SAR image speckle reduction method based on directional wave domain HMT model

Abstract

The invention discloses an SAR image speckle reduction method based on a directional wave domain HMT model, which is mainly used for solving the problem that detail information such as the edge structure of the image cannot be effectively kept and the radiation characteristic of an SAR image cannot be kept well in the existing method. The SAR image speckle reduction method comprises the following realization steps of: (1) inputting an image; (2) establishing a non-logarithm additive model; (3) constructing a directional wave domain HMT model parameter set; (4) establishing the directional wave domain HMT model parameter set; (5) estimating the directional wave high-frequency sub-band coefficient of a spotless image; (6) carrying out directional wave inverse transformation; (7) outputting the estimated spotless image. The SAR image speckle reduction method disclosed by the invention has the advantages of being capable of effectively keeping the edge and detail information of the image, and more obvious in speckle reduction effect, and can be used for speckle reduction processing for the SAR image.

Description

technical field [0001] The present invention belongs to the technical field of image processing, and further relates to a synthetic aperture radar (Synthetic Aperture Radar, SAR) model based on a directional wave domain hidden Markov tree (Hidden Markov tree, HMT) model in the technical field of synthetic aperture radar image speckle reduction. ) image speckle reduction method. The invention can be used for speckle reduction processing on SAR images. Background technique [0002] The existence of coherent speckle noise in SAR images seriously affects the perception of SAR images by human vision, and restricts the application of SAR images in image segmentation and change detection. Therefore, effective denoising of SAR images is one of the SAR image processing Urgent needs. [0003] Xidian University proposed a SAR image based on SWT domain improved particle filter in its patent application "SAR image speckle reduction method based on SWT domain improved particle filter" (...

AI Technical Summary

Problems solved by technology

Although this method utilizes the inter-scale, intra-scale and intra-direction correlations of the contourlet coefficients, overcomes the pseudo-Gibbs phenomenon caused by the non-translation invariance of the contourlet transformation, and improves the equivalent visual number of the homogeneous area, but still The disadvantage is that the conversion of coherent speckle noise into additive noise through logarithmic operation cannot well maintain the radiation characteristics of SAR images, resulting in the inability to completely remove coherent speckle noise in subsequent processing

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