Patent ID: 7764402

Claim:
A dither matrix generating method of generating a dither matrix for determining a status of dot formation on each of print pixels of a print image to be formed on a print medium in response to input image data, the method comprising: determining a targeted threshold value from among a plurality of threshold values, the targeted threshold value having a highest tendency for dot formation to be On among threshold values for which storage elements are to be determined; determining a storage element for the targeted threshold value from among a plurality of candidate storage elements based on a matrix evaluation value, the matrix evaluation value representing a correlation with a prescribed objective state, the matrix evaluation value being calculated respectively on a presupposition of hypothetical dot On/Off states, the hypothetical dot On/Off states resulting from the targeted threshold value being stored in each of the plurality of candidate storage elements that are candidates for storing the targeted threshold value; and repeating the determining the targeted threshold value and the determining the storage element for at least part of the plurality of threshold values, wherein the determining the storage element includes: extracting an element block that constitutes a group of the storage elements, the element block making up a part of the dither matrix; and selecting the candidate storage elements in succession from among the plurality of storage elements that make up the extracted element block.