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. 04, 2004
Filed:
Nov. 01, 1999
Hitoshi Hayama, Shiojiri, JP;
Seiko Epson Corporation, Tokyo, JP;
Abstract
There are provided an image processing method and device. Dithering is executed using a dither matrix of m-valued thresholds (m is an integer ≧2) for comparison with n-valued gradation values (n is an integer ≧3; n≧m). An elementary shape image in a two-valued matrix is formed, for each selected image element of a whole image, which has pixels capable of being divided into ones forming an elementary object image and ones forming an elementary background image, by assigning a validity-indicative value to the former, and an invalidity-indicative value to the latter. For each corresponding selected image element, one of n possible numerical values is stored as a designated gradation value commonly applied to the former. A dither mask in a two-valued matrix identical in size to the dither matrix is stored. This two-valued matrix is formed by assigning the validity-indicative value and the invalidity-indicative value, respectively, to elements of the dither mask corresponding in location to respective ones of the thresholds with reference to which the designated gradation value is made valid, and remaining elements of the same. A dithered image element in a two-valued matrix identical in size to the dither mask is formed by a logical AND operation between each element of each matrix identical in size to the dither mask and constituting the elemetary shape image, and a corresponding one of the elements and the remaining elements.