An Image Registration Method for Acoustic Vision 3D Imaging of Underwater Robots

Abstract

The invention relates to the field of sonar image processing, in particular to an image registration method of acoustic and visual three-dimensional imaging with an underwater vehicle, which overcomes target sonar image rotation due to swing of the underwater vehicle, and eliminates adverse effects of three-dimensional reconstruction distortion. The method comprises the following steps of (1), detecting a rotation angle of a target image, (2), correcting rotation of the target image, and (3), reconstructing a corrected image sequence. The method can correct sonar image sequences in a self-adapting manner without any prior knowledge to allow the sonar image sequences to be aligned axially, overcomes the defect that a reference image is required in the traditional registration method, is a quick automatic registration method, and is small in computation amount.

Description

technical field [0001] The invention relates to the field of sonar image processing, in particular to a method for registering an underwater robot's acoustic vision three-dimensional imaging image to overcome the rotation of a target sonar image caused by the swing of an underwater robot and eliminate the adverse effects of three-dimensional reconstruction distortion. Background technique [0002] In recent years, imaging sonar has received extensive attention and development in the field of underwater acoustics. Among them, 3D imaging sonar can still obtain detailed information and environmental information of the outline of underwater targets under turbid water quality and poor lighting conditions. With the help of computer visualization technology, these information can be displayed in the form of vivid three-dimensional graphics and images, and can be observed and analyzed from various perspectives through operations such as zooming, moving, rotating and ranging, so as to...

AI Technical Summary

Problems solved by technology

[0005] The underwater robot relies on the propeller to control its movement in the water, but due to its nonlinear hydrodynamic characteristics, the random disturbance of the water flow and the differential feedback control mechanism and other factors, it will swing from side to side during the dive process.

The image sonar rigidly connected to the robot also sways left and right, and the target image it collects rotates around the center of the sonar, causing the images of each frame to not be axially aligned, and the 3D reconstructed image will appear distorted

The existing image registration technology is mainly used in the field of medical images, mainly based on phase correlation technology, but phase correlation technology requires all or part of the information of the original image or reference image, which limits the application

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