Nonlinear camera calibration method of binocular stereo vision system
双目立体视觉系统的非线性摄像机标定技术*

Under the requirements of industrial inspection accuracy and real time application, this paper brought forward an improved two-step camera calibration method for binocular stereo vision systems based on the binocular imaging geometry model of the area-scan CCD camera with the using of LENZ distortion model, analyzed of the parameters and the limitations of the pinhole model. Using HALCON planar calibration board which were circular targets of two-way array and functions library, obtained the calibration marks and determined the marks and their projections with the sub-pixel precise edge contour detection algorithm and fitting ellipse method. The camera parameters were nonlinear optimized during this process. The accuracy of these parameters and stability of the algorithm were validated through experiments and accuracy analysis. The calibration me-thod is flexible and good portability.