Simple and Efficient Extrinsic Camera Calibration Based on A Rational Model

Calibration of the transformation between two planes, the image plane and the 2D platform, is important for applications where 2D metric information on the image plane is used to compute the 3D information in a world coordinate system. Efforts have been taken in computer vision literature to perform a full-scale camera calibration, including intrinsic and extrinsic parameters. For some applications, calibration of intrinsic parameters is not required as often as that of the extrinsic parameters. This paper addresses the problem of calibrating a camera's extrinsic parameters with respect to a 2D platform to which a camera is observing. A rational approximation method is proposed. Simulation and experimental results show that the proposed rational approximation method achieves comparable accuracy with the well-known homography-based approach. This work is motivated by our mobile sensor network project. Other relevant applications include vision-based metrology.