Sequential SAR space-time neighborhood gauss weighting median filtering speckle noise suppression rapid algorithm

Abstract

The invention discloses a sequential Synthetic Aperture Radar (SAR) space-time neighborhood gauss weighting median filtering speckle noise suppression rapid algorithm, and provides a median filtering algorithm which performs gauss weighting according to time and space distance based on the condition that observation values of different time sequential SAR images are highly correlated with the observation values of a time neighborhood and a space neighborhood at the same time, and the larger the time interval is and the larger the space distance is, the less the correlation is. A section where the median is is pre-estimated according to statistic distribution characteristics of the SAR images, a median searching scope is reduced, and a median solving speed is accelerated. According to the invention, natural object features on the images can be kept well, and the speckle noise is suppressed. Meanwhile the influence of temporary natural objects such as vehicles and boats in the sequential images can be removed to a larger extent, and the sequential image speckle noise suppression problem is solved.

Description

【Technical field】 [0001] The invention belongs to the technical field of remote sensing image processing, is a synthetic aperture radar (Synthetic ApertureRadar, SAR) image coherent speckle noise suppression method, and relates to a new method for filtering coherent speckle noise in heavy-track time series SAR images, Specifically, it relates to a fast algorithm of Gaussian weighted median filter in time-series SAR images for speckle noise suppression. 【Background technique】 [0002] Synthetic aperture radar is not limited by factors such as weather, geography and time. It can perform high-resolution imaging on the ground and has certain penetrating power. Therefore, it is widely used in military reconnaissance, resource detection, environmental monitoring, surveying and mapping, and geographical conditions. In ground remote sensing applications such as monitoring, with the successful launch of multiple radar satellites, time-series radar images have become an important aspe...

AI Technical Summary

Problems solved by technology

[0006] The present invention is a time-series SAR space-time neighborhood Gaussian weighted median filter speckle noise suppression fast algorithm, which makes full use of the correlation between the time-neighborhood and spatial-neighborhood observation values ​​in the SAR time-series image, and utilizes the median filter algorithm to suppress speckle noise and other non-spot noises. Good performance of Gaussian noise suppression and detail information preservation. While suppressing speckle noise, it also suppresses the influence of temporary objects in time-series images, effectively solving the problem that existing methods fail to solve the problem of fast filtering of speckle noise in time-series SAR images.

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