Patent · US Expired

Video conferencing system using spatial reduction and temporal resolution

US4004084A · kind A · utility

47Cited by
3References
11Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMar 3, 1976
Grant dateJan 18, 1977
Priority date
Expiry dateMar 3, 1996

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04N7/15
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

Video conferencing, wherein the outputs of a plurality of television cameras at one location are transmitted to a second location so that parties at the first location are perceived as present by parties at the second location, has received some attention directed toward bandwidth reduction. The subject invention relates to an improved video conferencing system for reducing bandwidth by advantageously applying temporal resolution and spatial reduction to a video picture provided by each camera. The temporal resolution of a picture from one or more of the cameras can be automatically adapted to a control signal, for example, to a speech level control signal so as to advantageously interleave and to give priority to a picture from one camera over a picture from other television cameras. The spatial reduction of each picture obtains by transmitting and displaying less than the total picture, illustratively the middle two-thirds of the picture from each camera.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.