Monocular camera rapid calibration method based on coding three-dimensional target

Abstract

The invention discloses a monocular camera rapid calibration method based on a coding three-dimensional target, and the method comprises the steps: shooting a coding three-dimensional target in a space through employing a camera with a fixed position in the space, and obtaining a target image; through a decoding method of the coding three-dimensional target, obtaining a sub-pixel coordinate of a calibration corner point, a unique coding sequence number of the calibration corner point and a world coordinate of each coding plane target on the coding three-dimensional target in a target image, and if the target image meets a calibration condition, taking the target image as a calibration image; and finally, solving internal and external parameters of the camera by using a calibration algorithm according to the calibration image. According to the invention, automatic calibration of the internal and external parameters of the monocular camera can be realized, calibration work can be completed by using a plurality of complete or local coding plane target images contained in one target image, the complexity of camera calibration is reduced, and the efficiency of camera calibration is improved.

Description

technical field [0001] The invention relates to the field of camera calibration methods in computer vision, in particular to a fast calibration method for monocular cameras based on encoded stereo targets. Background technique [0002] Computer vision technology is widely used in industrial control, metrology and other fields. Computer vision technology mainly uses camera imaging to obtain three-dimensional information of the measured object in space through image information, thereby reconstructing and identifying the object. The fundamental problem of computer vision technology is camera calibration. The mapping relationship between three-dimensional coordinates of space and two-dimensional coordinates of images can be obtained through camera calibration technology. Camera calibration technology is the research focus of computer vision measurement technology. The task of camera calibration is to solve the Internal and external parameters, camera calibration technology has ...

AI Technical Summary

Problems solved by technology

[0003] In 1986, Roger Tsai proposed a camera calibration algorithm based on radial constraints, which required a 3D stereo target, making the calibration process inflexible; around 1999, Zhang Zhengyou (Z.Y Zhang) proposed a camera calibration algorithm based on a plane target, which The calibration algorithm uses a plane target that does not contain direction information and coding information. During the calibration process, the rotation direction of the plane target without direction information cannot be judged, and the camera calibration algorithm based on the plane target proposed by Z.Y Zhang requires the camera to capture A complete planar target, but the camera often fails to capture a complete planar target during the actual calibration process. At this time, it is difficult to perform camera calibration and ensure camera calibration accuracy using traditional planar targets that do not contain direction information and encoding information.

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