Camera calibration checkerboard image corner detection method based on symmetry analysis

Abstract

The invention discloses a camera calibration checkerboard image corner detection method based on symmetry analysis. The method comprises the steps that firstly, an input road image is preprocessed; then, candidate feature points are extracted from a checkerboard image according to the characteristic that checkerboard corners have the structural symmetry, and image feature points are detected through candidate feature point clusters and ChESS operators; finally, according to the characteristic that the corners of the checkerboard image exist in the image feature points and have the structural symmetry, detection of all the corners of the checkerboard image is achieved by calculating the initial corner first and then calculating the positions of the other corners. According to the method, the symmetry of the checkerboard image is comprehensively considered, and automatic detection of the corners of the checkerboard image is achieved. The method has great significance for automatic camera calibration. Due to the fact that background feature points and the corners of the checkerboard image can be effectively distinguished, the method has high robustness.

Description

technical field [0001] The invention relates to the fields of image processing and machine vision, in particular to a camera calibration checkerboard image corner point detection method based on symmetry analysis in the field of image processing and machine vision. Background technique [0002] In the field of image measurement and machine vision, camera calibration refers to the process of obtaining the internal and external parameters of the camera according to the camera model. It is the basic step to obtain 3D information from 2D images. Among the existing camera calibration methods, the plane template calibration method based on the black and white chessboard image is widely used because the calibration template is easy to make and the calibration method is mature. Since the camera calibration accuracy largely depends on the positioning accuracy of the corner points of the calibration template, how to detect the corner position of the calibration template is an importan...

AI Technical Summary

Problems solved by technology

In general, compared with the camera calibration method, there are still few methods currently proposed for automatic detection and extraction of checkerboard image corners, which hinders the improvement of the automation of the camera calibration process to a certain extent.

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