基于小波分析的sar影像相干斑点噪声滤除方法的研究.doc

目录

摘要

Abstract
第一章 引言...........................................................................................................1
1．1研究的目的和意义...................................................................................1
1．2国内外研究现状.......................................................................................1
1．3研究的内容...............................................................................................3
第二章 斑点噪声的形成原理与斑点噪声模型...................................................4
2．1斑点噪声的形成原理...............................................................................4
2．2斑点噪声的特征.......................................................................................5
2．2．1斑点噪声的概率分布函数.............................................................5
2．2．2斑点噪声的自相关函数.................................................................5
2．2．3斑点噪声的功率密度谱.................................................................5
2．3斑点噪声模型...........................................................................................6
2．3．1 Rayleigh斑点噪声模型..................................................................6
2．3．2乘性噪声模型.................................................................................6
第三章 滤波方法发展的回顾...............................................................................9
3．1空间域的滤波方法...................................................................................9
3．1．1传统方法.........................................................................................9
3．1．2局域统计自适应滤波.....................................................................9
3．2频率域的滤波方法.......................................................................................12
3．2．1Fourier变换方法................................................................................12
3．2．2基于小波分析的方法.........................................................................12
第四章 基于小波分析的SAR影像去噪的原理和方法......................................16
4．1小波变换及其特性.....................................................................................16
4．1．1小波变换........................................................................................16
4．1．2多尺度分析与正交小波变换........................................................17
4．1．3双正交小波变换..........................................................................19
4．2随机噪声的小波变换特性......................................................................20
4．1．1模极大值与信号奇异度和尺度的关系....................................20
4．1．2模极大值传播特性....................................................................21
4．3小波基的选择..........................................................................................21
4．4应用多尺度小波变换进行SAR影像去噪.............................................22
4．4．1小波分解变换...........................................................................23
4．4．2小波多尺度去噪.......................................................................24
4．4．3小波逆变换重构原图像...........................................................25
第五章 滤波器性能评价.....................................................................................26
5．1评价的基本思想............................................................................................26
5．2评价的方法和标准.......................................................................................26
5．2．1斑点噪声的滤除能力......................................................................26
5．2．2边缘的保持能力.............................................................................26
5．3滤波器性能的评价 ......................................................................................26
5．3．1影像的比较......................................................................................27
5．3．1．1条带、点目标和随机噪声模拟的SAR影像的比较.......27
5．3．1．2 Radarsat影像的比较........................................................30
5．3．2滤波器性能的定量评价..................................................................32
5．3．2．1均值的保留能力.................................................................32
5．3．2．2噪声的滤除能力................................................................33
5．3．2．3边缘的保持能力................................................................34
5．3．2．4线和点目标的保持能力....................................................35
5．3．2．5自然的目视效果...................