视频测量椭圆标志中心点的高精度定位方法  

A high-precisioncentral point locating method for elliptical target in close-range video grammetry

作　　者：陈绍杰[1] 郑守住 赵文明 郭成成 金鑫[1] CHEN Shaojie;ZHENG Shouzhu;ZHAO Wenming;GUO Chengcheng;JIN Xin(School of Resource Engineering,Longyan University,Longyan,Fujian 364012,China;College of Surveying and Geo-Informatics,Tongji University,Shanghai 200092,China;School of Geographic Information and Tourism,Chuzhou University,Chuzhou,Anhui 239000,China)

机构地区：[1]龙岩学院资源工程学院,福建龙岩364012 [2]同济大学测绘与地理信息学院,上海200092 [3]滁州学院地理信息与旅游学院,安徽滁州239000

出　　处：《测绘科学》2018年第7期121-127,共7页Science of Surveying and Mapping

基　　金：福建省测绘地理信息科技发展基金项目(2016JX05);福建省自然科学基金项目(2018J0106);福建省省级大学生创新训练计划项目(201511312061)

摘　　要：针对近景视频摄影测量中椭圆标志点的中心定位精度影响后续的目标跟踪和三维重建精度的问题,该文为了保证获取椭圆亚像素的中心定位精度,提出了一种基于椭圆标志点亚像素边缘检测的中心定位方法。该方法首先利用Canny算子提取椭圆的轮廓,然后利用阈值分割、形态学边缘轮廓提取方法等方法对边缘进行约束,再利用形态学细化算法和空间矩提取椭圆的亚像素边缘,最后利用最小二乘拟合法实现椭圆中心的亚像素定位。实验结果表明:在模拟实验和真实影像的实验下,该方法与现有其他方法相比较,不仅能获取和定位高精度的椭圆中心(模拟实验下,椭圆中心定位精度高达0.02像素),而且具有高稳健性;能够满足近景摄影测量的精度和稳定性的需求。The central positioning accuracy of elliptical target points in close-range photogrammetry affects the accuracy of subsequent target tracking and 3 Dreconstruction.In order to obtain the sub-pixel accuracy,aproposed method of central location based on sub-pixel edge detection of elliptical target points,are proposed.Firstly,the edge contour of the ellipse is extracted by using the Canny operator,and the edges are constrained by a series of methods of threshold segmentation,morphological edge contour extraction,etc.Then,the morphological refinement algorithm and the spatial moment are used to obtain the sub-pixel edge of the ellipse.Finally,sub-pixel accuracy of localization is determined by Least Mean-square algorithm with ellipse fitting.The experimental results showed that the proposed method not only can obtain the high precision center location of elliptical target point（the accuracy of elliptical center location is as high as 0.02 pixels under different simulation experiment）,but also has the strong robustness,which indicates that the improved method satisfies the accuracy requirement of close-range photogrammetry.

关 键 词：近景视频摄影测量 椭圆标志 亚像素检测 亚像素定位 

分 类 号：P258[天文地球—测绘科学与技术]