Edge Extraction Algorithm of SAR Image Using Random Direction Symmetric Difference Kernel
Due to the noise sensitivity and limited directivity of extracted edge presented in current edge detection algorithms, it is difficult to effectively extract the edges with any direction between the two regions with similar intensities from SAR images. In this paper, an edge extraction algorithm of...
| Main Authors: | , , , |
|---|---|
| Format: | Article |
| Language: | zho |
| Published: |
Surveying and Mapping Press
2017-09-01
|
| Series: | Acta Geodaetica et Cartographica Sinica |
| Subjects: | |
| Online Access: | http://html.rhhz.net/CHXB/html/2017-9-1165.htm |
| Summary: | Due to the noise sensitivity and limited directivity of extracted edge presented in current edge detection algorithms, it is difficult to effectively extract the edges with any direction between the two regions with similar intensities from SAR images. In this paper, an edge extraction algorithm of SAR image using two symmetric windows is proposed. The position of grid point of any pixel in SAR image is employed as a symmetric center, then symmetric windows in any direction are constructed by the symmetric center. The kernel function of distances from the central pixel to pixels in each window is defined, then the weighted averages of pixel spectral measurements are calculated for the two symmetric windows, respectively. The absolute value of difference between above averages is employed as edge degree of the central pixel on this direction, and maximum degree from all directions is selected to judge the pixel as an edge pixel. To delete error edge pixels extracted, post-processing procedure based on filtering operation is designed. The interferences of speckle noises are overcome to some extent and edges in random direction are extracted accurately by the proposed algorithm, respectively, which is shown by qualitative and quantitative analysis of the edge extraction results from analog images. |
|---|---|
| ISSN: | 1001-1595 1001-1595 |