The distortion correction algorithm applied on wide field of view space plane camera and the verification test

Abstract

In the laboratory verification test of space plane array camera with wide field of view, the image distortion caused by camera distortion will reduce the ranging accuracy for space camera with on orbit ranging function. In addition to verifying the performance of space camera, the distortion correction in laboratory stage can also verify the validity of distortion calibration results. First of all, a nonlinear distortion mathematical model including radial distortion and tangential distortion is established based on the principle of optical lens distortion. Distortion correction is generally divided into two steps. Firstly, the coordinate conversion relationship between each pixel in the ideal image and the corresponding pixel in the original image with distortion need to be established. The purpose of it is to make the pixel of original fall on the right position. Secondly, assign the gray value of the original image to the corresponding coordinate in the ideal image, and re-determine the gray value of the new pixel. By the bilinear interpolation method, the gray value of the original image with distortion is assigned to the undistorted image. Finally, the undistorted image can be obtained. The distortion correction algorithm is realized by MATLAB and verified on a space plane array camera. The corrected image distortion is less than 0.1 pixel