Registering method for optical and radar images

Abstract

Disclosed is a registering method for optical and radar images: (1) a radar image is used as a reference image and an optical image is used as a to-be-registered image and downsampling is performed on the reference image and the to-be-registered image respectively so that images of no less than three layers and different resolutions are generated; (2) starting from the image of the first layer and low resolution, image transformation is performed on the image of each layer through use of mutual negative information values; (3) characteristic point sets of coordinates at which gradient magnitudes in the optical and the radar images exceed the gradient magnitude of a preset threshold value, are extracted respectively; (4) translational transformation parameters used in transformation of the image of the last layer in step (2) are used to transfer optical-image coordinate characteristic point sets extracted in the step (3) to radar-image coordinate characteristic point sets; (5) within the range of the transferred point sets, a target function is optimized and a translational transformation parameter corresponding to the maximum of the target function is selected as a fine registration parameter; (6) the fine registration parameter is used to perform transformation and resampling on the to-be-registered image so that a registered image is obtained.

Description

technical field [0001] The invention relates to a processing method for optical and radar image registration. Background technique [0002] Remote sensing technology has now been transferred to practical applications at the social and scientific level, including natural disaster management, climate change assessment, natural resource management, environmental protection, etc., all of which involve long-term monitoring of the earth's surface. In recent years, image registration has become very important in remote sensing applications. Image registration is a basic task in image processing, which refers to matching two or more images of the same object or scene from different times, different remote sensors, and different perspectives. Image registration is used in digital image processing to accurately align two or more digital images for analysis and comparison, involving knowledge in many fields such as physiology, computer vision, pattern recognition, and image understand...

AI Technical Summary

Problems solved by technology

[0004] The problem solved by the technology of the present invention is: due to the different imaging principles of different sensors, there are large grayscale differences between the obtained images (such as optical images and radar images), and the features of the same scene in different types of images are also different. Common features are difficult to extract, which makes various registration methods based on grayscale correlation and image features no longer applicable and the effect is not good. Therefore, this technology will propose a new method to solve the above problems and apply it to the registration of optical and radar images

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