WIDE ANGLE IMAGE DISTORTION CORRECTION BASED ON THE DOUBLE CHORDS PLUMBLINES METHOD

The calibration correction algorithm for distorted images requires the use of a calibration plate, which cannot correct images taken with a wide-angle lens in real-time. To address this problem, a distortion correction algorithm based on the double-chord plumb line is proposed. The concept of distortion line was introduced and the extreme aberration line was processed through thresholding. The center of the contour circle was obtained by using the intersection of the double-chord plumb line at the beginning and end points of the distorted line, and the distortion parameters were obtained by combining the equations of the contour circle. The reverse mapping was used to complete the distortion correction. The experimental analysis gives the subjective visual effect of the corrected images as well as the evaluation indexes NIQE value and image entropy value, verifying the good correction ability of the correction algorithm for distorted images without loss of image information; and verifying the optimization effect of the algorithm on the longitude correction algorithm for fisheye images in conjunction with the variation SSIM values.