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its accomplishment. The basic methods of camera calibration can be divided into two categories:
traditional camera calibration methods, such as direct linear transformation method (DLT
method), R. Tsai’ RAC method, Zhang Zhengyou’ plane calibration, Meng Xiaoqiao and Hu
Zhanyi’ round calibration method, Wu Yihong’ parallel circular calibration method , as well as
the camera self-calibration methods, such as self-calibration based on Kruppa equations method,
stratified gradually calibration, self-calibration based on quadric method, etc. Hardly,some
ways are not involved in these two types of methods, such as active vision camera calibration
method. In the paper, based on the geometric model of camera imaging, the design of these
methods is analyzed, the process of camera calibration is completed, and the advantages and
disadvantages of several methods with their used field are presented. The camera calibration is
provided reference in the practical application, and a more reasonable calibration method which
will be further chosen is provided theoretical and practical reference.
Keywords: camera calibration; intrinsic parameter; external parameters; distortion; corner
detection
前言
计算机视觉的基本任务之一是从摄像机获取的图像信息出发计算三维空间中物体的
几何信息。而空间物体表面某点的三维几何位置与其在图像中对应点之间的相互关系是由
摄像机成像的几何模型决定的。摄像机标定是机器视觉技术
[1]
的基础, 应用于三维测量、
三维物体重建、机器导航、视觉监控、物体识别、工业检测、生物医学、机器人手眼等诸
多领域, 得到了国内外学者的广泛研究
[2]
。它是光学非接触式三维测量的首要步骤,是二
维图像获取三维空间信息的关键和必要步骤。无论是在图像测量或者机器视觉应用中,摄
像机参数的标定都是非常关键的环节,其标定结果的精度及算法的稳定性直接影响摄像机
工作产生结果的准确性如基于图像的物体重构、基于图像的测量等。对摄像机标定的研究
来说,当前的研究工作应该集中在如何针对具体的实际应用问题,采用特定的简便、实用、
快速、准确的标定方法
[3]
。
摄像机标定的分类根据是否需要标定参照物来看,可分为传统的摄像机标定方法和摄
像机自标定方法
[4]
。传统的摄像机标定是在一定的摄像机模型下,基于特定的实验条件,
如形状、尺寸已知的标定物,经过对其进行图像处理,利用一系列数学变换和计算方法,