Patent · US Expired

Backing luminance non-uniformity compensation in real-time compositing systems

US5940140A · kind A · utility

12Cited by
4References
17Claims
0Family size

Assignee

Inventors

Key dates

Filing dateSep 10, 1996
Grant dateAug 17, 1999
Priority date
Expiry dateSep 10, 2016

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04N9/75
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

A method of removing the foreground subject and its shadow from a series of image frames including a subject before a colored backing being photographed by a moving camera during a live broadcast. Such removal results in a series of image frames of the colored backing without the subject, each image frame corresponding to an image frame containing the subject. The method steps employed identify, for each frame, those pixels in the frame occupied by elements of the subject. Those pixels are set to an RGB level of zero, to create an image of the colored backing in which the subject area is reduced to black. The image of the colored backing is then smeared to obliterate the defined edges of the subject's shadow and to smear the color of the backing into the black area previously occupied by the subject to generate a clear frame. The clear frame is then utilized to compensate for backing luminance and color nonuniformity, thereby preventing visibility of the joining edge of generated windows that extend the backing to the edge of the frame.

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