SAR image splicing method based on sub-block registration

Abstract

The invention discloses an image splicing technology based on sub-block registration, which realizes quick and accurate splicing of adjacent SAR images and solves the problem of poor conventional splicing effect caused by spatial variation of the SAR images in distance. T he distance direction and the azimuth direction of the SAR image are respectively segmented, the coordinates of the feature points of the image overlapping region are extracted, and the feature points of the whole image are prevented from being searched and matched by utilizing the characteristic that the overlapping degree of the adjacent distance blocks is high, so that the SAR image splicing becomes simple and efficient; through multiple times of iterative registration, the registration degree of the reference image and the re-sampled to-be-registered image becomes higher and higher, and by means of weighted splicing, the splicing positions of the images are fused naturally without splicing traces.

Description

technical field [0001] The invention belongs to the technical field of radar imaging, and in particular relates to a SAR image splicing method. Background technique [0002] Synthetic aperture radar (SAR) has the characteristics of all-day, all-weather, high resolution, strong penetrating power, etc. important means. [0003] Due to hardware and algorithm limitations, synthetic aperture radar imaging cannot be infinitely extended in azimuth. It can only process long-distance flight echoes in segments to form multiple sub-images that are updated sequentially in azimuth scenes. At the same time, factors such as aircraft jitter and airflow are still Will result in a small rotation between two adjacent images. [0004] In order to observe the continuous area, part of the echo data will be processed twice by the imaging algorithm. This processing method will cause a certain overlapping area between two adjacent images. In order to obtain continuous images of large scenes, it is...

AI Technical Summary

Problems solved by technology

[0005] There are errors in the sensor characteristics and signal processing process of obtaining different SAR images. Affected by these factors, the grayscale of the radar image will be different. Even in the overlapping area of ​​two adjacent SAR images, there will be a difference in grayscale. , resulting in gray discontinuity at the splicing point, because there is an offset problem between the SAR images, so the direct splicing method cannot be used

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