摘要
分析了SAR图像的基本特点 ,阐述用DFBR模型表达SAR图像的基本原理 ,提出两种基于分形理论的SAR图像边缘检测方法。通过对传统方法、分形方法和多尺度分形方法的特性分析和实验 ,说明分形方法有较强的抗干扰性能 ,适用于SAR图像的边缘检测 。
After discussing the SAR images' properties and the principles of image description with discrete Fractional Brownian incremental random field model(DFBR model),this paper presents two new methods of edge detection for SAR images based on the Fractal theory. It is known that the Fractal Brownian random model is valid to describe the image of nature scene.In one tiny region of image, the gray surface is self similar to statistics.But for the edge points ,the point located in the boundaries between adjacent regions,this property will be lost.And the Fractal parameters of these points will be out of range.So we can determine whether the point of image is edge point via calculating its Fractal parameters.A new fast method to calculate the Fractal dimension and the principles of determining edge point based on single Fractal dimension are discussed in this paper. Moreover,the Fractal parameters of image points must not depend on the scale.But for the edge points,because they have lost the self similar,their Fractal parameters will change more quickly with the scales than the other points.So we can estimate the points' Fractal parameters in different scales and caculate their difference matrix(edge magnitude map).Then we can obtain binary edge image by thresholding this edge map. In the end,the authors present experimental results of edge detection of a SAR images with the Sobel operator,the Prewitt operator,and these two methods are mentioned above.After analyzing the experimental results in detail,the authors draw the conclusion: these two new methods have better ability to anti noise for SAR images edge detection.And the second method,the Multifractal Method,get better results of edge detection than the first method,the single fractal method.
出处
《武汉测绘科技大学学报》
CSCD
2000年第4期334-337,共4页
Geomatics and Information Science of Wuhan University
关键词
SAR图像
边缘检测
多尺度分形
SAR image
edge detection
DFBR model
multifractal dimension
