Patent · US Expired

Method and apparatus for converting gray scale

US5155478A · kind A · utility

15Cited by
5References
8Claims
0Family size

Assignee

Inventors

Key dates

Filing dateSep 22, 1989
Grant dateOct 13, 1992
Priority date
Expiry dateSep 22, 2009

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04N1/407
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

A system for converting selected M gray levels in a K-gray scale to M identifiable levels in an N-gray scale, where K>N.gtoreq.M. A first table is created in which the respective M gray levels of the K-gray scale are mapped to different levels in the N-gray scale, which levels have the relative order and magnitude of their brightnesses in the K-gray scale, and using this first table, a second table is created in which the M gray levels in the N-gray scale are mapped to their corresponding M gray levels in the K-gray scale on a one-to-one basis according to the first table. Using the second table, any M gray levels in a K-gray scale can easily be converted to ones in an N-gray scale on a one-to-one basis with the relative order and magnitude of the brightnesses of those M gray levels being maintained.

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