Patent · US Expired

Color key detection scheme for multimedia systems

US5644333A · kind A · utility

8Cited by
5References
6Claims
0Family size

Assignee

Inventors

Key dates

Filing dateDec 12, 1994
Grant dateJul 1, 1997
Priority date
Expiry dateDec 12, 2014

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG09G2340/12
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

This method is most advantageous when an analog multiplexer is controlled to pass either analog graphics signals or analog motion video signals to a multimedia display screen. In the preferred embodiment, this method includes the steps of outputting a digital color key from a graphics memory buffer at a designated time and for a designated period and then converting this color key to an analog signal. This analog color key signal is then detected during this designated period and stored to obtain a stored color key value. The graphics memory is then controlled to output the graphics signals to be displayed on a multimedia screen. These graphics signals include a digital color key for controlling a multiplexer to display a motion video window on the multimedia screen in place of the color key. The outputted graphics signals are converted into analog signals, and these analog signals are compared to the stored color key value for detecting whether a color key is being outputted in the graphics data stream. When the analog graphics signal matches the stored color key value, the multiplexer is controlled to pass motion video signals to the multimedia screen for displaying a video windo…

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