川中地区资源三号卫星影像去云技术研究

为让“资源三号测绘卫星”更好地为四川省地理省情、地质灾害监测等提供服务,应利用已有资源三号卫星影像为数据源,针对被薄云污染的卫星影像展开去云技术的研究：（1）依据单波段影像的频率特性采用同态滤波算法抑制低频、增强高频,实现了薄云的滤除;（2）依据多光谱影像的光谱特性,借助ENVI/haze tool工具,采用改进HOT算法探测云层厚度,再通过多种地物掩膜再内插云层厚度的方式完善云层厚度影像;（3）选择虚拟云点算法实现了云层厚度的探测和完善,并获取了云层消除影像.结果表明：该方法对于去除川中丘陵浅山区资源三号影像中的薄云具有良好效果.

Study on Cloud Removing on Ziyuan-3 Image with Thin Cloud in the Foothill of Middle Sichuan Area

Ziyuan-3 Surveying Satellite was lunched on January, 2012. In order to provide better service for the monitoring of province geographic condition and geologic hazard in Sichuan Province, this paper studied on the cloud removing on the Ziyuan-3 image with thin cloud. This study studied the cloud removing for single and multiple remotely bands, including. 1. Suppression of the low-frequency and enhancement of high-frequency using homomorphic filtering according to the frequency character of the single-image-band to remove thin cloud, and 2. Using improved HOT algorithm to detect the cloud thickness, and improving the cloud thickness image by masking and interpolation of cloud thickness, and detecting the cloud thickness using virtual cloud point algorithm. Results show that the proposed method can remove thin cloud in the Ziyuan-3 remotely sensed image in the foothill of the middle Sichuan province area effectively.