Fisheye Camera Calibration with Two Pairs of Vanishing Points

A fisheye camera calibration method is proposed by using two pairs of vanishing points from one single fisheye view in this paper. Aiming at a plane scene including two groups of parallel straight lines with different direction, one single fisheye image is viewed by a fisheye camera. Four vanishing points can be first computed by the intersection of the image line in the fisheye image. Since line segment joining a pair of vanishing points with same direction passes through the image center, the principal point is estimated by joining two pairs of vanishing point. Second, the focal length and aspect ratio may be obtained by using this property of two vanishing points corresponding one group parallel straight line. Last, we choose the estimated basic intrinsic parameters as an initial value, the fisheye lens distortion parameters may further be refined by minimizing the objective function from all fisheye image points on the same great circle. Experimental results demonstrate the validity of our method.