| 摘要 |
PURPOSE:To obtain the beautiful and high-quality graphic data by shaping a graphic with shift of a nodal point and the numerical evaluation of quality given to a loop graphic obtained by applying the direct approximation to a line picture. CONSTITUTION:A line picture is inputted A from a map, etc., and undergoes a line thinning process B. Then the nodal points, i.e., the characteristic points of a graphic are detected, and the linear approximation C is applied to a line graphic via a linear segment connecting the nodal points together. The series of each coordinates value of nodal points forming the line graphic are registered into a loop table D. Then the characteristic value of the graphic is extracted E and a histogram of the characteristic value is produced F. The scattering value of the histogram or the distribution rates gathering in a prescribed range from the peak position of the histogram are obtained as the quality evaluation value to a loop graphic. Thus the loop graphic is evaluated G. Then the nodal points of the loop graphic are moved H within a line width range of an input line graphic, for example, under the prescribed limit conditions for the second extraction of the characteristic value. The quality evaluation is repeated to the histogram or to the loop graphic after the shift of the nodal points. Then the data on the shaped loop graphic is outputted. Thus it is possible to obtain the shaped graphic data free from the graphic distortions. |
