Low bandwidth video teleconferencing system and method
US4710813A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jul 31, 1986 |
| Grant date | Dec 1, 1987 |
| Priority date | — |
| Expiry date | Jul 31, 2006 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N19/20
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A low bandwidth video teleconferencing system and method is disclosed. The video teleconferencing system employs novel data compression techniques by which continuous transmission of imagery at a rate of 9600 bits/second is possible. A sketch coder converts the grey scale image to be transmitted to a sketch or line drawing, which comprises an outline of the principal boundaries plus shading to represent depth. The bandwidth required for the data representing the sketch is then compressed by two-dimensional run length coding techniques which exploit interframe and interline redundancy as well as intraline redundancy to generate a binary transmission code. Other features are also provided.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.