Selective control of window related overlays and underlays
US5386505A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Nov 30, 1993 |
| Grant date | Jan 31, 1995 |
| Priority date | — |
| Expiry date | Nov 30, 2013 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG09G5/06
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
Apparatus and methods for selectively controlling by window the number of overlay planes, the number of overlay palettes, and the overlay/underlay plane masks in a graphics video display system. A logic/multiplex control translates overlay and underlay data patterns from a multiple plane VRAM (Video Random Access Memory), referenced to the graphics system frame buffer, into window specific patterns. The window related translation is conveyed to conventional RAMDACs (Random Access Memory Digital-to-Analog Converters) for raster scan synchronized digital-to-analog conversion. The translation as provided by the controller is responsive to data selectively and dynamically written into a random access memory, thus providing translation of overlay/underlay data into window distinct and selective overlay/underlay palette functions.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.