Patent · US Expired

Ink relocation for color halftones

US5991512A · kind A · utility

21Cited by
1References
32Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJul 31, 1997
Grant dateNov 23, 1999
Priority date
Expiry dateJul 31, 2017

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04N1/58
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

Current methodologies for color image halftoning produce prominent halftoning noise. Brightness variations between color dots placed at neighboring locations are a primary cause of color halftone noise. To correct this flaw, an Ink Relocation Postprocess to halftoning algorithms relocates ink drops between neighboring drop locations in order to reduce local brightness variations. Due to the intrinsic blurring side-effect of ink relocation, some enhancement may be desired. Two application-specific enhancement procedures are presented. In the first enhancement, ink relocation is suppressed in areas of fine detail. In the second enhancement, edge sharpening is performed after ink relocation.

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