RGBI to multilevel grey scale encoder
US4739312A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 13, 1986 |
| Grant date | Apr 19, 1988 |
| Priority date | — |
| Expiry date | Jun 13, 2006 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG09G5/028
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
An encoder (500) encodes a TTL type of R,G,B,I video drive signal into a common multilevel grey scale digitally encoded composite video signal which is transmitted over a single coaxial cable (302). The incoming R,G,B,I bits, such as provided from a color computer (304, 306, 308, 310), are buffered and translated (50a, 50b) from TTL to ECL and fed to a common video digital-to-analog converter (100) along with translated composite sync information (312, 314, 10, 324). A white reference level signal is dynamically derived from the translated sync information (200, 202) and provided to the full height input of the video D/A converter (324, 100) which converts the translated R,G,B,I input into a 16 level multibit grey scale code in a linear function from full intensity white to black, with a seventeenth level being provided in the digitally encoded composite video signal to represent sync information.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.