Still picture transmission apparatus
US4561020A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jun 6, 1983 |
| Grant date | Dec 24, 1985 |
| Priority date | — |
| Expiry date | Jun 6, 2003 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N1/00095
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A still picture transmission apparatus operable in the quad-split mode, includes a switcher device for receiving a plurality of video signals and for transmitting the received video signals one at a time in a sequential manner. The switcher transmitted video signals are compressed and stored at defined locations of a suitable memory for subsequent transmission over a transmission line. To increase efficiency, each sequentially selected video signal is investigated to determine if it contains video information. If it is found that no video information is present, the switcher is directed to immediately select the next video signal and not wait out the time period normally allowed for the compression, storage and transmission of video information. The video signals are investigated by detecting the presence or absence of a television synchronizing signal in each of the video signals.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.