US4004084A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Video conferencing system using spatial reduction and temporal resolution
Assignee: AT&T Inc
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Filing: 1976-03-03
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Granted: 1977-01-18
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Expires: 1996-03-03
Abstract
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.
Inventors
- 👤 Earl Franklin Brown
- 👤 John Ormond Limb
- 👤 Birendra Prasada
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 13:36
CPC Classifications
H; H04; H04N; H04N7/00; H04N7/08; H04N7/0806; H04N7/14; H04N7/15
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
141 words
In a video conferencing system, apparatus for reducing bandwidth of a plurality of video pictures; each picture having one or more fields, each picture being provided by a corresponding one of a plurality of video cameras, and each picture for display on a corresponding one of a plurality of video monitors; said apparatus including means for spatially reducing a picture from a first group of one or more cameras, said spatial reduction means including means for providing a spatial portion of said picture from said first group of cameras, said spatial portion being less than the total raster of a picture and CHARACTERIZED IN THAT said apparatus further comprises: temporal resolution means operative upon said picture from said first group of cameras, said temporal resolution means including means for interleaving each picture in said first group in a prefixed rotational sequence.
Claim 2
Dependent Claim
141 words
In a video conferencing system, apparatus for reducing bandwidth of a plurality of video pictures; each picture having one or more fields, each picture being provided by a corresponding one of a plurality of video cameras, and each picture for display on a corresponding one of a plurality of video monitors; said apparatus including means for spatially reducing a picture from a first group of one or more cameras, said spatial reduction means including means for providing a spatial portion of said picture from said first group of cameras, said spatial portion being less than the total raster of a picture and CHARACTERIZED IN THAT said apparatus further comprises: temporal resolution means operative upon said picture from said first group of cameras, said temporal resolution means including means for interleaving each picture in said first group in a prefixed rotational sequence.
Claim 3
Dependent Claim
34 words
The apparatus defined in claim 1 wherein said spatial portion providing means includes means for improving picture detail, said picture detail improving means including means for providing more than one-half of said total raster.
Claim 4
Dependent Claim
33 words
The apparatus defined in claim 1 further comprising: means responsive to a control signal for replacing said first group of pictures with a picture from a second group of one or more cameras.
Claim 5
Dependent Claim
36 words
The apparatus defined in claim 1 further comprising: means adapted to detect a predetermined control signal, and means responsive to said detected control signal for selectively adjusting said temporal resolution of said first group of pictures.
Claim 6
Dependent Claim
21 words
The apparatus defined in claim 4 wherein said predetermined control signal detecting means includes means adapted to receive a speech signal.
Claim 7
Dependent Claim
35 words
The apparatus defined in claim 1 wherein said interleaving means includes means for improving video presence, said video presence means including means for selectively interleaving a predetermined field of each picture from said first group.
Claim 8
Dependent Claim
134 words
In a video conferencing system, apparatus for reducing bandwidth of a plurality of video signals, each signal having one or more fields and each signal being provided by a corresponding one of a plurality of sources, each source having one or more video cameras, said apparatus comprising means for spatially reducing a video picture from a first group of cameras in each source, said spatial reduction means including means for providing a spatial portion of said video picture, said spatial portion being less than the total raster of said video picture; means coupled to said spatial reduction means for temporally resolving each said spatially reduced video picture, said temporal resolution means including means for selectively transmitting a predetermined field of said picture; and receiver means for linearly interpolating a nontransmitted field of said picture.
Claim 9
Dependent Claim
134 words
In a video conferencing system, apparatus for reducing bandwidth of a plurality of video signals, each signal having one or more fields and each signal being provided by a corresponding one of a plurality of sources, each source having one or more video cameras, said apparatus comprising means for spatially reducing a video picture from a first group of cameras in each source, said spatial reduction means including means for providing a spatial portion of said video picture, said spatial portion being less than the total raster of said video picture; means coupled to said spatial reduction means for temporally resolving each said spatially reduced video picture, said temporal resolution means including means for selectively transmitting a predetermined field of said picture; and receiver means for linearly interpolating a nontransmitted field of said picture.
Claim 10
Dependent Claim
41 words
The apparatus defined in claim 7 further comprising: means for providing a predetermined control signal; and means responsive to said control signal for selectively adjusting said temporal resolution of said spatially reduced picture from at least one of said signal sources.
Claim 11
Dependent Claim
17 words
The apparatus defined in claim 8 wherein said predetermined control signal is a speech level control signal.
Claim 12
Dependent Claim
26 words
The apparatus defined in claim 9 wherein said temporal resolution selective adjusting means are responsive to a predetermined threshold level of said speech level control signal.
Claim 13
Dependent Claim
43 words
The apparatus defined in claim 7 further comprising: means for providing a predetermined control signal and means reponsive to said control signal for selectively adjusting said temporal resolution of a picture from a second group of one or more cameras at each source.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1980-01-18 | 1980-07-19 | 1981-01-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-01-18 | 1984-07-19 | 1985-01-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-01-18 | 1988-07-19 | 1989-01-18 | $7700.00 | Window Closed / Lapsed |