Patent ID: 7155030
Filing Date: 2006-12-26
Classification: G06T,H04N

Abstract:
1. A method of calibrating a camera using projection invariable characteristic of a concentric circle in order to calibrate the camera through a calculation of camera's intrinsic parameters, the method comprises steps of: a) taking a plurality of images of a calibration pattern consisting of two or more concentric circles located at a same plane and having different radiuses at different angles to obtain projected images resulted from the projection of the concentric circles; b) calculating central points of the projected images using a given algorithm; and c) calculating an optimum principal point (u wherein the concentric circle includes two circles and the step b) includes the steps of: d) calculating the central points (O) of the two projected images obtained from the step a) to obtain a straight line passing through the central points; e) calculating crossing points of the straight line and the two projected images; and f) calculating the central point of the projected images using a cross ratio depending on the central point (O) of the projected images, a given point (M