Automatic lens distortion correction using single images by finding reliable lines for rectification

It is advantageous but difficult to automatically and accurately estimate parameters of lens models from single images, particularly in internet image processing and thermal image processing. As not all objects have straight edges, it is natural that some edges should be straight and some should be curved in undistorted images. Therefore, the key problem is how to find curved lines in original images that should be straight in undistorted images. In this paper, a novel algorithm is proposed to solve this key problem by automatically selecting reliable line segments for the estimation of lens model parameters. Experimental results show that the proposed algorithm is able to detect reliable lines and produce quality results for both indoor and outdoor images taken by different cameras using wide-angle and fisheye lenses as well as zoom lenses.