提高局部信噪比的单帧红外图像非均匀性校正方法  

A Non-uniformity Correction Method with ImprovedLSNR for Single-Frame Infrared Image

作　　者：赵云[1] 朱鑫鑫 桑苗苗 何宇[1] ZHAO Yun;ZHU Xinxin;SANG Miaomiao;HE Yu(No.63618 Unit of PLA,Korla 841000,China)

机构地区：[1]中国人民解放军63618部队,新疆库尔勒841000

出　　处：《电光与控制》2023年第10期114-119,共6页Electronics Optics & Control

摘　　要：针对红外图像存在的非均匀性问题,从理论上对非均匀性产生的原因进行了分析。对基于SG滤波预处理的无模型图像校正EM算法进行改进,提出了一种提高局部信噪比的单帧图像校正方法。设计了对比实验,在红外目标、暗弱目标和云层背景场景下,该方法能使红外图像的非均匀性(NU)分别降低56.869 3%,85.938 4%和87.886 3%,同时,LSNR分别提高了3.687 7 dB,0.256 9 dB和3.553 1 dB。最后在非均匀背景上叠加高斯分布的目标进行模拟,探讨了目标大小与滤波窗口的关系,得到了滤波窗口与红外小目标的近似关系为H≈4.6*S_T+0.3,从实际工程应用上确定了该方法滤波窗口初值的选取。结果表明,所提方法能在LSNR最大的前提下,利用单帧红外图像的场景信息对非均匀性进行有效校正。As for the non-uniformity of infrared images,the causes of occurrence of non-uniformity are analyzed theoretically.The EM algorithm of model-free image correction based on SG filter pretreatment is improved,and a single-frame image correction method of improving LSNR is proposed.A comparative experiment is designed,under the scenes of infrared target,dim target and cloud background,the method can reduce the non-uniformity(NU)of the infrared image by 56.8693%,85.9384%and 87.8863%respectively,and increase the LSNR by 3.6877 dB,0.2569 dB and 3.5531 dB respectively.Finally,the Gaussian-distributed target is superimposed on the non-uniformity background for simulation,and the relationship between the size of the target and the filtering window is discussed.The approximate relationship between the filtering window and the small infrared target is obtained as follows:H≈4.6*S T+0.3,and the selection of the initial value of the method's filtering window is determined from practical engineering applications.The results show that the proposed method can effectively correct the non-uniformity by using the scene information of a single-frame infrared image on the premise of maximum LSNR.

关 键 词：红外图像 非均匀性校正 局部信噪比 SG滤波 

分 类 号：TN215[电子电信—物理电子学]