System and method for performing distributed video conferencing

• US 7,477,282 B2
• Filed: 07/12/2005
• Issued: 01/13/2009
• Est. Priority Date: 10/08/2003
• Status: Active Grant

• Current Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Original Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Inventors: Surazski, Luke K., Wu, Duanpei, Lantz, Keith A., Sarkar, Shantanu, Friedrich, Walter R., Firestone, Scott S., Ismail, Nermin M.
• Primary Examiner(s): Ramakrishnaiah; Melur
• Application Number:
  US11/180,826
• Publication Number:
  US 20050248652A1
• Time in Patent Office: 1,281 Days
• Field of Search: 348 1401- 1409, 348 14- 1, 348 1411- 1416, 348/500, 348/512, 348/513, 370260-263, 379/202.01, 709/204
• US Class Current: 348/14.09
• CPC Class Codes: H04L 12/1822 Conducting the conference, e.g. admission, detection, selection or grouping of participants, correlating users to one or more conference sessions, prioritising transmission
• CPC Class Codes: H04L 65/4046 with distributed floor control
• CPC Class Codes: H04L 65/765 intermediate
• CPC Class Codes: H04M 3/567 Multimedia conference systems
• CPC Class Codes: H04N 7/15 Conference systems
• CPC Class Codes: H04N 7/152 Multipoint control units therefor

Abstract

A method for executing a video conference is provided that includes receiving one or more audio streams associated with a video conference from one or more end points and determining an active speaker associated with one of the end points. Audio information associated with the active speaker may be received at one or more media switches. One or more video streams may be suppressed except for a selected video stream associated with the active speaker, the selected video stream propagating to one or more of the media switches during the video conference. The selected video stream may be replicated such that it may be communicated to one or more of the end points associated with a selected one of the media switches.

Claims

1. An apparatus for performing distributed video conferencing, comprising:

a media switch operable to communicate with an audio bridge that is operable to receive audio data from a first and a second end point for a conference call, wherein the media switch can also communicate with a video bridge operable to receive video data from the first and second end points, and wherein an input-to-output mapping is determined for each input audio output stream from the end points to a mixed audio stream, whereby the mapping can be communicated to the video bridge that can receive one or more video streams and delay each of the video streams such that the mapping may be reproduced, and wherein the video streams that are arriving at a latest time are identified and all of the other video streams are delayed such that an input-to-output matching of each individual video stream is matched to the mapping of a corresponding audio stream.

2. The apparatus of claim 1, wherein the media switch is further operable to register its capabilities at startup of the conference call.

3. The apparatus of claim 1, wherein a mixed output video stream may be created by mixing the delayed video streams, whereby the mixed outputs from the audio bridge and the video bridge may be communicated back to each of the first and second end points such that the conference call is facilitated.

4. The apparatus of claim 1, wherein the media switch is further operable to perform audio mixing that mixes audio of loudest speakers and to distribute loudest speaker information to another media switch.

5. The apparatus of claim 1, wherein the media switch is further operable to perform video composition, which processes video by creating a composite view of a set of participants in the conference call.

6. The apparatus of claim 1, wherein the media switch is further operable to perform audio transcoding that provides audio transcoding or codec translation services that can be used by network devices without forcing the network devices to employ digital signal processing resources to perform audio transcoding on their own.

7. The apparatus of claim 1, further comprising:

a gateway operable to provide connectivity to the media switch that is operable to facilitate participation in the conference call by the first and second end points.

8. The apparatus of claim 1, further comprising:

a call manager operable to provide a communicative platform from which the first and second end points can participate in the conference call.

9. The apparatus of claim 1, wherein the media switch is further operable to perform video transcoding that provides video transcoding or codec translation services that can be used by network devices without forcing the network devices to employ digital signal processing resources to perform video transcoding on their own.

10. The apparatus of claim 1, wherein the media switch is further operable to perform video transrating that provides a video transrating service, which can offer bandwidth reduction by changing video quantization parameters, whereby the service can be used by network devices without forcing the network devices to employ digital signal processing resources to perform video transrating on their own.

11. The apparatus of claim 1, wherein the media switch is further operable to perform media switching that represents an interface between an edge of a network, which is toward the end points, and a core of the network, which is toward other media switches.

12. The apparatus of claim 1, wherein the media switch is provided in a router, a switch, a general-purpose operating system, a wireless access point, or a gateway.

13. The apparatus of claim 1, wherein the media switch is responsible for replicating packets in order to fan out unidirectional video streams such that other media switches participating in the conference call can receive them.

14. The apparatus of claim 1, wherein any input or output call legs associated with the conference call may use point-to-point or multicast call legs, whereby an edge transport mechanism is independent of a core transport mechanism for a network.

15. The apparatus of claim 1, wherein within a core of a network between several media switches, a single UDP control port is open on at least some of the media switches, whereby the control port can be shared, for purposes of control, by all end points associated with each respective media switch.

