基于全局代价函数优化的立体标定方法  

Stereo calibration based on global cost function optimizion

作　　者：苑英海[1] 方勇纯[1] 张雪波[1] 

机构地区：[1]南开大学机器人与信息自动化研究所,天津300071

出　　处：《仪器仪表学报》2011年第10期2228-2234,共7页Chinese Journal of Scientific Instrument

基　　金：国家自然科学基金面上项目(60875055);天津市应用基础及前沿技术研究计划重点项目(08JCZDJC21800);高等学校博士学科点专项科研基金(20090031110035)资助项目

摘　　要：提出了一种基于全局代价函数的立体标定方法。以张正友的单目摄像机标定算法为基础,同时选择合适的径向畸变模型,将左右摄像机的内参数、摄像机与标定板之间的外参数、镜头畸变系数,以及两个摄像机之间的外参数标定相互融合,使用一种约束性更强的全局代价函数作为优化目标进行非线性优化,经过一次优化便可以得到立体视觉系统中的摄像机参数。与通常的立体标定方法相比,该方法在目标函数中引入了左右摄像机之间外参数保持不变这一约束条件,从而使得重投影残差更小、标定精度更高,并且整个算法具有更强的鲁棒性。对比实验结果证明,这种基于全局代价函数优化的标定方法具有精度高、标定结果稳定等优点。This paper proposes a stereo calibration approach using global cost function optimization.Based on Zhang＇s monocular camera calibration method and an appropriate radial distortion model,the proposed method can calibrate all the parameters of stereo cameras efficiently,including intrinsic and extrinsic parameters of each camera,distortion coefficients,as well as the extrinsic parameters between cameras,through fusing a practical constraint to the global cost function.Compared with conventional stereo calibration method,the proposed approach takes into account the fact that the extrinsic parameters between two cameras are invariant.Therefore,the designed calibration technique provides more robustness and more accurate results with a smaller reprojection error in practice.Comparison experiment results show the superior performance of the proposed approach in terms of good robustness and accuracy over that of con-ventional calibration methods.

关 键 词：立体标定 畸变模型 非线性优化 

分 类 号：TP391.41[自动化与计算机技术—计算机应用技术]