Calibration and merging unit for video adapters
US5835134A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Oct 13, 1995 |
| Grant date | Nov 10, 1998 |
| Priority date | — |
| Expiry date | Oct 13, 2015 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG09G5/12
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
In a computer system, a system video adapter and an add-on video adapter generate video signals according to different dimensional characteristics. The dimensional characteristics of the system adapter are calibrated by a calibration unit so that the video signals can simply be merged. The calibration unit comprises a comparator for detecting pixel signals of calibration lines generated by the system adapter at predetermined horizontal and vertical positions of a display device. The comparator, in response to detecting the pixel signals exceeding a predetermined reference signal, cause a latch to store counts of a counter. The counts represent the horizontal and vertical positions of the detected signals. The counts are presented to the add-on video adapter as calibration parameters. The add-on video adapter can use the calibration parameters to generate video signals which can be directly merged with the video signals of the system video adapter.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.