POLYGONAL LINE APPROXIMATING SYSTEM

摘要

PURPOSE:To attain easily an accurate approximation of a polygonal line by extracting each side out of an original data obtained by dividing an original picture into meshes of a fixed rectangle to obtain the linear data and then extracting both the changing quantity and changing direction showing the slope of segments to said linear data. CONSTITUTION:An exclusive OR is obtained from an original data and the data shifted by a bit toward X and Y axes. Then left and right sides L and R are obtained for the segment of the orignal data. A point that changed by 3 dots (with threshold value set at 3 for distance between two pints) toward X and Y axes is obtained together with a point changed by 3 dots in order to check the inflection degrees to the left and right sides respectively. Then inflection points 1'-5' are extracted at a sampling point. Then an integrated result is obtained by obtaining the average values between points 1' of left and right sides L and R, between points 2' of sides L and R, between points 3' and 4' of the side L and point 3' of the side R and between the final point 5' of the side L and the final point 4' of the side R respectiely.