高分辨率遥感影像快速去雾

针对含雾遥感影像在军事航空侦查、地物判读等方面使用率低、有效性差的问题，以及现有去雾算法中存在计算复杂耗时、色彩失真的弊端，结合遥感影像景深变化小、不含天空背景等特点，本文提出一种改进的暗原色先验去雾算法。首先，对影像中白色场景灰度值进行统计并设定阈值划分为失效区，分离水域与非水域减少蓝色波段在水域的占比，合成新的蓝色波段，以改进暗通道值的获取方法；其次，采用导向滤波替代软抠图法优化透射率提升处理时间；然后，对关键参数进行适应性改进试验并采用自动色阶恢复去雾后的影像色彩；最后，利用含雾的无人机影像和GF-2影像进行了试验，并进行了定量评价。试验结果表明，在同等试验条件下，本文方法处理单幅影像的时间比暗原色先验去雾算法的提升4倍以上，且去雾后影像的灰度均值、标准差、信息熵、平均梯度等指标比暗原色先验去雾算法得到的值均有提高，能有效提高有雾影像的清晰度，增强影像色彩和细节。

Fast dehaze of high resolution remote sensing images

Aiming at the problems of low utilization rate and poor effectiveness of cloud and fog remote sensing images in military aviation investigation and ground object interpretation, as well as the disadvantages of the existing cloud and fog removal algorithms, such as complex calculation, time-consuming and color distortion, combined with the characteristics of remote sensing image with small depth of field change and without sky background, an improved dark-channel prior dehazing algorithm is proposed. Firstly, the gray value of the white scene in the image is counted and the threshold is set to divide it into failure area. The water area and non water area are separated to reduce the proportion of blue band in the water area, and a new blue band is synthesized to improve the acquisition method of dark channel value; Secondly, the guided filter is used to replace the soft matting method to optimize the transmittance enhancement processing time; then, the adaptive improvement experiment of key parameters is carried out and the automatic color level restoration is adopted the color of the image after defogging. Experiments are carried out with fog UAV images and GF-2 images, and quantitative evaluation is carried out. The experimental results show that under the same experimental conditions, the processing time of a single image by this method is more than 4 times higher than that of the dark-channel prior algorithm, and the gray mean, standard deviation, information entropy and average gradient of the dehaze image are higher than those obtained by the dark-channel prior algorithm, which can effectively improve the clarity of the fogged image, Enhance image color and detail.