Terry W Downs

US Patent:

56336543, May 27, 1997

Filed:

Mar 16, 1995

Appl. No.:

8/406094

Inventors:

Howard J. Kennedy - Hamilton Square NJ
Josh Herman - Beaverton OR
Rich Gerber - Hillsboro OR
Dan Harwell - Upper Black Eddy PA
Gerald Cross - Philadelphia PA
Judi Goldstein - Hillsboro OR
Terry Downs - Forest Grove OR
Mike Hawash - Beaverton OR

Assignee:

Intel Corporation - Santa Clara CA

International Classification:

G09G 500

US Classification:

345114

Abstract:

Video data for two or more video streams are processed by a single background command list containing one or more background commands and a single foreground command list containing one or more foreground commands, where the foreground command list is implemented only during a vertical blanking interval of the display raster of a monitor. The processed video data are then displayed during the raster period. In a preferred embodiment, if the implementation of a background command has not completed by the start of a vertical blanking interval, the background command is interrupted, the state of the background command implementation is saved, the foreground command list is implemented, and then the interrupted background command is resumed. The background commands are preferably those that do not directly affect the display bitmaps, while the foreground commands are those that do directly affect the display bitmaps. The invention assures proper synchronization of video data processing and raster-based video display.