摘要
分析了表面粗糙度、几何角度和极化方式对水体等地物在雷达图像上成像特点的影响因素以及纹理特征对水体提取的作用,分别对基于单波段数据的域值法、基于双极化数据的最大似然分类法和基于双极化数据和纹理信息的最大似然分类法从ENVISAT-ASAR数据提取洪涝水体信息的方法进行了分析与探讨。试验结果表明:域值法提取水体,存在很多诸如山体阴影等易与水体混淆的误提取问题;利用双极化数据并加入纹理信息参与水体信息提取,在一定程度上可以改善这种误提取现象,提高水体提取精度。纹理的选择方法要与当地的水体与山体阴影走向、形态等结合,这个试验过程是费时的。
Flood water body area is one of the most important information on Real-time Momitoring and quick evaluation of flood damage. The single band radar image can extract flood water body easily by using the threshold method, but it is difficult to differentiate the flood water body from the mountain shadow with single band. Based on the analysis of surface roughness, angle of incidence, texture information and polarization way which influence the backscatter characters of water in radar image, we try to utilize the dual polarized ENVISAT - ASAR data and texture information to solve the problem. The experiment result indicates that the flood information can be obtained more effectively, accurately and rapidly in the use of presented methods than the threshold method. The methods reduce the phenomenon of confusion between flood water body and mountain shadow to some extent and enhancing the water body extracting precision.
出处
《自然灾害学报》
CSCD
北大核心
2009年第4期120-124,共5页
Journal of Natural Disasters
基金
科技部资助项目(2003DKA1T007)
关键词
雷达图像
双极化
纹理
水体
radar image
dual polarization
texture
water body
