| 摘要 |
PURPOSE:To accurately generate a mask as correcting partially a false contour gradually by performing the correction of a partial contour line on a picture pattern area and a background area fractionated at a preceding stage by re-setting a slice level at a succeeding stage. CONSTITUTION:An image having a picture pattern is disintegrated to image elements, and a density value of each image element is inputted as data. An outer frame line to enclose the picture pattern is defined, and a histogram for the density value of the image element on the outer frame line is generated. By setting a prescribed slice level on the frequency value of the histogram, the preceding stage to perform the fractionation of the picture pattern area and the background area is performed. In the succeeding stage, the contour line which becomes the boundary of both areas fractionated in such way is extracted at every partial part, and is judged whether or not it is the false contour line. When it is judged as the false contour line, the correction of the contour line of the part is performed by re-setting the slice level. Therefore, an error generated at the preceding stage is corrected at the succeeding stage, then, an accurate mask without generating the error can be generated. |
