Virtual camera calibration and stereo correspondence of single-lens bi-prism stereovision system using geometrical approach

•Stereo correspondence problem of single-lens biprism based stereovision system.•The virtual camera parameters are recovered based on a geometrical ray sketching.•Constructing virtual epipolar line using geometrical approach.•Results are compared to conventional calibration approach.

This paper proposes a simple geometrical ray approach to calibrate the extrinsic parameters of the virtual cameras and solve the stereo correspondence problem of the single-lens bi-prism stereovision system. Each images captured using this system can be divided into two sub-images which are generated by two virtual cameras due to the refraction through the bi-prism. This stereovision system is equivalent to the conventional two camera system and the two captured sub-images provide disparity which can be used for depth recovery. The virtual cameras will be calibrated geometrically and the correspondence problem of this system will be solved by applying epipolar geometry constraint on the generated virtual cameras instead of the real CCD camera. Experiments are conducted to validate the proposed method and the results are compared to the conventional approach to confirm its accuracy and effectiveness.