摘要
为提高摄像机的标定精度,必须研究高精度的特征点提取方法。针对三种比较典型的标定图样:棋盘格,二维正弦条纹和高斯点阵,分析比较了相应的提取特征点算法和用于摄像机内参数标定的精度,得出基于傅里叶相位分析法的二维正弦条纹的特征点提取精度最高。并针对傅里叶方法处理二维正弦条纹不能准确提取边缘特征点的缺陷,提出了使用相移法提取正交相位以代替傅里叶方法得出正交相位的新方法。这种方法可以消除傅里叶变换滤波对点阵边缘的模糊作用,扩大了二维正弦条纹在摄像机标定中的适用范围。摄像机外参数标定实验表明该方法在处理包含边缘点的点阵时,重投影误差保持在原有水平,证明了其有效性。
In order to improve the camera calibration accuracy, characteristic points extraction method with high accuracy is needed. Three typical calibration patterns including checkerboard pattern, crossed sine fringe pattern, and Gaussian point matrix pattern are chosen. Corresponding characteristic points extraction algorithms are analyzed and compared, adding the comparison of accuracy in camera intrinsic parameters calibration, the best one is crossed sine fringe pattern based on Fourier phase analysis. To avoid the drawback that the Fourier method used in the crossed sine fringe pattern cannot handle with characteristic points located in the edge of the point matrix, a novel method that using phase-shift method instead of Fourier method is proposed to obtain the crossed phase. The new method can eliminate the indistinct affect in the edge of the point matrix caused by Fourier translation filtering, so to amplify the scope of application of crossed sine fringe pattern in camera calibration. The extrinsic parameters calibration experiment show that the new method is effective in handling point matrix including edge points, for the reprojection error keeps in original level.
出处
《光学学报》
EI
CAS
CSCD
北大核心
2014年第5期171-178,共8页
Acta Optica Sinica
基金
国家自然科学基金(61205007)
四川省科技创新研究团队项目(2011JTD0001)
关键词
机器视觉
特征点提取
相位提取
二维正弦条纹
棋盘格
高斯点阵
machine vision
characteristic points extraction
phase extraction
crossed sine fringe pattern
checkerboard pattern
Gaussian point matrix pattern
作者简介
李璐璐(1988-),女,博士研究生,主要从事机器视觉与光学测量方面的研究。E—mail:white_lu@tom.com
导师:伍凡(1957-),男,研究员,博士生导师,主要从事先进光学制造和测试技术方面的研究。E-mail:wufan@ioe.ac.cn