纳米颗粒成像自动对焦评价算法  

Autofocus Evaluation Algorithm for Nanoparticle Imaging

作　　者：汪路涵 巩岩[2] 张艳微 高若谦 郎松 曹选 Wang Luhan;Gong Yan;Zhang Yanwei;Gao Ruoqian;Lang Song;Cao Xuan(Division of Life Sciences and Medicine,School of Biomedical Engineering(Suzhou),University of Science and Technology of China,Suzhou 215163,Jiangsu,China;Medical Optical Research Laboratory,Suzhou Institute of Biomedical Engineering and Technology,Chinese Academy of Sciences,Suzhou 215163,Jiangsu,China;School of Physical Science and Technology,Suzhou University of Science and Technology,Suzhou 215009,Jiangsu,China)

机构地区：[1]中国科学技术大学生物医学工程学院(苏州)生命科学与医学部,江苏苏州215163 [2]中国科学院苏州生物医学工程技术研究所医用光学技术研究室,江苏苏州215163 [3]苏州科技大学物理科学与技术学院,江苏苏州215009

出　　处：《激光与光电子学进展》2023年第4期255-261,共7页Laser & Optoelectronics Progress

基　　金：国家自然科学基金(61975228,62005307);中国科学院科研仪器设备研制项目(YJKYYQ20180032);济南高校“20条”(2019GXRC042);苏州市姑苏重大创新团队(ZXT2019007)。

摘　　要：纳米颗粒成像过程中,离焦位置的粒子团簇和大颗粒杂质产生明亮的弥散斑,导致现有的对焦算法无法实现自动对焦功能。利用基于大津算法的二值化分割和形态学开闭方法,使离散的弥散斑聚合为一个区域,并利用连通域标记方法筛选剔除大面积的光斑区域,构造四邻域水平-对角平方函数和阈值四邻域水平-对角开方函数,将函数分别作为粗对焦和精对焦的评价指标,提高了自动对焦搜索的准确性和可靠性。实拍离焦序列图,并与5种常用的评价算法进行对比,结果表明所提自动对焦评价算法具有良好的鲁棒性、无偏性和单峰性。In nanoparticle imaging,particle clusters and large impurity particles in the defocused position cause bright spots,thus hindering the existing focusing algorithms in realizing the autofocus function.This study used binarization segmentation based on the Otsu algorithm,as well as morphological opening and closing methods,to aggregate the dispersed diffuse spots into one area.Furthermore,the connected domain labeling method was used to filter out large regions of the spot area.A fourneighborhood leveldiagonal square function and thresholdfourneighborhood leveldiagonal square root function were constructed and used as the evaluation indicators for the coarse and fine focus,respectively,thereby improving the accuracy and reliability of autofocus search.The defocus sequence diagram was obtained and the proposed algorithm was compared to the five commonly used evaluation algorithms.The results demonstrate that the proposed autofocus evaluation algorithm is highly robust,unbiased,and unimodal.

关 键 词：图像处理 纳米颗粒 自动对焦 评价算法 连通域标记 

分 类 号：TP391[自动化与计算机技术—计算机应用技术]