Integration of audio conference bridge with video multipoint control unit

• US 20080165245A1
• Filed: 01/10/2007
• Published: 07/10/2008
• Est. Priority Date: 01/10/2007
• Status: Active Grant

• Current Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Original Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Inventors: Taylor, Stuart Asbury, Baird, Randall B., Sarkar, Shantanu
• Granted Patent: US 8,149,261 B2
• Time in Patent Office: Days
• US Class Current: 348/14.09
• CPC Class Codes: H04L 12/1827 Network arrangements for conference optimisation or adaptation
• CPC Class Codes: H04L 65/4038 with floor control
• CPC Class Codes: H04L 65/4053 without floor control
• CPC Class Codes: H04L 65/70 Media network packetisation
• CPC Class Codes: H04M 3/569 using the instant speaker's algorithm speech detection per se G10L25/78
• CPC Class Codes: H04N 7/152 Multipoint control units therefor

Abstract

In one embodiment, a system includes a video multipoint control unit (MCU) and an audio conferencing bridge, the audio conferencing bridge being operable to receive audio streams from audio-only and video endpoints, and to negotiate video sessions between each of the video endpoints and the video MCU. In response to detecting when one of the video endpoints is an active speaker, the audio conferencing bridge transmitting a dummy audio stream over a dummy audio channel from the audio conferencing bridge to the video MCU. The dummy audio stream causes the video MCU to switch an image in a video output stream. It is emphasized that this abstract is provided to comply with the rules requiring an abstract that will allow a searcher or other reader to quickly ascertain the subject matter of the technical disclosure.

Claims

1. A method comprising:

detecting, by an audio conferencing bridge, an attempt by an endpoint to establish a plurality of multimedia sessions; and

negotiating a dummy session between the audio bridge and the video MCU, the dummy session for indicating to the video MCU when the endpoint is an active speaker in a conference session.

2. The method of claim 1 wherein the endpoint is operable to send and receive a video session.

3. The method of claim 1 further comprising negotiating, by the audio conferencing bridge, a video session between the endpoint and the video MCU.

4. The method of claim 1 further comprising establishing an audio session between the endpoint and the audio conferencing bridge.

5. The method of claim 1 further comprising sending a generic audio clip to the video MCU in response to the endpoint becoming the active speaker.

6. The method of claim 3 wherein the generic audio clip comprises audible speech.

7. The method of claim 5 further comprising halting the sending of the generic audio clip to the video MCU when the endpoint is no longer the active speaker.

8. The method of claim 5 wherein the generic audio clip comprises a plurality of packets, and further comprising attaching an RTP header that includes a sequence number and a timestamp to each packet of the generic audio clip.

9. The method of claim 1 wherein the active speaker comprises one of a plurality of loudest speakers in the conference session.

10. A method comprising:

receiving audio media streams from a plurality of endpoints participating in a conference session, the endpoints including audio-only endpoints and video endpoints;

receiving control signals from the plurality of endpoints;

establishing a video media channel between each of the video endpoints and a video multipoint control unit (MCU);

detecting that a first video endpoint is an active speaker in the conference session;

sending a pre-recorded audio clip to the video MCU over an audio channel associated with the first video endpoint, the video MCU sending an image of a user of the first video endpoint to one or more of the video endpoints in response to the pre-recorded audio clip.

11. The method of claim 10 wherein the pre-recorded audio clip comprises audible speech.

12. The method of claim 10 further comprising:

detecting that the first video endpoint is no longer the active speaker; and

halting the sending of the pre-recorded audio clip to the video MCU.

13. The method of claim 10 wherein the pre-recorded audio clip comprises a plurality of packets, and further comprising attaching an RTP header that includes a sequence number and a timestamp to each packet of the pre-recorded audio clip.

14. The method of claim 10 wherein the control signals comprise dual tone, multi-frequency (DTMF) commands.

15. The method of claim 10 further comprising mixing the audio media streams to produce one or more mixed audio output streams.

16. The method of claim 15 further comprising delaying the one or more mixed audio output streams.

17. The method of claim 16 further comprising computing a half round-trip delay over the audio channel, the one or more mixed audio output streams being delayed in correspondence with the half round-trip delay plus an additional delay corresponding to a mixing delay between the audio conferencing bridge and the video MCU.

