POLYGONAL LINE APPROXIMATION METHOD OF CURVE

摘要

PURPOSE:To obtain polygonal line approximation of a curve in high speed by thinning out points of a straight line part estimated that they are not selected as points for polygonal line approximation among a sequence of points expressing a curve at the pre-processing to reduce the amount of calculation of arithmetic selecting optimum selecting points. CONSTITUTION:A line drawing inputted by a means 1 inputting the line drawing is sampled by a predetermined time interval and the sampled sequence of point is applied to a pre-processing means 2 of the sequence of points. Partial sequences of points P1, P2- comprising the predetermined partial sequences of points are extracted from a sequence of points P of a curve S by the means 2, and when the sequence of points P1, P2- form a straight line, the midpoint is removed to form the 2nd sequence of points P'1, P'2- are extracted sequentially to form a curve S'. The 2nd sequences of points P'1, P'2- of the curve S' are stored in a memory 3, and the 2nd sequences of points P'1, P'2- stored in the memory 3 are processed by a means 4 solving a recurrence formula, a work memory 5 storing a value of l(i,j) and a memory 6 storing the process of selection of the recurrence formula and the polygonal line approximation of the curve S' is obtained in high speed.