Checkerboard angular point automatic extraction method, system and device and medium

Abstract

The invention provides a checkerboard angular point automatic extraction method, system and device and a medium. The checkerboard angular point automatic extraction method comprises the following steps that a checkerboard image is obtained, binarization processing is conducted on the checkerboard image, a checkerboard binarization image is generated, and a plurality of contours are extracted from the checkerboard binarization image; grid contours are screened out from the multiple contours, and then the center point of each grid contour is determined; according to the center points of the four adjacent grid contours, coarse angular points of each grid area are determined; and extracting a sub-pixel of each coarse corner point, and determining a target corner point of each grid region according to the sub-pixel of each coarse corner point. According to the invention, the plurality of contours are extracted from the checkerboard binary image, the lattice contours are screened out from the plurality of contours, and then the central point of each lattice contour is determined, so that the coarse angular point of each lattice area can be determined, and then the target angular point is determined, and therefore, the angular points of the checkerboard are automatically extracted, and the accuracy of the checkerboard angular point extraction is improved. And the number of the checkerboards in the checkerboards does not need to be known.

Description

technical field [0001] The present invention relates to camera calibration, in particular to a method, system, device and medium for automatically extracting checkerboard corner points. Background technique [0002] In the image measurement process and machine vision applications, in order to determine the relationship between the three-dimensional geometric position of a point on the surface of a space object and its corresponding point in the image, it is necessary to establish a geometric model of camera imaging, and these geometric model parameters are camera parameters. Under most conditions, these parameters must be obtained through experiments and calculations. This process of solving parameters is called camera calibration. [0003] When the camera is calibrated, a calibration plate is usually used for calibration. The geometric model of the camera can be obtained by shooting the flat plate with a fixed-pitch pattern array by the camera and calculating the calibrati...

AI Technical Summary

Problems solved by technology

However, when the checkerboard image fills the entire camera field of view, errors often occur when identifying corner points at this time, so that it is impossible to label each grid area in the checkerboard image

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