Robert C Cheek

US Patent:

6707572, Mar 16, 2004

Filed:

Aug 18, 1998

Appl. No.:

09/135735

Inventors:

James R. Walker - Maineville OH
Robert D. Cheek - Fairfield OH

Assignee:

Tesseron, Ltd. - Loveland OH

International Classification:

G06F 1500

US Classification:

358 19, 358 15, 358502, 358 306, 358 31, 358 32, 358 33, 358 313, 358 319

Abstract:

A computerized method for controlling the density of pixels deposited by a print engine includes the steps of: (a) obtaining a two-dimensional pixel map of an image to be printed; (b) comparing a value of a first pixel element in the pixel map with values of pixel elements adjacent to the first pixel element in the pixel map; (c) changing the value of the first pixel element responsive to a determination, in the comparing step, that a predetermined number of pixel elements adjacent to the first pixel element have the same value as the first pixel element; and (d) dispatching the pixel map to a print engine. The comparing step (b) includes the steps of assigning like-value pixel elements immediately adjacent to the first pixel element a first weight, assigning like-value pixel elements diagonally adjacent to the first pixel element a second weight, different than the first weight, adding the assigned weights together to produce a total weight, and testing the weight against a predetermined threshold. The changing step includes the step of changing the value of the first pixel element if the total weight is equal to or greater than the predetermined threshold. Alternatively, the changing step is performed if all pixel elements immediately adjacent to the first pixel element have the same value of the first pixel element.