“…The goal of camera calibration is to develop a mathematical model of the transformation between world points and observed image points resulting from the image formation process. The parameters which affect this mapping can be divided into three categories (Prescott & McLean, 1997, Zhuang & Roth, 1996: a) extrinsic (or external) parameters, which describe the relationship between the camera frame and the world frame, including position (3 parameters) and orientation (3 parameters); b) intrinsic (or internal) parameters, which describe the characteristics of the camera, and include the lens focal length, pixel scale factors, and location of the image center; c) distortion parameters, which describe the geometric nonlinearities of the camera. Some authors include distortion parameters in the group of intrinsic parameters (Tsai, 1987, Weng et al, 1992.…”