A new sub-pixel detector for grid target points in camera calibration

D. Chen; Y. Wang; G. Zhang

doi:10.1117/12.668295

20 January 2006 A new sub-pixel detector for grid target points in camera calibration

D. Chen, Y. Wang, G. Zhang

Proceedings Volume 6027, ICO20: Optical Information Processing; 60272N (2006) https://doi.org/10.1117/12.668295
Event: ICO20:Optical Devices and Instruments, 2005, Changchun, China

Abstract

Sub-pixel detection of target points is an important task in camera calibration. Grid target points are widely used in camera calibration for their junctions can be easily detected. Traditional method detects the sub-pixel position of grid-point by calculating the intersection of two beelines fitted by centers of grid-lines. Generally, this method yields low precision because of the effect of projective distortion of camera lens. In this paper, we propose a new sub-pixel detector for grid target points. We firstly use a new shape operator based on Hessian matrix to detect the pixel position of grid-point. Then the intensity of sub-pixel points in the neighborhood of grid point is calculated by cubic interpolation. A minimum restriction for searching grid-point is deduced by the fact that the grid-point to be detected is just the extremal point of local intensity profile. According to this restriction, the sub-pixel position of grid-point is finally determined by a graded morphological shrinking operation. Computer simulation results indicate that our new algorithm is more accurate and robust than the traditional algorithm.

Citation Download Citation

D. Chen, Y. Wang, and G. Zhang "A new sub-pixel detector for grid target points in camera calibration", Proc. SPIE 6027, ICO20: Optical Information Processing, 60272N (20 January 2006); https://doi.org/10.1117/12.668295

ACCESS THE FULL ARTICLE

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available