A Simple Calibration Procedure for Fish-Eye (High-Distortion) Lens Camera

This paper presents a new algorithm for the geometric camera calibration of a fish-eye lens (a high distortion lens) mounted on a CCD TV camera. The algorithm determines a mapping between points in the world coordinate system and their corresponding point locations in the image plane. The parameters to be calibrated are effective focal length, one-pixel width on the image plane, image distortion center, and distortion coeficients. A simple calibration pattern consisting of equally spaced dots is introduced as a reference for calibration. Some parameters to be calibrated are eliminated b y setting up the calibration pattern precisely and assuming negligible distortion at the image distortion center. Thus, the number of unknown parameters t o be calibrated is drastically reduced, enabling simple and useful calibration. The method employs a polynomial transformation between points in the world coordinate system and their corresponding image plane locations. The coeflcients of the polynomial are determined using the Lagrangian estimation. Furthermore, the effectiveness of the proposed calibration method is confirmed by experimentation.