一种改进的基于暗原色先验信息的航空遥感图像去雾方法  

An Improved Aerial Remote Sensing Image Defogging Method Based on Dark Channel Prior Information

作　　者：张正豪 冯伍法[1] 王涛[1] 张艳[1] 窦利军 ZHANG Zhenghao;FENG Wufa;WANG Tao;ZHANG Yan;DOU Lijun(Information Engineering University,Zhengzhou 450001,China;61363 Troops,Xi＇an 710000,China)

机构地区：[1]信息工程大学 [2]61363部队

出　　处：《测绘科学技术学报》2018年第2期182-186,共5页Journal of Geomatics Science and Technology

基　　金：十三五预研项目(30503040203;30503040501);国家自然科学基金项目(41501482)

摘　　要：航空遥感图像以其分辨率高、信息丰富和易于解析处理等优点而得到广泛应用。但是其成像易受云雾天气的影响,特别是在近几年我国雾霾进一步加重的情况下尤为明显。针对航空遥感图像数据含雾较为均匀且不包含天空区域的特点,提出一种改进的基于暗原色先验信息的航空图像的去雾方法。首先,对图像进行2%线性拉伸处理改善图像的视觉效果;随后通过直接计算每个像素点R、G、B的3个颜色通道的最小值求取图像暗原色图;同时由航空图像的特殊性自适应地设置阈值来改善去雾图像效果;最后对去雾后图像采用自动色阶法进行进一步处理,改善暗原色法去雾后图像过暗或者偏色问题。利用不同航空含雾图像进行去雾实验并进行对比分析,结果表明,改进算法能够平衡去雾后图像的色彩使其避免产生偏色现象,获得质量和视觉效果更好的去雾图像。Aerial remote sensing image is widely used due to its high resolution,abundant information and convenient processing. However,its image quality is easily influenced by clouds and fog. In recent years,fog and haze air pollution is becoming more and more serious in the north of China and its influence on aerial remote sensing image quality is especially obvious. Considering the characters that the fog in aerial remote image is usually uniform and the image seldom covers sky area,an improved aerial remote sensing image defogging method based on dark channel prior information is proposed in this paper. Firstly,a 2% linear stretching is applied to eliminate the haze offset effect and provide a better initial value for later defogging processing. Then the dark channel prior image is obtained by calculating the minimum values of R,G,B channels of each pixel directly. Subsequently,the adaptive threshold is set up to improve the defogging effect according to the particularity of aerial image. Finally,a way called automatic color method is introduced to enhance the visual effect of defogged image to improve the color cast phenomenon. Experiments are performed on different aerial remote sensing images in fog. Experimental results prove that the proposed method can balance the color information in the defogged image and efficiently avoid the color cast phenomenon and obtain the defogged image with better visual effect and image quality.

关 键 词：航空遥感 去雾 暗原色先验 线性拉伸 自动色阶 

分 类 号：P237[天文地球—摄影测量与遥感]