APPARATUS AND METHOD FOR ESTIMATING CAMERA FOCAL LENGTH

摘要

An apparatus and a method for estimating a focus length of a camera are provided to calculate the fixed focus length of a zoom lens camera from the positions of the corresponding points between images and to verify the reliability of the calculated focus length easily. An image corresponding point position designation member(110) designates the corresponding point positions between the inputted two dimensional image pair. A cost function defining member(120) defines a cost function in order to calculate the focus length for performing the automatic correction of a camera from the corresponding point positions between the designated image pair. A cost function minimizing member(130) calculates the optimum focus length for minimizing the defined cost function. A position and posture calculating member calculates the photographing position and posture of a camera through an algorithm including 5-points, 6-points, 7-points and 8-points by means of the focus length and the corresponding point positions between image pair.