Self-calibration of the distortion of a zooming camera by matching points at different resolutions

This paper presents a new method for the self-calibration of the lens distortion of a zooming camera, which appears for short focal lengths. The proposed technique does not need any special calibration pattern nor any prior knowledge about the environment. The key idea is to match points between a distorted image and an undistorted image taken at different resolutions. A new method for automatically matching points in the two images is proposed. The scale factor between the images is not needed for the matching algorithm. Matched points are used to compute invariants to the pinhole camera parameters. Then, lens distortion parameters are estimated in order to obtain the same invariants in both images. This approach is well suited to autonomous robotic vision applications. In fact, the self-calibration of the camera is done before moving the robot. Experiment with ground truth and tests on real images provide good results.

[1]  Jean-Marc Lavest,et al.  Some Aspects of Zoom Lens Camera Calibration , 1996, IEEE Trans. Pattern Anal. Mach. Intell..

[2]  Cordelia Schmid,et al.  Local Grayvalue Invariants for Image Retrieval , 1997, IEEE Trans. Pattern Anal. Mach. Intell..

[3]  Ezio Malis,et al.  An Unified Approach to Model-Based and Model-Free Visual Servoing , 2002, ECCV.

[4]  Roger Y. Tsai,et al.  A versatile camera calibration technique for high-accuracy 3D machine vision metrology using off-the-shelf TV cameras and lenses , 1987, IEEE J. Robotics Autom..

[5]  G. F. McLean,et al.  Line-Based Correction of Radial Lens Distortion , 1997, CVGIP Graph. Model. Image Process..

[6]  Gideon P. Stein,et al.  Lens distortion calibration using point correspondences , 1997, Proceedings of IEEE Computer Society Conference on Computer Vision and Pattern Recognition.

[7]  Christopher G. Harris,et al.  A Combined Corner and Edge Detector , 1988, Alvey Vision Conference.

[8]  Olivier D. Faugeras,et al.  Automatic calibration and removal of distortion from scenes of structured environments , 1995, Optics & Photonics.

[9]  Rachid Deriche,et al.  A Robust Technique for Matching two Uncalibrated Images Through the Recovery of the Unknown Epipolar Geometry , 1995, Artif. Intell..

[10]  Paul R. Cohen,et al.  Camera Calibration with Distortion Models and Accuracy Evaluation , 1992, IEEE Trans. Pattern Anal. Mach. Intell..