Patent · US Expired

Gamma correction of digital video data by calculating linearly interpolated gamma correction values

US4786968A · kind A · utility

16Cited by
6References
4Claims
0Family size

Assignee

Inventor

Key dates

Filing dateJul 16, 1987
Grant dateNov 22, 1988
Priority date
Expiry dateJul 16, 2007

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04N5/202
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

An apparatus, including a lookup table memory, for gamma correcting a digital video signal based on the assumption that for small gamma, gamma correction is a linear function so that for a digital video input signal value x a gamma correction value d to be added to x can be calculated as a function of an opertor selected variable a according to the formulae: EQU d=10.multidot.0.multidot.(x-x.sup.1.10) EQU or EQU d=10.multidot.9.multidot.(x-x.sup..90 ).

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