第19卷
第3期
2011年3月
文章编号
1004-924X(2011)03-065707
光学精密工程
Optics and Precision Engineering
Vol. 19No, 3
Mar.2011
基于似然函数EM迭代的红外与可见光图像配准
聂宏宾，侯晴宇，赵明，张伟
（哈尔滨工业大学空间光学工程研究中心，黑龙江哈尔滨150001）
摘要：为了实现红外与可见光图像的自动配准，提出了基于似然函数EM选代的图像配准算法。该算法以图像边缘作为配准点特征，将异源图像配准转化为边缘点集配准。通过点集的高斯混合建模建立了点集配准似然函数；以该函数作为目标函数，仿射变换参数作为优化变量，利用EM选代优化方法进行最优变换参数求解。选代过程中，引人基于概率密度自适应阀值分割的外点别除机制，解决了外点对目标函数的干扰间题，实现了边缘点集的精确配准。利用实测的可见光和红外图像进行了算法验证，证明了该算法的有效性。
关键调：红外图像；可见光图像；图像配准；仿射变换；EM速代
中图分类号：TP391
文献标识码：A
doi;10.3788/OPE.20111903.0657
IR/visibleimageregistration based
on EMiteration oflog-likelihoodfunction NIE Hong-bin, HOU Qing-yu, ZHAO Ming, ZHANG Wei
(Research Centerfor SpaceOptical Engineering,
Harbin Institute of Technology,Harbin 15000l,China)
Abstract: In order to realize the automatic image registration for infrared images and visible images, an image registration method based on the Expectation Maximum(EM) iteration of the log-likelihood function is proposed.This method utilizes the image edge as the registration point, and thus the image registration is transferred into an edge point set registration. The point set is modeled as Gauss Mix ture Model (GMM), and the likelihood function of the point set registration is obtained. To solve the affine transform parameter, the likelihood function is maximized with EM iterations. And during the EM iterations, the probability density of edge point is segmented with an adaptive threshold to elimi-nate the outer points, and the interference of outer point with the likelihood function is overcome and the affine transform parameter is determined accurately. The experiments on image registration for in-frared images and visible images are verified, and the results indicate that the proposed method is effec tive
Key words: infrared image; visible image; image registration; affine transform; Expectation Maximum
(EM）iteration
收稿日期：2010-09-25；修订日期；2010-12-31，基金项目：基础科研资助项目(No.k1402060311)