Patent ID: 6975431

Claim:
An image processing method of performing a halftone dot processing in which first image data representative of pixel values of a plurality of pixels constituting an image is converted into second image data representative of dot patterns of halftone dots, wherein said image processing method performs the halftone dot processing in which a first dot % of dot patterns, wherein mutually contacting dot patterns first appear with respect to an identical direction on the image, in the event that the halftone dot processing is repeatedly performed while pixel values of pixels on an image comprising a plurality of pixels all of which are same in pixel value are sequentially varied from a lower density end to a higher density end uniformly, is different from a second dot % of dot patterns wherein all the dot patterns, which are adjacent to one another with respect to the identical direction, are in contact with one another, and wherein said first image data is converted into second image data by comparing said pixel values with thresholds of a halftone pattern comprising an arrangement of thresholds, said thresholds of a halftone pattern further comprising a plurality of basic patterns which thresholds are adjusted such that dot patterns are formed which are identical to each other in growth process in respect to shape, but are mutually different from one another in degree of growth.