ABSTRACT PATTERN PLATE MAKING SYSTEM FOR PRINTING BUILDING MATERIAL

摘要

PURPOSE:To remove unevenness in density automatically and in a short time by providing a second means to delete a given frequency region through secondary Fourier conversion of pattern data produced by a first means and thereafter remove an undesired pattern through reverse Fourier transform. CONSTITUTION:A unit raw material on a basis of which an abstract pattern is formed is decomposed into picture elements in given density by an input scanner 1, which effects reading. Longitudinal and lateral watermark synthesis is effected on picture data of the unit raw material read by the input scanner 1 the given number of times by means of a first means equivalent to an endless processing part 9 to produce pattern data having a given size. When unevenness in density by which production of an undesired pattern equivalent to a pattern curl is caused occurs to the pattern data, secondary Fourier transform of pattern data produced by the first means is effected to delete a given frequency region, and reverse Fourier transform is made on a Fourier transform picture after erasion.