Method and apparatus for removing an image from a window of a display
US4876533A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Oct 18, 1988 |
| Grant date | Oct 24, 1989 |
| Priority date | — |
| Expiry date | Oct 18, 2008 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG09G5/14
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
An image within a window on a scanned display device driven by a video generator is replaced with a preselected background color within one frame. The contents of the memory used to refresh the display can thus be changed in a background mode so that the user is unaware of the operation which he or she perceives as "instantaneous". Circuitry determines whether the scan is within the boundaries of the window and, if it is, generates a forcing signal which directs a look-up table within the video generator to a predetermined address which corresponds to a preselected background color. The invention can utilize existing circuitry in the video generator for generating synchronizing and blanking signals.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.