Patent · US Expired

Image signal processing device

US4468703A · kind A · utility

37Cited by
3References
4Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMay 14, 1982
Grant dateAug 28, 1984
Priority date
Expiry dateMay 14, 2002

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04N1/403
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

An image signal processing device uses an automatically varied threshold value calculated from the average density and the density distribution of an original (document, etc). The threshold value is periodically updated at predetermined intervals, so that the overall image may be reproduced with high fidelity.

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