A high-precision binocular camera calibration method

Abstract

The invention discloses a high-precision binocular camera calibration method. The calibration method is completed by using a pair of camera equipment and a calibration plate of a circular characteristic image. First, the image coordinates of the control points in the calibration plate are extracted for initial camera calibration; Construct the front-view image of the calibration board with parameters, use the digital image correlation method to obtain the image coordinates of the control points in the front-view image, correct the image coordinates in the calibration board, and perform camera calibration again; finally, establish the overall optimization model of the binocular camera according to the fixed position relationship between the cameras. Optimize camera parameters. According to the calibration method of the present invention, the coordinates of the control points in the calibration plate are accurately obtained, the optimization model of the calibration parameters of the stereo camera is simplified, and high-precision calibration results can be obtained.

Description

technical field [0001] The invention belongs to the technical field of machine vision calibration, and relates to a binocular camera calibration method based on a circular calibration board and image processing technology. Background technique [0002] In the binocular camera calibration work using a circular calibration plate, the extraction accuracy of the control point position and the selection of the optimal objective function will have an important impact on the calibration accuracy. And when the camera captures the image of the calibration plate, since the camera imaging plane and the plane of the calibration plate usually do not maintain a parallel spatial relationship, the circular pattern will be affected by the perspective transformation during the imaging process and will be deformed. [0003] Camera calibration is based on the nonlinear distortion model of camera imaging, using Zhang's camera calibration method to calibrate the internal and external parameters o...

AI Technical Summary

Problems solved by technology

[0016] The purpose of the present invention is to provide a high-precision binocular camera calibration method, which uses a circular calibration plate to solve the problem of control point positioning error caused by the ellipse fitting method in the prior art, and improves the extraction of control point coordinates Accuracy, using the integrity of the binocular camera model to establish a simple optimization objective function to achieve high-precision calibration of the binocular camera

Images