Camera Calibration with Conics Fitting and
Circular Points
Hu Zhaozheng£¬Tan Zheng
£¨School of Electronics and Information Engineering£¬Xi'an¡¡Jiaotong¡¡University£¬Xi'an
710049£¬China£©
Abstract£ºTo improve the accuracy and practicality of camera calibration£¬ a novel
algorithm is proposed by using a new calibration model which consists of two planar
intersection circles. The radii and the centers of the circles are both unknown. The
algorithm uses conics fitting to calculate the images of the circular points from the
images of the circles. Compared with the plane based algorithm£¬ it can avoid the corner
extraction and correspondence problems£¬and automatic calibration can be carried out
easily without human interference. Besides£¬ it uses more image points for calibration.
The simulation results show that the relative error for the focal length is reduced by 0.1£¥
compared to that of the plane based algorithm under the realistic noise level £¨0.5 pixel£©.
And the relative error for the principal point is a little smaller as well. The results
with real image data also demonstrate that the proposed algorithm is accurate and
practical.
Keywords£ºcamera calibration£» conics fitting£» circular points£» calibration pattern