Patent · US Expired

Apparatus and accompanying methods for achieving automatic color balancing in a film to video transfer system

US4945406A · kind A · utility

65Cited by
20References
30Claims
0Family size

Assignee

Inventor

Key dates

Filing dateNov 7, 1988
Grant dateJul 31, 1990
Priority date
Expiry dateNov 7, 2008

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04N9/11
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

Apparatus and accompanying methods for use in a film to video transfer system for achieving automatic color balancing of color images for subsequent display on a color monitor. Specifically, this apparatus first transforms each pixel in an image to be transferred from logarithmic exposure ("log exposure") RGB color values into corresponding printing density values through local averaging, then utilizes a printing density based color correction method to generate a color correction offset value for each of the RGB primary colors, and finally converts the three resulting RGB color correction offset values from the printing density domain back to the log exposure domain wherein each offset value is subsequently used to correct the corresponding red, green and blue color values associated with each of the pixels that collectively forms a subsequent scan of the same image prior to the conversion of each of the color balanced RGB pixel values into analog video form.

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