Method of real-time converting analog video signal to digital half-tone data and converters thereof
US4933777A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Apr 26, 1989 |
| Grant date | Jun 12, 1990 |
| Priority date | — |
| Expiry date | Apr 26, 2009 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N1/4058
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
The present invention relates to a method enabling real-time conversion of the analog video signals from a charge coupled element into digital half-tone data which can be printed on a printer or displayed on a display screen and to a converting device which is developed for use with such method. The method according to the present invention serves six primary functions as follows: PA0 1. realization of half-tone patterns and regeneration of gray scales; PA0 2. half-tone models of high compression ratio; PA0 3. method for controlling and adjusting the contrast and brightness; PA0 4. half-tone rules for proportional reduction and enlargement; PA0 5. direct current regeneration of analog video signals; and PA0 6. compensation for uneven illumination. In addition, the present invention provides three embodiments of converter which are adequate to serve the above-mentioned functions in which: The first embodiment uses a framework comprising an analog comparator; The second embodiment uses a framework comprising a flash type analog/digital converter and a digital comparator; and The third embodiment uses a framework comprising a successive approaching register (SAR) type analog/digital c…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.