Coherent Speckle Filtering Method for Single Polarization SAR Image Combined with Context Covariance Matrix

Abstract

The invention discloses a single-polarization SAR image coherent speckle filtering method combined with a context covariance matrix, including 1. Inputting a single-polarization SAR image to be filtered; 2. For pixels in the single-polarization SAR image, Construct the context scattering vector in the neighborhood, and construct the context covariance matrix; 3. Obtain the similarity parameter; 4. Calculate the judgment threshold of the similarity parameter; 5. Select similar sample pixel sets, and perform filtering processing on the pixels to be filtered; steps 6: Iterate over each pixel in the single-polarization SAR image to be filtered, and repeat steps 2 to 5 to obtain a filtering result map. The present invention effectively utilizes the context information of each pixel by constructing the context covariance matrix, calculates the similarity by calculating the context covariance matrix of each pixel and the pixels in its neighborhood, and improves the selection accuracy of similar pixels. Therefore, similar pixels The similarity of the sample set is higher, so that the coherent speckle filter is performed on the image, and the filter performance is superior.

Description

technical field [0001] The invention belongs to the technical field of SAR (Synthetic Aperture Radar, synthetic aperture radar) imaging remote sensing, and relates to a single-polarization SAR image coherent speckle filtering method combined with a context covariance matrix. Background technique [0002] Coherence speckles widely exist in the images obtained by coherent imaging systems such as SAR. The existence of coherence speckles brings difficulties and challenges to the understanding and interpretation of SAR images. When processing such as target detection, classification and recognition, it is usually necessary to preprocess the SAR image with speckle filtering. Speckle filtering methods with excellent performance require that the details of ground objects should be well preserved while fully suppressing speckle. As a SAR image preprocessing, the performance of speckle filtering directly affects the effects of various subsequent processing and applications. Therefo...

AI Technical Summary

Problems solved by technology

In the process of selecting similar samples, the above methods mainly use the amplitude information of each pixel or the pixels in each small block, and do not fully consider the context information of the pixel point and the surrounding adjacent pixels, and there are deficiencies in the number and accuracy of similar sample selection. , resulting in insufficient speckle filtering performance

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