Patent · US Expired

Image scanner

US5329382A · kind A · utility

6Cited by
13References
3Claims
0Family size

Assignee

Inventor

Key dates

Filing dateDec 11, 1991
Grant dateJul 12, 1994
Priority date
Expiry dateDec 11, 2011

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04N1/409
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

A document image scanner that converts scanned images for output as bilevel images is provided with a bilevel image filter. The bilevel image filter counts the number of continuous pattern elements in each direction, vertical, horizontal and diagonal, from a specific point and compares the results with a predetermined reference. Patterns falling below the reference value are regarded as resulting from background noise and are erased.

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