首页 | 本学科首页   官方微博 | 高级检索  
     检索      

一种基于小波变换的SAR图像边缘检测器(英文)
引用本文:杨莉,袁信.一种基于小波变换的SAR图像边缘检测器(英文)[J].南京航空航天大学学报(英文版),2001,18(1).
作者姓名:杨莉  袁信
作者单位:南京航空航天大学自动化学院
摘    要:边缘提取是图像处理与图像分析的基础。本文基于小波变换 ,研究了 SAR图像边缘提取的方法 ,从而为合成孔径雷达 (SAR)图像辅助导航系统奠定基础。由于 SAR图像受固有斑点噪声的影响 ,采用小波变换与固定阈值提取 SAR图像边缘特征时 ,将有大量虚假边缘产生 ,特别是在图像的亮区。为此 ,本文提出了采用具有恒定误警率的阈值 ,以消除斑点噪声的影响。同时 ,分别对两幅不同的图进行仿真 ,仿真结果表明 ,斑点噪声的影响被大大抑制 ,且由于阈值是由小波变换系数直接构成 ,能保证辅助导航对实时性的要求。

关 键 词:合成孔径雷达  斑点噪声  小波变换  边缘检测器  导航

AN EDGE DETECTOR BA SED ON WAVELET TRANSFORM FOR SAR IMAGE
Yang Li,Yuan Xin.AN EDGE DETECTOR BA SED ON WAVELET TRANSFORM FOR SAR IMAGE[J].Transactions of Nanjing University of Aeronautics & Astronautics,2001,18(1).
Authors:Yang Li  Yuan Xin
Institution:Yang Li Yuan XinCollege of Automation Engineering,NU)29 Yudao Street,Nanjing 210016,P.R.China
Abstract:Edge detecting is a f undamental issue in image analysis and image processing. In this paper, based on wavelet transform, an edge detector of SAR image is studied to serve the image aided navigation. Though wavelet transform is efficient as an edge detector, a l ot of false edges will be extracted from a SAR image, especially in areas of hig h reflectivity, with wavelet transform and a fixed threshold because SAR images are always contaminated by speckle. Therefore, this paper develops an algorithm by using a variable threshold with constant false alarm rates to help suppressin g the speckle in SAR images. Finally, two simulating tests are given and the res ults show that the effect of the multiplicative speckle is controlled and there are few false edges in the gotten edge images. Moreover, owing to the threshold from the wavelet transform coefficients, the algorithm can assure the real time of SAR image aided navigation.
Keywords:SAR  speckle  wavelet t ransform  edge detector  navigation
本文献已被 CNKI 万方数据 等数据库收录!
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号