GRAPHIC EXTRACTING SYSTEM

PURPOSE:To extract a monotonous free curve formed with lines other than a straight line as a subject with high accuracy, and to perform the classification of an extracted monotonous curve with high accuracy, by tracing the line in a direction as smooth as possible, deciding the monotony of the line by lengths in an (x) and a (y) directions, and dividing and extracting the monotonous curve by every line width. CONSTITUTION:A picture input part 3 inputs a linear graphic, and stores it at a picture memory part 4, and a thinning part 5 converts the linear graphic accumulated at the picture memory part 4 to a center line, and stores it separately from an input linear graphic at the picture memory 4 as a thinning picture. Next, a line width measur ing part 6 finds the thinning picture memory with line width from the input linear graphic and the thinning picture accumulated at the picture memory part 4, and stores it at the picture memory part 4 separately from the input linear graphic and the thinning picture. Next, a monotonous curve extracting part 7 extracts the monotonous curve one by one from the thinning picture and the thinning picture with line width accumulated at the picture memory part 4, and at last, a picture output part 9 outputs an image setting the value of a picture element stored at a sequence of points memory part 8 as '1', and other picture elements as '0's.