Patent · US Expired

Method and apparatus for generating halftone images by evolutionary screen dot contours

US6198545A · kind A · utility

24Cited by
7References
21Claims
0Family size

Inventors

Key dates

Filing dateMar 27, 1995
Grant dateMar 6, 2001
Priority date
Expiry dateMar 27, 2015

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10S283/902
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

The present invention is related to the synthesis, display and printing of halftone images. The invention comprises a method capable of generating screen elements with sophisticated screen dot shapes such as artistic shapes, microletters and ideograms. The method can be used to generate screen elements whose screen dots are made of evolving artistic shapes at increasing intensity level. For generating screen elements at consecutive intensity levels, intermediate contours which bound the white and black parts of each screen element are obtained by interpolating between fixed predefined contours. Such interpolated contours defining screen dots may be transformed from a screen dot definition space to a screen dot rendition space before being converted into discrete screen elements by a scan conversion and filling operation. Since the method allows producing large screen elements made up of many distinct subscreen dot shapes, the process can be used to generate discrete subscreen elements whose geometry may vary from one subscreen dot to another for the same intensity level. Some subscreen dot shape variations may be used to avoid counterfeiting by photocopying machines and digital sca…

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.