System and method for a conference server architecture for low delay and distributed conferencing applications

• US 9,338,213 B2
• Filed: 06/02/2015
• Issued: 05/10/2016
• Est. Priority Date: 09/07/2005
• Status: Active Grant

• Current Assignee: Vidyo Incorporated (Enghouse Systems Limited)
• Original Assignee: Vidyo Incorporated (Enghouse Systems Limited)
• Inventors: Civanlar, Reha Mehmet, Eleftheriadis, Alexandros, Shapiro, Ofer
• Primary Examiner(s): Woo, Stella L
• Application Number:
  US14/728,657
• Publication Number:
  US 20150271243A1
• Time in Patent Office: 343 Days
• US Class Current: 1/1
• CPC Class Codes: H04L 12/4604 LAN interconnection over a backbone network, e.g. Internet, Frame Relay
• CPC Class Codes: H04L 45/22 Alternate routing
• CPC Class Codes: H04L 47/10 Flow control; Congestion control
• CPC Class Codes: H04L 47/2441 relying on flow classification, e.g. using integrated services [IntServ]
• CPC Class Codes: H04L 47/70 Admission control; Resource allocation
• CPC Class Codes: H04L 47/724 at intermediate nodes, e.g. resource reservation protocol [RSVP]
• CPC Class Codes: H04L 47/801 Real time traffic
• CPC Class Codes: H04L 65/403 Arrangements for multi-party communication, e.g. for conferences data switching systems for conference H04L12/18; arrangements for connecting several subscribers to a common circuit, i.e. affording conference facilities H04M3/56; television conferencing systems H04N7/15
• CPC Class Codes: H04L 65/611 for multicast or broadcast systems for broadcast or conference H04L12/18; arrangements for broadcast or distribution combined with broadcast H04H20/00; arrangements for broadcast applications with a direct linkage to broadcast information or to broadcast space-time H04H60/00; selective distribution of broadcast services, e.g. multimedia broadcast multicast service [MBMS], H04W4/06
• CPC Class Codes: H04L 65/80 Responding to QoS
• CPC Class Codes: H04L 67/5683 Storage of data provided by user terminals, i.e. reverse caching
• CPC Class Codes: H04N 19/30 using hierarchical techniques, e.g. scalability H04N19/63 takes precedence
• CPC Class Codes: H04N 21/2662 Controlling the complexity of the video stream, e.g. by scaling the resolution or bitrate of the video stream based on the client capabilities
• CPC Class Codes: H04N 21/6405 Multicasting data broadcast and multicast in packet switching networks H04L12/18
• CPC Class Codes: H04N 21/6408 Unicasting
• CPC Class Codes: H04N 7/152 Multipoint control units therefor

Abstract

Systems and methods for conducting a multi-endpoint video signal conference are provided. Conferencing endpoints are linked by pairs of a reliable and a less reliable communication channel. Conference video signals are scaleable coded in base layer and enhancement layers format. Video signal base layers, which correspond to a minimum picture quality, are communicated over reliable channels. The video signal enhancements layers may be communicated over the less reliable channels. A conference server mediates the switching of video layer information from transmitting endpoints to receiving endpoints without any intermediate coding or re-coding operations. The video conference can be integrated with an audio conference using either scalable coded audio signals or non-scaleable coded audio signals.

Claims

1. A method for conferencing between a transmitting endpoint linked to a scalable video coding server by a first communication channel and at least one receiving endpoint linked to the scalable video coding server by a second communication channel, comprising:

receiving, at the scalable video coding server from the transmitting endpoint, a plurality of media signals having different signal characteristics but representing a same content, each media signal comprising a plurality of packets;

selectively forwarding, by the scalable video coding server, at least one, but not all, of the media signals representing the same content to the at least one receiving endpoint over the second communication channel, wherein the selective forwarding occurs, for each of the plurality of packets, in less than 200 milliseconds; and

improving, by the scalable video coding server, a quality of service of the second communication channel over the quality of service the second communication channel has but for the use of the scalable video coding server.

2. The method of claim 1, wherein the signal characteristics comprise at least one of a spatial resolution, a bit rate, a picture quality, or a frame rate.

3. The method of claim 1, wherein the improving of the quality of service of the second communication channel comprises repeating, by the scalable video coding server, at least one packet of the plurality of packets included in the one of the plurality of media signals.

4. The method of claim 3, wherein the one of the plurality of media signals is the media signal with at least one of the lowest spatial resolution, the lowest bit rate, the lowest picture quality, or the lowest frame rate of all of the plurality of media signals.

5. The method of claim 1, wherein the improving of the quality of service of the second communication channel comprises transmitting, by the scalable video coding server, protected by a Forward Error Correction, at least one packet of the plurality of packets included in the one of the plurality of media signals.

6. The method of claim 5, wherein the one of the plurality of media signals is the media signal with at least one of the lowest spatial resolution, the lowest bit rate, the lowest picture quality, or the lowest frame rate of all of the plurality of media signals.

