Patent · US Expired

Color image processing with adjustment of computed recording color to match original color

US5270808A · kind A · utility

116Cited by
10References
27Claims
0Family size

Assignee

Inventor

Key dates

Filing dateMar 1, 1993
Grant dateDec 14, 1993
Priority date
Expiry dateMar 1, 2013

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04N1/52
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

There is disclosed a color image processing method and apparatus therefor, in which the input image data are converted into a color coordinate system represented by luminosity and hue, for example L*a*b* space. The colors reproducible on the output device, for example a printer, are also converted into this coordinate system. An average value is calculated over plural pixels in the vicinity of an object pixel to be digitized, and plural average values are then obtained by including the object pixel selected at each of the reproducible colors. The input image signal is digitized to the closest one of the plural average signals. The digitization error generated upon digitization is distributed to the succeeding pixels with weighted ratios. This method achieves faithful color reproduction, matching the colors reproducible on the recording or display device.

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