一种基于幂指数拉伸的去雾算法  

Defogging Algorithm Based on Power Exponent Stretching

作　　者：李忠国[1] 吴昊宸 付启高 席茜 吴金坤 LI Zhongguo;WU Haochen;FU Qigao;XI Qian;WU Jinkun(College of Mechanical Engineering,Jiangsu University of Science and Technology,Zhenjiang 212000,China;Guizhou Fenglei Aviation Armament Co.,Ltd.,Anshun 561000,China)

机构地区：[1]江苏科技大学机械工程学院,镇江212000 [2]贵州风雷航空军械有限责任公司,安顺561000

出　　处：《数据采集与处理》2022年第1期62-72,共11页Journal of Data Acquisition and Processing

基　　金：国家重点研发计划(2018YFC0309100)。

摘　　要：比较同一场景无雾和有雾时图像RGB(Red-green-blue)三通道和HSV(Hue-saturation-value)三通道的变化,提出一种基于幂指数拉伸的去雾算法。首先将图像从RGB变换到HSV空间,将饱和度分量和亮度分量分别作1~3的幂指数拉伸和调整,将拉伸变换后分量生成HSV图像再变换到RGB空间,生成增强后的去雾图像。以饱和度均值、亮度指标、信息熵和对比度作为去雾评价的指标,确定最优的拉伸幂指数组合。然后使用最优幂指数完成去雾处理,同时根据图像饱和变化的阈值或时间间隔长度决定是否重新寻找最优拉伸幂指数。最后使用Python软件,借助多进程编程实现本文去雾算法。当图像分辨率为400像素×300像素时,树莓派上运行时幂指数参数寻优用时为5.077~6.160 s,单帧图像去雾用时第1帧时间长为0.308 s,其余时间为0.077~0.168 s,结果验证了本文算法的实时性。After comparing three channels of RGB(Red-green-blue)and three channels of HSV(Hue-saturation-value)in the same scene between clear and fog pictures,a haze removal algorithm based on power exponent stretching is proposed.Firstly,the image is transformed from RGB to HSV space.Then the saturation component and the brightness component are exponentially stretched with power of 1—3,and then they are both adjusted to their suitable range.After stretching transformation of saturation and brightness,the image is transformed from HSV to RGB space to generate enhanced defogging images.Taking the mean value of saturation,brightness index,information entropy and contrast as defog evaluation indexes,the optimal stretching power index combination is determined.The optimal power index combination is used to complete the defogging process.At the same time,it is decided whether to find the optimal power index again according to the change of image average saturation or the length of time interval.Finally,the fog removal algorithm is implemented by multi-process programming with the Python software.When the image resolution is 400 pixel×300 pixel,it takes 5.077—6.160 s to optimize the power index parameters on the raspberry PI.For one frame defogging,the first frame takes longer time of0.308 s.The other frames take 0.077—0.168 s to removal haze for a single frame.

关 键 词：去雾增强 HSV空间 幂指数拉伸 去雾评价 多进程编程 

分 类 号：TP391[自动化与计算机技术—计算机应用技术]