Unsupervised change detection method and device based on full polarization sequential SAR image

Abstract

The invention relates to an unsupervised change detection device based on a full polarization sequential SAR image; the device comprises the following units: an image preprocessing unit used for registering and filtering a pair of full polarization sequential SAR images of different time phases in a same geological scope; a preliminary difference image forming unit used for carrying out hypothesis examination for corresponding positions in the pair of full polarization sequential SAR images, thus forming a preliminary difference image; an optimal threshold select unit using a KI algorithm to select the optimal threshold of the formed preliminary difference image; a detection result forming unit using the selected optimal threshold to carry out binary segmentation for the preliminary difference image, endowing values representing no changes for pixels smaller than the threshold, endowing values representing changes for pixels bigger than the threshold, and finally forming the detection result. The method and device can fully utilize the SAR image full polarization information, thus automatically extracting change information of SAR images of different time phases with high precision.

Description

technical field [0001] The invention belongs to the technical field of remote sensing image processing, and relates to a method for non-supervised change detection of time-series images, in particular to using the hypothesis test of the Wishart distribution conforming to full polarization information and the KI minimum classification error method to detect time-series synthetic aperture radar (Synthetic Aperture Radar) A method and system for unsupervised change detection on Aperture Radar (SAR) images. Background technique [0002] Synthetic Aperture Radar (SAR) technology is an important means of earth observation. Compared with optical remote sensing technology, Synthetic Aperture Radar (SAR) system has the advantage of all-weather and all-weather acquisition of remote sensing data. . At the same time, SAR is also very sensitive to the geometric and physical characteristics of the detection target, and is a good source of change detection information. Therefore, it is wi...

AI Technical Summary

Problems solved by technology

However, existing change detection algorithms have problems such as insufficient utilization of polarization information and the need for manual intervention.

[0004] Moreover, in a complex geographical environment, the backscattering characteristics of ground objects are easily affected by many factors: such as the biology of ground objects, physical parameters, dielectric constant, environmental factors (such as weather conditions), radar parameters (radar wave Incidence angle, wavelength, polarization mode), etc., so even for unchanged ground objects, there are different degrees of differences in the gray value and statistical characteristics of SAR images in different phases. Complexity and Difficulty of Change Detection Techniques

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