基于互相关和改进高斯拟合的光斑中心提取方法  

Spot center extraction based on cross correlation and improved Gaussian fitting

作　　者：吴頔[1,2] 吕且妮[1,2] 卢琳[1,2] 陈曦[3] 葛宝臻[1,2] 

机构地区：[1]天津大学精密仪器与光电子工程学院,光电信息技术教育部重点实验室,天津300072 [2]光电信息技术教育部重点实验室,天津300072 [3]天津大学电气与自动化工程学院,天津300072

出　　处：《光电子．激光》2017年第2期202-210,共9页Journal of Optoelectronics·Laser

基　　金：国家“863”高技术项目(2008AA09Z115);海洋公益性行业科研专项经费项目(201305002-2)

摘　　要：针对差分激光三角法海面溢油油膜厚度测量系统中光斑图像中心提取的问题,在分析用于系统标定的陶瓷量块和所测量的石油表面光斑图像特征的基础上,采用互相关与改进型高斯拟合的算法对光斑中心进行提取。算法首先采用标准高斯图像模板与光斑图像进行互相关,得到了保留图像特征且光顺的光斑图像;然后,利用上下边沿信息进行高斯计算的改进型高斯拟合方法进行光斑图像拟合,由拟合得到的高斯图像参数计算出光斑中心坐标。通过本算法与目前已有的平方加权质心法、高斯拟合法、改进型高斯拟合法和互相关高斯拟合法对图像光斑中心提取结果的比较与分析,得出互相关和改进高斯拟合相结合的方法在光斑提取重复性精度,以及使用本算法对陶瓷量块厚度测量精度均好于其它方法,并对石油表面图像进行了中心提取实验。结果表明,本文算法适合于差分激光三角法海面溢油油膜厚度测量系统的光斑提取。According to extracting the center coordinate of spot in an oil film thickness measurement sys- tem with differential laser triangulation, based on the analysis on spot image features of ceramic gauge block and oil film,a method of spot positioning is presented with cross correlation and improved Gaussian fitting. The smooth and feature reserved spot image is obtained through the correlation operation of the spot image and a Gaussian mask image. The center coordinate of the spot image is obtained by improved Gaussian fitting with the ascending edge and descending edge data of the correlation results extracted for fitting. To verify the performance of the method, experimental measurement is carried out with different spot center extraction methods. Compared with square weighted centroid method,Gaussian fitting meth- od,improved C-aussian fitting method and cross correlation Gaussian fitting method, the precision of the presented mothod is higher. The experiment of oil film spot center extraction is carried out. The results show that the algorithm presented is feasible for oil film thickness measurement system with differential laser triangulation.

关 键 词：激光三角法 光斑中心提取 互相关 改进型高斯拟合 

分 类 号：TN248[电子电信—物理电子学]