A Novel Multi-camera Calibration Method Using Transparent Glass Calibration Board

Traditional multi-camera calibration is usually on one side of the calibration board. If there are several cameras distributing on both sides of the calibration board, each camera needs to be calibrated on each side. Thus, the error accumulated from each calibration will have a non-ignorable impact on the results. In this paper, we presents a method that using transparent glass board to replace ordinary calibration board based on Zhang Zhengyou's calibration method. We also introduce two new parameters (depth and refractive index of glass). Therefore, calibration of several cameras can be completed by one experiment. The calibration of camera in the front of the transparent glass board uses traditional calibration method and LM iterative algorithm to obtain the internal and external camera parameters. The calibration of camera on back side uses the traditional calibration model and the light refraction model, and the results without considering the refraction condition are served as the initial values. Then the initial values are optimized by the nonlinear iteration method to obtain the precise camera parameters of the camera. Finally, the internal and external parameters of the whole multi-camera system are obtained. The calibration process is accurate and rapid. Thus, our method has highly practicability for multi-camera calibration with opposite distribution.