面向弱光探测的实时像元合并  

Real-time pixel merging for weak light detection

作　　者：张刘[1] 王亚明 张文 王文华 ZHANG Liu;WANG Ya-ming;ZHANG Wen;WANG Wen-hua(College of Instrument Science and Electrical Engineering,Jilin University,Changchun 130021,China)

机构地区：[1]吉林大学仪器科学与电气工程学院,吉林长春130021

出　　处：《光学精密工程》2021年第11期2539-2547,共9页Optics and Precision Engineering

基　　金：科技部重点研发计划资助项目(No.2016YFB0501000,No.2016YFB0501002);科工局国防基础科研重点突破项目;装备预研领域基金资助项目(No.JZX7Y20190254047001);上海航天科技创新基金资助项目(No.SAST2018046);国防基础科研计划资助项目(No.JCKY2019110)。

摘　　要：为解决弱光环境下月球着陆粗避障环节成像不清晰的问题,提出了“区域”像元合并和去除相机本底值两种图像预处理方法,来提高探测器的成像灵敏度和图像信噪比与对比度。在分析传统像元合并实现原理的基础上,提出了一种针对n_taps成像数据格式的“区域”像元合并方法。根据月球着陆粗避障环节中大尺度障碍识别的特点,通过去除相机本底值来提高图像的对比度。最后,利用宽、窄视场两款相机分别对像元合并、去除相机本底值以及两者结合的方法进行了重复性实验。实验结果表明,在弱光环境下,结合像元合并与去除相机本底值的方法可有效提高图像的信噪比与对比度,2_Binning模式下宽视场相机的信噪比可提高5.9014 dB、对比度可提高0.2547,窄视场相机的信噪比可提高5.7644 dB、对比度可提高0.2654;4_Binning模式下宽视场相机的信噪比可提高11.6899 dB、对比度可提高0.2102,窄视场相机的信噪比可提高11.4015 dB、对比度可提高0.2840。In order to solve the problem of unclear images in the rough obstacle avoidance link of lunar landing in weak light environments,this study proposes two image preprocessing methods,namely"region"pixel binning and camera background value removal,to improve the imaging sensitivity,image signal-to-noise ratio(SNR),and contrast ratio of lunar landing.First,based on the analysis of the principle of traditional pixel binning,a region pixel binning method based on the n_taps imaging data format is proposed.Then,according to the characteristics of large-scale obstacle recognition in lunar landing rough obstacle avoidance,the image contrast is improved by removing the background value of the camera.Finally,the methods of pixel binning,camera background removal,and the combination of the two methods are repeated using two cameras that have wide and narrow fields of view.The experimental results show that the SNR and contrast of images can be improved effectively by combining pixel merging and camera background value removal under weak light environments.In 2_Binning mode,the SNR and contrast of the camera with a wide field of view can be improved by 5.9014 dB and 0.2547,respectively,and the SNR and contrast of the camera with a narrow field of view can be improved by 5.7644 dB and 0.2654,respectively.In 4_Binning mode,the SNR and contrast of the camera with a wide field of view can be improved by 11.6899 dB and 0.2102,respectively,and the corresponding values for a camera with a narrow field of view can be improved by 11.4015 dB and 0.2840,respectively.

关 键 词：弱光探测 像元合并 相机本底值 多项式拟合 

分 类 号：TH74[机械工程—光学工程] TH75[机械工程—仪器科学与技术]