18. Logic encoded in one or more media for execution and when executed is operable to:

detect when a first video endpoint becomes an active speaker in a conference session among one or more audio-only endpoints and a plurality of video endpoints which includes the first video endpoint;

send a dummy audio stream to a video bridge via an audio channel that corresponds to the first video endpoint, the dummy audio stream causing the video bridge to include an image received from the first video endpoint in an output video stream;

detect when the first video endpoint is no longer the active speaker; and

halt the sending of the dummy audio stream.

19. The logic of claim 18 wherein the logic, when executed, is further operable to:

receive audio streams from the one or more audio-only endpoints and the video endpoints; and

mix the audio streams into one or more output audio streams.

20. The logic of claim 18 wherein the logic, when executed, is further operable to:

receive first command signals from the one or more audio-only endpoints and second command signals from the video endpoints, the first and second command signals being in a first format;

translate the second command signals into a second format compatible with the video bridge; and

send the second command signals in the second format to the video bridge.

21. The logic of claim 20 wherein the first and second command signals comprise dual tone, multi-frequency (DTMF) keypad sequences.

22. The logic of claim 18 wherein the logic, when executed, is further operable to delay the one or more mixed audio output streams.

23. A system comprising:

one or more processors; and

a memory comprising one or more instructions executable at the processors, the processors operable when executing the instructions to;

receive audio input streams received from audio endpoints and audio/video (A/V) endpoints;

mix the audio packet streams to produce one or more audio output streams for transmission to the audio and A/V endpoints;

establish a video channel between each of the A/V endpoints and a video multipoint control unit (MCU);

detect that a first A/V endpoint is an active speaker;

send a dummy audio packet stream to the video MCU over a dummy audio channel associated with the first video endpoint, the video MCU switching a video output stream sent to the A/V endpoints in response to the dummy audio packet stream.

24. The system of claim 23 wherein the one or more processors is further operable to halt sending of the dummy audio packet stream in response to detecting that the first A/V endpoint is no longer the active speaker.

25. A system comprising:

a video multipoint control unit (MCU); and

an audio conferencing bridge operable to receive audio streams from audio-only and video endpoints participating in a conference session, and to negotiate a video sessions between each of the video endpoints and the video MCU, the audio conferencing bridge also being operable to receive media command signals in a first format from the audio-only and audio/video (A/V) endpoints, the audio conferencing bridge translating the media command signals received in the first format from the A/V endpoints into a second format for transmission to the video MCU, the audio conferencing bridge being further operable to detect when one of the A/V endpoints is an active speaker in the conference session and, in response, transmit a dummy audio stream over a dummy audio channel from the audio conferencing bridge to the video MCU, the dummy audio stream causing the video MCU to switch an image in a video output stream.

26. The system of claim 25 wherein the audio conferencing bridge is further operable to:

mix the audio streams to produce one or more audio output streams; and

delay the one or more audio output streams to synchronize with the video output stream.

27. The system of claim 25 wherein the audio conferencing bridge is further operable to stop transmitting the dummy audio stream over the dummy audio channel when the audio conferencing bridge detects that the one of the A/V endpoints is no longer the active speaker.

28. A method comprising:

detecting, by an audio conferencing bridge, an attempt by an audio/video (A/V) endpoint to establish a video session;

negotiating, by the audio conferencing bridge, a session between the A/V endpoint and a video multipoint control unit (MCU); and

negotiating a dummy session between the audio bridge and the video MCU, the dummy session for indicating to the video MCU when the A/V endpoint is an active speaker in a conference session.

29. The method of claim 28 further comprising establishing an audio session between the A/V endpoint and the audio conferencing bridge.

30. The method of claim 28 further comprising sending a generic audio clip to the video MCU in response to the A/V endpoint becoming the active speaker.

31. The method of claim 30 wherein the generic audio clip comprises audible speech.

32. The method of claim 30 further comprising halting the sending of the generic audio clip to the video MCU when the A/V endpoint is no longer the active speaker.