Patent · US Expired

Method for transforming three color input signals to four or more output signals for a color display

US6897876B2 · kind B2 · utility

198Cited by
14References
37Claims
0Family size

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Inventors

Key dates

Filing dateJun 26, 2003
Grant dateMay 24, 2005
Priority date
Expiry dateSep 22, 2023

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG09G2340/06
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

A method for transforming three color input signals (R, G, B) corresponding to three gamut defining color primaries to four color output signals (R′, G′, B′, W) corresponding to the gamut defining color primaries and one additional color primary W for driving a display having a white point different from W includes the steps of: normalizing the color input signals (R,G,B) such that a combination of equal amounts in each signal produces a color having XYZ tristimulus values identical to those of the additional color primary to produce normalized color signals (Rn,Gn,Bn); calculating a common signal S that is a function F1 of the three normalized color signals (Rn,Gn,Bn); calculating a function F2 of the common signal S and adding it to each of the three normalized color signals (Rn,Gn,Bn) to provide three color signals (Rn′,Gn′,Bn′); normalizing the three color signals (Rn′,Gn′,Bn′) such that a combination of equal amounts in each signal produces a color having XYZ tristimulus values identical to those of the display white point to produce three of the four color output signals (R′,G′,B′); and calculating a function F3 of the common signal S and assigning it to the fourth color outp…

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