7. The method of claim 1, wherein the improving of the quality of service of the second communication channel comprises caching, by the scalable video coding server, at least one packet of the plurality of packets included in the one of the plurality of media signals, and retransmit the at least one cached packet upon request by the receiving endpoint.

8. The method of claim 7, wherein the one of the plurality of media signals is the media signal with at least one of the lowest spatial resolution, the lowest bit rate, the lowest picture quality, or the lowest frame rate of all of the plurality of media signals.

9. The method of claim 1, further comprising improving, by the transmitting endpoint, a quality of service of the first communication channel over the quality of service the first communication channel has but for the use of the transmitting endpoint.

10. The method of claim 9, wherein the improving of the quality of service of the first communication channel comprises repeating, by the transmitting endpoint, at least one packet of the plurality of packets included in the one of the plurality of media signals, and discarding, by the scalable video coding server, the repeated packet in case the at least one packet has been received.

11. The method of claim 9, wherein the improving of the quality of service of the first communication channel comprises transmitting, by the transmitting endpoint, protected by a Forward Error Correction, at least one packet of the plurality of packets included in the one of the plurality of media signals, and reconstructing, by the scalable video coding server, the at least one packet in case it was not received by the scalable video coding server, using the Forward Error Correction.

12. The method of claim 9, wherein the improving of the quality of service of the first communication channel comprises caching, by the transmitting endpoint, at least one packet of the plurality of packets included in the one of the plurality of media signals, retransmitting, by the transmitting endpoint, the at least one cached packet upon request by the scalable video coding server, and requesting, by the scalable video coding server, retransmission of the at least one cached packet in case the at least one packet has not been received.

39. The method of claim 1, wherein the improving the quality of service comprises improving the quality of service for all packets of at least one of the at least one media signals.

40. The method of claim 1, wherein one of the at least one media signals having different signal characteristics is a base layer, and another one of the at least one media signals having different signal characteristics is an enhancement layer, and wherein the enhancement layer depends on the base layer.

13. A non-transitory computer readable medium comprising a set of executable instructions to direct a processor to:

receive, at a scalable video coding server from a transmitting endpoint linked to the scalable video coding server by a first communication channel, a plurality of media signals having different signal characteristics but representing a same content, each media signal comprising a plurality of packets;

selectively forward, by the scalable video coding server, at least one, but not all, of the media signals representing the same content to at least one receiving endpoint over a second communication channel, wherein the selective forwarding occurs, for each of the plurality of packets, in less than 200 milliseconds; and

improve, by the scalable video coding server, a quality of service of the second communication channel over the quality of service the second communication channel has but for the use of the scalable video coding server.

14. The non-transitory computer readable medium of claim 13, wherein the signal characteristics comprise at least one of a spatial resolution, a bit rate, a picture quality, or a frame rate.

15. The non-transitory computer readable medium of claim 13, wherein the improve of the quality of service of the second communication channel comprises repeat, by the scalable video coding server, at least one packet of the plurality of packets included in the one of the plurality of media signals.

16. The non-transitory computer readable medium of claim 15, wherein the one of the plurality of media signals is the media signal with at least one of the lowest spatial resolution, the lowest bit rate, the lowest picture quality, the lowest frame rate of all of the plurality of media signals.

17. The non-transitory computer readable medium of claim 13, wherein the improve of the quality of service of the second communication channel comprises transmit, by the scalable video coding server, protected by a Forward Error Correction, at least one packet of the plurality of packets included in the one of the plurality of media signals.

18. The non-transitory computer readable medium of claim 17, wherein the one of the plurality of media signals is the media signal with at least one of the lowest spatial resolution, the lowest bit rate, the lowest picture quality, or the lowest frame rate of all of the plurality of media signals.

19. The non-transitory computer readable medium of claim 13, wherein the improve of the quality of service of the second communication channel comprises cache, by the scalable video coding server, at least one packet of the plurality of packets included in the one of the plurality of media signals, and retransmit the at least one cached packet upon request by the receiving endpoint.

20. The non-transitory computer readable medium of claim 19, wherein the one of the plurality of media signals is the media signal with at least one of the lowest spatial resolution, the lowest bit rate, the lowest picture quality, or the lowest frame rate of all of the plurality of media signals.

21. The non-transitory computer readable medium of claim 13, further comprising executable instructions to direct the processor to improve, by the transmitting endpoint, a quality of service of the first communication channel over the quality of service the first communication channel has but for the use of the transmitting endpoint.

22. The non-transitory computer readable medium of claim 21, wherein improve the quality of service of the first communication channel comprises repeat, by the transmitting endpoint, at least one packet of the plurality of packets included in the one of the plurality of media signals, and discard, by the scalable video coding server, the repeated packet in case the at least one packet has been received.

