线结构光光条中心亚像素精确提取方法  

Extrication Method for Sub-Pixel Center of Linear Structured Light Stripe

作　　者：江永付 江开勇[1] 林俊义[1] 

机构地区：[1]华侨大学厦门市数字化视觉测量重点实验室,福建厦门361021

出　　处：《激光与光电子学进展》2015年第7期179-185,共7页Laser & Optoelectronics Progress

基　　金：国家科技支撑计划(2012BAF12B15);福建省科技计划重点项目(2008H0085);福建省自然科学基金(2013J01190);厦门市科技计划项目(3502Z20143042)

摘　　要：线结构光三维测量中,光条中心点提取的精度直接影响系统最终测量精度。针对现有光条中心提取方法获得的条纹中心存在折线缺陷的问题,提出了一种基于曲线拟合的线结构光光条中心的亚像素提取方法。该方法通过腐蚀细化获得光条基本骨架,采用均方灰度梯度求取骨架上每一点的法线方向,利用加权灰度重心法获得光条中心初始点,应用分段3次多项式曲线拟合获得光滑的光条亚像素中心坐标。实验结果表明:该方法可以改善光条中心的折线缺陷,提高中心线提取的精度。In the three-dimensional measurement based on the linear structured light projection, the extraction precision of light stripe center affects the ultimate measurement accuracy of system directly. Aiming at the problem of broken line defect which exists in stripe center acquired from current light stripe center extraction algorithms, an proposed approach based on curve fitting of the linear structured light stripe center sub-pixel extraction is proposed. The proposed approach uses the erosion thinning method to get the stripe＇s basic skeleton. The normal direction of each point on the skeleton line is computed by using the average squared gray gradient. The initial light stripe central points are obtained by weighted barycenter method. Sectional cubic polynomial curve fitting method is used to achieve smooth light stripe central positions in sub-pixel. The experimental results show that this method can improve the broken line defect and the accuracy of light stripe center extraction.

关 键 词：测量 线结构光 光条骨架 均方灰度梯度 多项式曲线拟合 

分 类 号：TP391[自动化与计算机技术—计算机应用技术]