Polarimetric SAR speckle noise suppression method based on non-local bilateral filtering

Abstract

The invention discloses a polarimetric SAR speckle noise suppression method based on non-local bilateral filtering. The method mainly solves the problem of loss of edge texture details in the prior art. The method comprises the steps of 1, searching for similar pixel points of a polarimetric SAR image to form a similar pixel point set and obtain the similarity weight; 2, obtaining neighborhood windows with similar pixel points as the centers and carrying out bilateral filtering on the neighborhood windows to obtain filtering results; 3, carrying out non-local weight averaging on all the filtering results of the similar pixel points to obtain a covariance matrix generated after primary filtering; 4, filtering the covariance matrix generated after primary filtering to obtain a covariance matrix generated after final filtering; 5, synthesizing the covariance matrix generated after final filtering into a pseudocolor image and converting the pseudocolor image into a grayscale image. According to the method, information of the edge texture details can be kept on the premise that speckles are suppressed, and therefore the effect of suppressing the speckles of the polarimetric SAR image is improved. The method can be used for terrain classification and target identification of the polarimetric SAR image.

Description

technical field [0001] The invention belongs to the technical field of image data processing, and in particular relates to a method for suppressing coherent spots, which can be used for denoising polarimetric synthetic aperture radar SAR image data, and improves the subsequent image interpretation capability. Background technique [0002] With the development of radar technology, polarization SAR has become the development trend of SAR. Polarization SAR can obtain more abundant target information, and can reflect the advantages of polarization SAR system in terms of improving target detection, discrimination and classification capabilities. However, like SAR images, coherence speckles inevitably appear in polarimetric SAR images, which directly affects the extraction and interpretation of data information. Therefore, the suppression of coherent speckle noise has become the primary problem of polarimetric SAR data information processing, and it is also one of the hot spots of...

AI Technical Summary

Problems solved by technology

However, due to the selection of parameters, there are contradictions in retaining details, point targets and maximum noise suppression. For example, when the neighborhood window is too large, noise can be better suppressed, but point targets and details may be lost; neighborhood window selection If the value is too small, the point target and details can be well preserved, but the noise suppression ability is relatively weakened

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