小波滤噪对多光谱遥感水深反演精度的影响分析  

Impact of Wavelet Denoising on Multi-Spectral Bathymetry Inversion

作　　者：张靖宇[1] 马毅[1] 田震[1,2] 梁建[1] 

机构地区：[1]国家海洋局第一海洋研究所,山东青岛266061 [2]山东科技大学测绘科学与工程学院,山东青岛266590

出　　处：《海洋科学进展》2015年第3期334-341,共8页Advances in Marine Science

基　　金：国家科技支撑计划项目--远海岛礁地理信息监测关键技术研究与示范(2012BAB16B01-02);国家海洋局青年海洋科学基金项目--远离大陆海岛的国产自主测绘卫星影像几何校正技术研究(2013441);中央级公益性科研院所基本科研业务费专项--远离大陆海岛的无少控制点定位技术研究(2013G37)

摘　　要：为了深入探究小波滤噪尺度与多光谱遥感水深反演精度间的关系,本文以西沙东岛周边20m以浅海域为实验区,选用WorldView-2多光谱影像和实测水深为反演数据源,开展了基于三波段对数线性模型的实验区原始影像及一级至五级小波滤噪后影像的遥感水深反演实验,并从总体、分段和不同滤噪方法的反演精度对比三个方面进行了分析。结果表明:1)小波滤噪后影像较原始影像反演精度要高,反演精度最高的是三级小波滤噪影像,其平均相对误差为27.5%,平均绝对误差为1.1m。2)随着深度增加,小波滤噪前后影像水深反演的平均相对误差均减小,平均绝对误差先减小后增大;较小尺度小波滤噪适用于浅水区,而较大尺度小波滤噪适用于深水区。3)当窗口较小时,小波滤噪或均值滤波影像的水深反演精度均优于中值滤波;当滤噪强度增加到一定程度时,3种滤波方法在反演精度上均表现出提升减缓甚至开始降低的趋势。This paper investigated the impact of different order wavelet denoising on bathymetry inversion accuracy of multi-spectral remote sensing.Waters with depths ranging from 0 mto 20 maround Xisha Dongdao were selected as the study area,and WorldView-2multi-spectral image along with the measured water depth were collected.Based on log-linear model of three bands for bathymetry inversion,the following results were found：1）Inversion accuracy of the images after wavelet denoising was higher than that of the original image,and the third order wavelet denoising showed the best performance with the mean relative error of 27.5% and the mean absolute error of 1.1m.2）With the increase of water depth,the mean relative error of the inversion results from both the original and wavelet denoising images decreased,but the mean absolute error decreased followed by an increase.Wavelet denoising with smaller and higher orders was applicable to the shallow water and deep water conditions,respectively.3）Given the smaller denoising window,the inversion accuracies of wavelet denoising and mean filter were similar,and better than that of median filter.When the denoising intensity increased to certain degree,inversion accuracies of all the three denoising approaches increased with a smaller rate or even began to descend.

关 键 词：小波变换 水深反演 WorldView-2 

分 类 号：TP751[自动化与计算机技术—检测技术与自动化装置]