Heterogeneity pre-correction-based wavelet domain SAR image despeckling method

Abstract

Provided is a heterogeneity precorrection-based wavelet domain SAR image despeckling method. In a wavelet domain, statistics of SAR image local heterogeneity is carried out, heterogeneity information and a precorrection function are combined, and a homogeneous area is smoothed before image despeckling, thereby protecting texture information of the homogeneous area and improving the over-smoothing problem which may occur in the image despeckling process. With a simple process, the method of the invention achieves a good image despeckling effect and low computation complexity of a pre-correction algorithm, and solves the problems of conventional SAR image despeckling methods, such as low pertinence of image signal processing, insensitivity to noise, low anti-interference ability, failure of detailed reflection of the subtle difference among sub blocks, poor image despeckling effect, complex computation, complicated process and the like.

Description

Technical field: [0001] The invention relates to a wavelet domain SAR image speckle removal method based on heterogeneity pre-correction, and belongs to the technical field of SAR image processing. Background technique: [0002] Synthetic aperture radar (SAR) is regarded as a new generation of remote sensing information source because of its all-time, all-weather, multi-polarization, multi-angle data acquisition capabilities and good penetration performance. However, since the SAR system uses coherent waves for imaging, the coherent speckle noise seriously reduces the interpretability of SAR images and affects the applications of target detection, classification, recognition and information extraction. Therefore, it is necessary to study the method of coherent speckle suppression in SAR images. [0003] With the application of wavelet tools in SAR image processing, wavelet-based speckle removal methods have become an important branch of SAR image speckle removal methods. Am...

AI Technical Summary

Problems solved by technology

In the wavelet domain, by counting the local heterogeneity of the SAR image, the heterogeneity information is combined with the pre-correction function to smooth the homogeneous area before image despeckling, protect the texture information of the heterogeneous area, and improve the image over-smoothing in the process of despeckling The problem of this method is that the speckle removal effect is good, the calculation complexity of the pre-correction algorithm is low, and the process is simple, which solves the problem that the SAR image speckle removal method in the prior art has weak pertinence for image signal processing, is not sensitive to noise, and has good anti-interference ability. Weak, it cannot reflect the subtle differences between sub-blocks in detail, the effect of image despotting is not good, the calculation is complicated, the process is cumbersome, etc.

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