Eric S Bean

US Patent:

55420524, Jul 30, 1996

Filed:

Jan 26, 1994

Appl. No.:

8/188246

Inventors:

Keith R. Deutsch - Amherst NH
Per H. Bjorge - Hollis NH
Alan Blannin - Amherst NH
Eric J. Bean - Kent WA
Douglas L. Peltonen - Seattle WA
Timothy H. Roth - Issaquah WA

Assignee:

Adobe Systems Incorporated - Mountain View CA

International Classification:

G06T 1140

US Classification:

395131

Abstract:

A trapping technique that accepts a Postscript or other page description language (PDL) file and outputs a file in PDL format having the correct traps. The input page is first divided into subportions, or tiles, and the tiles are individually processed by evaluating the input file in a corresponding dipping window. Each tile is then analyzed to determine the presence of boundaries or intersections between page objects or color regions. A trapping analyzer generates trap vectors in accordance with a set of desired trapping rules which take into account existing traps and the proximity of other page objects. In a preferred embodiment, the trap vectors are then convened to PDL form.