The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
May. 12, 2009
Filed:
Jan. 06, 2006
Hiroshi Asai, Kyoto, JP;
Masayuki Nakano, Kyoto, JP;
Yasuhiro Takemoto, Kyoto, JP;
Dainippon Screen Mfg. Co., Ltd., Kyoto, JP;
Abstract
In a threshold matrix generation partimplemented by a computer, a tint image in a specified gray level is generated from temporary lighting order set in a matrix area, and a smoothing operation is performed on the tint image, to generate a grayscale evaluation image. The lighting order is modified by changing ordinal numbers in the lighting order of respective positions included in specified areas in the matrix area which correspond to areas around boundaries of halftone dot areas in the tint image on the basis of values of corresponding pixels in the evaluation image. With this operation, when the smoothing operation is performed on a tint image in the specified gray level generated in accordance with a modified lighting order, a variation among values of pixels included in the specified areas becomes smaller than a variation among values of pixels included in the specified areas in a case where the smoothing operation is performed on the tint image in the specified gray level generated in accordance with an unmodified lighting order. Then, threshold values are determined in the matrix area with reflecting the modified lighting order, to generate the threshold matrix which is possible to suppress graininess in a generated halftone dot image.