23. The non-transitory computer readable medium of claim 21, wherein improve the quality of service of the first communication channel comprises transmit, by the transmitting endpoint, protected by a Forward Error Correction, at least one packet of the plurality of packets included in the one of the plurality of media signals, and reconstruct, by the scalable video coding server, the at least one packet in case it was not received by the scalable video coding server, using the Forward Error Correction.

24. The non-transitory computer readable medium of claim 21, wherein improve the quality of service of the first communication channel comprises cache, by the transmitting endpoint, at least one packet of the plurality of packets included in the one of the plurality of media signals, retransmit, by the transmitting endpoint, the at least one cached packet upon request by the scalable video coding server, and request, by the scalable video coding server, retransmission of the at least one cached packet in case the at least one packet has not been received.

25. The non-transitory computer readable medium of claim 13, wherein the improve the quality of service comprises improve the quality of service for all packets of at least one of the at least one media signals.

26. The non-transitory computer readable medium of claim 13, wherein one of the at least one media signals having different signal characteristics is a base layer, and another one of the at least one media signals having different signal characteristics is an enhancement layer, and wherein the enhancement layer depends on the base layer.

27. An apparatus for conferencing, comprising:

a scalable video coding server adapted to be linked to a transmitting endpoint by a first communication channel and at least one receiving endpoint by a second communication channel,

wherein the scalable video coding server is configured to receive from the transmitting endpoint a plurality of media signals having different signal characteristics but representing a same content, each media signal comprising a plurality of packets,

wherein the scalable video coding server is configured to selectively forward at least one, but not all, of the media signals representing the same content to the at least one receiving endpoint over the second communication channel, wherein the selective forwarding occurs, for each of the plurality of packets, in less than 200 milliseconds; and

wherein the scalable video coding server is configured to improve a quality of service of the second communication channel over the quality of service the second communication channel has but for the use of the scalable video coding server.

28. The apparatus of claim 27, wherein the signal characteristics comprise at least one of a spatial resolution, a bit rate, a picture quality, or a frame rate.

29. The apparatus of claim 27, wherein the improving of the quality of service of the second communication channel comprises the scalable video coding server being further configured to repeat at least one packet of the plurality of packets included in the one of the plurality of media signals.

30. The apparatus of claim 29, wherein the one of the plurality of media signals is the media signal with at least one of the lowest spatial resolution, the lowest bit rate, the lowest picture quality, or the lowest frame rate of all of the plurality of media signals.

31. The apparatus of claim 27, wherein the improving of the quality of service of the second communication channel comprises the scalable video coding server being further configured to transmit, protected by a Forward Error Correction, at least one packet of the plurality of packets included in the one of the plurality of media signals.

32. The apparatus of claim 31, wherein the one of the plurality of media signals is the media signal with at least one of the lowest spatial resolution, the lowest bit rate, the lowest picture quality, or the lowest frame rate of all of the plurality of media signals.

33. The conferencing system of claim 27, wherein the improving of the quality of service of the second communication channel comprises the scalable video coding server being further configured to cache at least one packet of the plurality of packets included in the one of the plurality of media signals, and retransmit the at least one cached packet upon request by the receiving endpoint.

34. The apparatus of claim 33, wherein the one of the plurality of media signals is the media signal with at least one of the lowest spatial resolution, the lowest bit rate, the lowest picture quality, or the lowest frame rate of all of the plurality of media signals.

35. The apparatus of claim 27, wherein the transmitting endpoint is configured to improve a quality of service of the first communication channel over the quality of service the first communication channel has but for the use of the transmitting endpoint.

36. The apparatus of claim 35, wherein the improving of the quality of service of the first communication channel comprises the transmitting endpoint being further configured to repeat at least one packet of the plurality of packets included in the one of the plurality of media signals, and the scalable video coding server is further configured to discard the repeated packet in case the at least one packet has been received.

37. The apparatus of claim 35, wherein the improving of the quality of service of the first communication channel comprises the transmitting endpoint being further configured to transmit, protected by a Forward Error Correction, at least one packet of the plurality of packets included in the one of the plurality of media signals, and the scalable video coding server is further configured to reconstruct the at least one packet in case it was not received by the scalable video coding server, using the Forward Error Correction.

38. The apparatus of claim 35, wherein the improving of the quality of service of the first communication channel comprises the transmitting endpoint being further configured to cache at least one packet of the plurality of packets included in the one of the plurality of media signals, and retransmit the at least one cached packet upon request by the scalable video coding server, and the scalable video coding server being further configured to request retransmission of the at least one cached packet in case the at least one packet has not been received.

41. The apparatus of claim 27, wherein the scalable video coding server is configured to improve the quality of service for all packets of at least one of the at least one media signals.

42. The apparatus of claim 27, wherein one of the at least one media signals having different signal characteristics is a base layer, and another one of the at least one media signals having different signal characteristics is an enhancement layer, and wherein the enhancement layer depends on the base layer.