Camera calibration using two concentric circles: linear approach

In several machine vision applications, a fundamental step is to precisely determine the relation between the image of the object and its physical dimension by performing a calibration process. The aim is to devise an enhanced mechanism for camera calibration in order to improve the already existing methods in OpenCV. A good calibration is important when we need to reconstruct a world model or interact with the world as in case of robot, hand-eye coordination. In order to meet the rising demands for higher accuracy various calibration techniques have been developed but they are unable in obtaining precise results. In this paper we propose an enhanced camera calibration procedure using a special grid pattern of concentric circles with special markers. The overall objective is to minimize the re-projection for good camera calibration.

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Line-scan camera calibration: a robust linear approach

Applied Optics ◽

10.1364/ao.404774 ◽

2020 ◽

Vol 59 (30) ◽

pp. 9443

Author(s):

R. Usamentiaga ◽

D. F. Garcia ◽

F. J. de la Calle

Keyword(s):

Camera Calibration ◽

Line Scan ◽

Linear Approach

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Geometric and algebraic constraints of projected concentric circles and their applications to camera calibration

IEEE Transactions on Pattern Analysis and Machine Intelligence ◽

10.1109/tpami.2005.80 ◽

2005 ◽

Vol 27 (4) ◽

pp. 637-642 ◽

Cited By ~ 122

Author(s):

Jun-Sik Kim ◽

P. Gurdjos ◽

In-So Kweon

Keyword(s):

Camera Calibration ◽

Concentric Circles ◽

Algebraic Constraints

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Using concentric circles and wedge grating for camera calibration

Applied Optics ◽

10.1364/ao.51.003811 ◽

2012 ◽

Vol 51 (17) ◽

pp. 3811 ◽

Cited By ~ 19

Author(s):

Junpeng Xue ◽

Xianyu Su ◽

Liqun Xiang ◽

Wenjing Chen

Keyword(s):

Camera Calibration ◽

Concentric Circles

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Method of Camera Calibration Using Concentric Circles and Lines through Their Centres

Advances in Multimedia ◽

10.1155/2018/6182953 ◽

2018 ◽

Vol 2018 ◽

pp. 1-8

Author(s):

Yue Zhao ◽

Xuechun Wang ◽

Fengli Yang

Keyword(s):

Camera Calibration ◽

Real World ◽

Cross Ratio ◽

Lens Distortion ◽

Vanishing Point ◽

Vanishing Points ◽

Novel Method ◽

Ideal Points ◽

Concentric Circles ◽

The Ideal

A novel method for camera calibration is proposed based on an analysis of lens distortion in camera imaging. In the method, a line through the centre of concentric circles is used as a template in which orthogonal directions can be determined from an angle of circumference that corresponds to a diameter. By using three lines through the centre of concentric circles, based on the invariance of the cross-ratio, an image at the centre of the concentric circles can be used to obtain the vanishing point. The intrinsic parameters of the camera can be computed based on the constraints of the orthogonal vanishing points and the imaged absolute conic. The lens distortion causes points in the template to have a position offset. In the proposed method, we optimize the positions of the distortion points such that they gradually approach those of the ideal points. The simulated and real-world experiments demonstrate that the proposed method is efficient and feasible.

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