Wavelet-decomposition-based SAR image change detecting algorithm of multi-scale level set

Abstract

The invention discloses a wavelet-decomposition-based SAR image change detecting algorithm of a multi-scale level set, and belongs to the field of remote sensing image processing. The wavelet-decomposition-based SAR image change detecting algorithm mainly solves the problem that a speckle noise effect is serious in an SAR image change detecting process. The wavelet-decomposition-based SAR image change detecting algorithm is implemented in the following steps that (1) a difference image of two registered SAR images in the same region and at different time phases is obtained by adopting logarithm ratio operators; (2) multilayer wavelet decomposition is conducted on the difference image through SWT so as to obtain images with different resolution ratios; (3) the images with the low resolution ratios are preliminarily segmented through a level set algorithm, and the outlines of obtained segmented images are used as initialization curves of the level set algorithm of the images with the higher resolution ratios; (4) the step (3) is repeated in a layer-by-layer mode until final segmented images are obtained by conducting level set segmentation on the images with the high resolution ratios. According to the wavelet-decomposition-based SAR image change detecting algorithm, the multi-scale application overcomes the defect that a closed curve is prone to getting into local optimum in a level set evolutionary process, and robustness on noise is enhanced; the wavelet-decomposition-based SAR image change detecting algorithm is applied to change detecting of the SAR images, the detecting effect and detecting accuracy are improved obviously, and the change detecting process is accelerated.

Description

technical field [0001] The invention belongs to the field of remote sensing image processing, relates to change detection of remote sensing images, and specifically provides a SAR image change detection method based on wavelet decomposition multi-scale level set, which can be used to detect SAR image changes. Background technique [0002] Compared with visible light and infrared sensors, synthetic aperture radar (SAR) has the characteristics of high resolution, all-day and all-weather work, and is a better image source for change detection. Remote sensing image change detection is to compare and analyze two remote sensing images obtained at different times in the same area, and extract ground object changes and target change information according to the differences between the obtained images. With the development of remote sensing technology, the technical demand for SAR image change detection is becoming more and more extensive. At present, global environmental changes are...

AI Technical Summary

Problems solved by technology

This method is a relatively intuitive method, and its advantage is that it can avoid the radiation normalization problem caused by different environmental conditions and different sensors for multi-temporal remote sensing image data, and can directly obtain the type, quantity, and position of changes.

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