SAR image speckle suppression method based on second generation curvilinear wave transformation

A coherent speckle suppression and curve wave technology, which is applied in image enhancement, image data processing, radio wave measurement system, etc., can solve the problems of image scratch effect, image edge blur, and curve wave transformation lack of translation invariance, etc. Detail information, the effect of removing the scratch effect

Active Publication Date: 2009-09-23
XIDIAN UNIV
View PDF0 Cites 17 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

The biggest shortcoming of this method lies in the "overkill" of the coefficients, which leads to the blurring of the edge of the image, and because the curvelet transform itself lacks translation invariance, the image after coherent speckle suppression has a scratch effect

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • SAR image speckle suppression method based on second generation curvilinear wave transformation
  • SAR image speckle suppression method based on second generation curvilinear wave transformation
  • SAR image speckle suppression method based on second generation curvilinear wave transformation

Examples

Experimental program
Comparison scheme
Effect test

Embodiment Construction

[0028] refer to figure 1 , the specific implementation steps of the present invention are as follows:

[0029] Step 1: Select the test SAR image I, and perform the second-generation curvelet transformation on it.

[0030] The present invention selects the mathematical model of testing SAR image as: y=x+n

[0031] Where y={y(i, j)|i, j=1, 2,...N} represents the SAR image, x={x(i, j)|i, j=1, 2,...N } represents the backscattering intensity of the real scene in the SAR image, n={n(i, j)|i, j=1, 2,...N} represents zero mean and variance equal to σ 2 Gaussian noise, N represents the size of the image;

[0032] Carry out the second-generation curvelet transform on the SAR image to be processed, divide it into five layers of subbands, and obtain the curvelet coefficient of the SAR image at the Wth subband position (i, j) of the S layer:

[0033] C(S,W,i,j)=s(S,W,i,j)+ε(S,W,i,j)

[0034] where s(S,W,i,j) and ε(S,W,i,j) are the backscattering intensity and noise curve wave coeffici...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

No PUM Login to view more

Abstract

The invention discloses an SAR image speckle suppression method based on second generation curvilinear wave transformation, which mainly overcomes the defect of scratch effect and point target loss brought by a curvilinear wave to the SAR image speckle suppression. The SAR image speckle suppression method comprises the following steps: performing the second generation curvilinear wave transformation to a selected test image and partitioning the selected test image into 5 layers of subbands; keeping coefficients of the first layer unchangeable and zero-setting coefficients of the fifth layer; respectively evaluating parameter vectors of hybrid Gaussian models from the second layer to the fourth layer by an EM method; marking the coefficients from the second layer to the fourth layer; reconstructing the image, detecting the edge of the reconstructed image, and performing the average filtering to the uniform area of the reconstructed image to obtain the filtered image; and performing the nonlinear anisotropy dispersion iteration to a difference image obtained by the original image and the filtered image to obtain a speckle suppressed image. The invention has the advantages of keeping clean edge of the image, removing the scratch effect and remaining the point target characteristic information of the image, and can be used for preprocessing scene analysis and image understanding in the SAR image.

Description

technical field [0001] The invention belongs to the field of digital image processing, and relates to a method for suppressing coherent spots of SAR images, which can be used for scene analysis and image understanding preprocessing in SAR images. Background technique [0002] SAR images have a very wide range of applications, but when SAR images are imaged, the scattered echoes of imaging scatterers have a coherent effect, making the images unable to effectively reflect the scattering characteristics of ground objects. This interference phenomenon is called speckle in SAR images. noise. The existence of speckle noise is very unfavorable to the analysis of the scene in the image and the understanding of the image, so the suppression of speckle noise is a very important part of SAR image processing. The main goal of suppressing speckle noise is to suppress speckle noise while maintaining details such as the edges of the image. [0003] SAR image coherence speckle suppression...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
Patent Type & Authority Applications(China)
IPC IPC(8): G06T5/00G01S7/48
Inventor 侯彪刘红华王爽焦李成张向荣马文萍
Owner XIDIAN UNIV
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap