Patent ID: 6094504
Filing Date: 2000-07-25
Classification: H04N

Abstract:
A method for offsetting error resulting from displacement between a line segment and a line object, comprising the steps of:(a) determining compensation parameters by a calibration procedure;(b) performing a real-time position compensation method for offsetting said displacement error when positional coordinates of a pair of pointers is determinedwherein said calibration procedure comprises the steps of:(a) determining the positional coordinates of end points of said line object (C(X.sub.3, Y.sub.3) and D(X.sub.4, Y.sub.4);(b ) determining the positional coordinates of end points of said line object (A(X.sub.1, Y.sub.1) and B(X.sub.2, Y.sub.2);(c) deriving said compensation parameters by formulas:s=(p.sub.1 x.sub.0 +p.sub.2 y.sub.0)/(x.sub.0.sup.2 +y.sub.0.sup.2)t=(p.sub.2 x.sub.0 -p.sub.1 y.sub.0)/(x.sub.0.sup.2 +y.sub.0.sup.2)m=(q.sub.1 x.sub.0 +q.sub.2 y.sub.0)/(x.sub.0.sup.2 +y.sub.0.sup.2)n=(q.sub.2 x.sub.0 -q.sub.1 y.sub.0)/(x.sub.0.sup.2 +y.sub.0.sup.2)where x.sub.0 =x.sub.2 -x.sub.1, y.sub.0 =y.sub.2 -y.sub.1, p.sub.i =x.sub.3 -x.sub.1, p.sub.2 =y.sub.3 -y.sub.1, q.sub.1 =x.sub.4 -x.sub.1, and q.sub.2 =y.sub.4 -y.sub.1where s, t, m, and n are said compensation parameters deriving by said calculation procedure.