Multi-point videoconference system having a fixed control station for data transfer

• US 5,821,985 A
• Filed: 10/10/1997
• Issued: 10/13/1998
• Est. Priority Date: 02/28/1995
• Status: Expired due to Term

• Current Assignee: NEC Engineering Limited
• Original Assignee: NEC Corporation
• Inventors: Iizawa, Junichi
• Primary Examiner(s): Chan, Wing F.
• Application Number:
  US08/948,488
• Time in Patent Office: 368 Days
• Field of Search: 348/14-20, 379/93.01, 379/93.14, 379/93.17, 379/93.21, 379/93.28, 379/202-207, 370/260, 370/265
• US Class Current: 348/14.09
• CPC Class Codes: H04M 3/567 Multimedia conference systems
• CPC Class Codes: H04N 7/152 Multipoint control units therefor

Abstract

A plurality of local stations each respectively have terminal equipment for coding in a compressing manner and multiplexing audio data, video data and cnotrol data of the local station to obtain a first multiplex data, and demultiplexing and decoding in a decompressing manner a second multiplex data input thereto from a control station connected by a communication line to the local station. The control station has a multi-point videoconference controller for responding to the control data in the first multiplex data from any local station to process the first multiplex data from a selected station, to generate the second multiplex data to be transmitted to each of other local stations than the selected station. The second multiplex data to the other local stations includes the audio data and the video data in the first multiplex data from the selected station.

Claims

1. A multi-point videoconference system, comprising:

a plurality of local stations each producing its own data, said own data including audio data, video data and control data capable of including at least one of a request for voice and a request for video, said local stations each having terminal equipment adapted to at least (i) code in a compressing manner and multiplex said own data to obtain first multiplex data, (ii) output said first multiplex data, and (iii) demultiplex and decode in a decompressing manner second multiplex data input thereto to obtain reproduced data to be presented by said local station;

a control station having a multi-point videoconference controller adapted to (i) respond to said control data of said first multiplex data transmitted thereto from said local stations, (ii) recognize one of said local stations as a selected station, (iii) process said first multiplex data from said selected station to generate said second multiplex data, (iv) transmit said second multiplex data which includes said audio data and said video data of said first multiplex data of said selected station to each of said local stations other than said selected station, (v) process said first multiplex data from an arbitrary one of said local stations, which includes said at least one request, to produce said second multiplex data, including said request, for delivery only to said selected station, and (vi) add at least one of said voice data and said video data of said arbitrary station to said second multiplex data for transmission to said local stations other than said arbitrary station when said selected station grants said request; and

a plurality of communication lines interconnecting said control station with said local stations in a one to one corresponding manner for transmitting said first multiplex data and said second multiplex data.

2. The multi-point videoconference system as claimed in claim 1, wherein said multi-point videoconference controller is adapted to respond to a cancel instruction contained in said control data of said first multiplex data from said arbitrary station, by ceasing to respond to said request received from said arbitrary station.

3. The multi-point videoconference system as claimed in claim 1, wherein said multi-point videoconference controller is adapted to respond to a permission of request signal contained in said control data of said selected station which indicates that said request of said arbitrary station is granted.

4. The multi-point videoconference system as claimed in claim 3, wherein said multi-point videoconference controller is adapted to respond to a cancel instruction contained in said control data of said first multiplex data from said selected station by ceasing to respond to said permission of request signal received from said selected station.

5. The multi-point videoconference system as claimed in claim 1, wherein said multi-point videoconference controller is adapted to (i) respond to an addition instruction contained in said first multiplex data from said selected station by processing said first multiplex data of least one of said local stations such that said second multiplex data includes said audio data and said video data of said at least one local station, and (ii) transmit said second multiplex data to each of said local stations except said at least one local station.

6. The multi-point videoconference system as claimed in claim 1, wherein said multi-point videoconference controller is adapted to respond to a station select instruction contained in said first multiplex data from said selected station such that only a number of local stations determined by said select instruction receive said second multiplex data.

7. The multi-point videoconference system as claimed in claim 1, wherein said multi-point videoconference controller is adapted to respond to a display instruction contained in said first multiplex data from said selected station such that corresponding reproducible display data is added to said second multiplex data for display by each of said local stations.

8. The multi-point videoconference system as claimed in claim 1, wherein said terminal equipment at each local station is provided with peripheral equipment including a local controller for generating said control data of each said local station.

9. The multi-point videoconference system as claimed in claim 8, wherein said local controller of each of said other stations is operable to provide said control data with said request and to cancel said request;

and

said local controller of said selected station is operable to provide said control data with a permission of request signal granting said request and to cancel said permission of request signal.

10. The multi-point videoconference system as claimed in claim 8, wherein said local controller of said selected station is operable to provide said control data with an instruction to said multi-point videoconference controller.

11. The multi-point videoconference system as claimed in claim 1, wherein said multi-point videoconference controller is adapted to (i) respond to a voice signal in said audio data in said first multiplex data from an arbitrary station of said local stations when said audio data in said first multiplex data from said selected station includes no voice data, (ii) process said first multiplex data from said arbitrary station to generate said second multiplex data which includes at least said audio data of said first multiplex data from said arbitrary station, and (iii) transmit said second multiplex data to said local stations other than said arbitrary station.

12. The multi-point videoconference system as claimed in claim 1, wherein said selected station is programmed in said multi-point videoconference controller.

13. A multi-point videoconference method for a system including a control station and a plurality of local stations each having its own data comprising audio data, video data and control data capable of including at least one of a request for voice and a request for video, the method comprising the steps of:

establishing a selected local station;

coding in a compressing manner and multiplexing said own data to obtain first multiplex data at each local station;

transmitting said first multiplex data of each local station through a communication line connecting said local station to said control station;

responding, at the control station, to said control data in said first multiplex data from any local station by processing said first multiplex data from said selected local station to generate second multiplex data which includes said audio data and said video data from said selected station;

transmitting said second multiplex data from said control station through said communication line to each of said local stations other than said selected station;

demultiplexing and decoding in a decompressing manner the second multiplex data to obtain reproduced data at each of said other local stations;

responding to an arbitrary one of said local stations, which includes said at least one request, by producing said second multiplex data including said request and delivering said data only to said selected station; and

adding said first multiplex data of said arbitrary station to said second multiplex data for transmission to said local stations other than said arbitrary station when said selected station grants said request.