized imaging system based on a camera projection model

This paper establishes a mathematical model linking sky polarization information with the pinhole projection model and the equidistant projection model, tailored to the fisheye lens structure unique to polarized imaging systems. A quantitative analysis was carried out on the camera calibration and its camera parameters based on the two projection models. A method for calculating the height of the real image based on the distortion coefficients and the field of view angle was proposed. A bilinear interpolation sky polarization field image distortion correction algorithm based on the distortion coefficients of the two projection models was proposed, and indoor and outdoor calibration experiments were carried out. The experimental results show that the accuracy of the azimuth angle after indoor distortion correction can reach 0.479°, and the accuracy after outdoor distortion correction can reach 1.601°.