Flexible Calibration Method with High Accuracy for Dynamic Focusing
ZHOU Jiali1, JIA Lushuai1, WU Min2
1.College of Science, Zhejiang University of Technology, Hangzhou 310023 2.School of Science, Zhejiang University of Science and Technology, Hangzhou 310023
Abstract：The camera intrinsic parameters keep changing during the dynamic focusing process and different focusing states. By linking an angle sensor on the focusing ring, a camera model using the increment of the principal distance as the parameter is proposed based on the dynamic focusing process. The camera intrinsic parameters under arbitrary focusing state and object distance can be solved. A highly robust method is put forward by the customized stereo calibration target with three planes. Compared with the traditional model, no additional constraint condition is required and the proposed model has a strong operability. Experiments show the stronger image rectification ability of the proposed model and the corresponding calibration method. Furthermore, the precision of photogrammetry is improved by the proposed method.
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2016, Vol. 29 