16. A method for performing distributed video conferencing, comprising:

communicating with an audio bridge that is operable to receive audio data from a first and a second end point for a conference call; and

communicating with a video bridge operable to receive video data from the first and second end points, wherein an input-to-output mapping is determined for each input audio output stream from the end points to a mixed audio stream, whereby the mapping can be communicated to the video bridge that can receive one or more video streams and delay each of the video streams such that the mapping may be reproduced, and wherein the video streams that are arriving at a latest time are identified and all of the other video streams are delayed such that an input-to-output matching of each individual video stream is matched to the mapping of a corresponding audio stream.

17. The method of claim 16, further comprising:

registering audio and video capabilities at startup of the conference call.

18. The method of claim 16, further comprising:

creating a mixed output video stream by mixing the delayed video streams, whereby the mixed outputs from the audio bridge and the video bridge may be communicated back to each of the first and second end points such that the conference call is facilitated.

19. The method of claim 16, further comprising:

performing audio mixing that mixes audio of loudest speakers; and

distributing loudest speaker information to another media switch.

20. The method of claim 16, further comprising:

performing video composition, which processes video by creating a composite view of a set of participants in the conference call.

21. The method of claim 16, further comprising:

performing audio transcoding that provides audio transcoding or codec translation services that can be used by network devices without forcing the network devices to employ digital signal processing resources to perform audio transcoding on their own.

22. The method of claim 16, further comprising:

performing media switching that represents an interface between an edge of a network, which is toward the end points, and a core of the network, which is toward other media switches.

23. The method of claim 16, further comprising:

replicating packets in order to fan out unidirectional video streams such that other media switches participating in the conference call can receive them.

24. A system for performing distributed video conferencing, comprising:

means for communicating with an audio bridge that is operable to receive audio data from a first and a second end point for a conference call; and

means for communicating with a video bridge operable to receive video data from the first and second end points, wherein an input-to-output mapping is determined for each input audio output stream from the end points to a mixed audio stream, whereby the mapping can be communicated to the video bridge that can receive one or more video streams and delay each of the video streams such that the mapping may be reproduced, and wherein the video streams that are arriving at a latest time are identified and all of the other video streams are delayed such that an input-to-output matching of each individual video stream is matched to the mapping of a corresponding audio stream.

25. The system of claim 24, further comprising:

means for registering audio and video capabilities at startup of the conference call.

26. The system of claim 24, further comprising:

means for creating a mixed output video stream by mixing the delayed video streams, whereby the mixed outputs from the audio bridge and the video bridge may be communicated back to each of the first and second end points such that the conference call is facilitated.

27. The system of claim 24, further comprising:

means for performing audio mixing that mixes audio of loudest speakers; and

means for distributing loudest speaker information to another media switch.

28. The system of claim 24, further comprising:

means for performing video composition, which processes video by creating a composite view of a set of participants in the conference call.

29. The system of claim 24, further comprising:

means for performing audio transcoding that provides audio transcoding or codec translation services that can be used by network devices without forcing the network devices to employ digital signal processing resources to perform audio transcoding on their own.

30. The system of claim 24, further comprising:

means for performing media switching that represents an interface between an edge of a network, which is toward the end points, and a core of the network, which is toward other media switches.

31. The system of claim 24, further comprising:

means for replicating packets in order to fan out unidirectional video streams such that other media switches participating in the conference call can receive them.

32. Software for performing distributed video conferencing, the software being embodied in a computer readable medium and comprising computer code such that when executed is operable to:

communicate with an audio bridge that is operable to receive audio data from a first and a second end point for a conference call; and

communicate with a video bridge operable to receive video data from the first and second end points, wherein an input-to-output mapping is determined for each input audio output stream from the end points to a mixed audio stream, whereby the mapping can be communicated to the video bridge that can receive one or more video streams and delay each of the video streams such that the mapping may be reproduced, and wherein the video streams that are arriving at a latest time are identified and all of the other video streams are delayed such that an input-to-output matching of each individual video stream is matched to the mapping of a corresponding audio stream.

33. The medium of claim 32, wherein the code is further operable to:

register audio and video capabilities at startup of the conference call.

34. The medium of claim 32, wherein the code is further operable to:

create a mixed output video stream by mixing the delayed video streams, whereby the mixed outputs from the audio bridge and the video bridge may be communicated back to each of the first and second end points such that the conference call is facilitated.

35. The medium of claim 32, wherein the code is further operable to:

perform audio mixing that mixes audio of loudest speakers; and

distribute loudest speaker information to another media switch.

36. The medium of claim 32, wherein the code is further operable to:

perform video composition, which processes video by creating a composite view of a set of participants in the conference call.

37. The medium of claim 32, wherein the code is further operable to:

perform audio transcoding that provides audio transcoding or codec translation services that can be used by network devices without forcing the network devices to employ digital signal processing resources to perform audio transcoding on their own.

38. The medium of claim 32, wherein the code is further operable to:

perform media switching that represents an interface between an edge of a network, which is toward the end points, and a core of the network, which is toward other media switches.

39. The medium of claim 32, wherein the code is further operable to:

replicate packets in order to fan out unidirectional video streams such that other media switches participating in the conference call can receive them.