Video processing in a multi-participant video conference

• US 20060244812A1
• Filed: 04/28/2005
• Published: 11/02/2006
• Est. Priority Date: 04/28/2005
• Status: Active Grant

• Current Assignee: Apple Inc.
• Original Assignee: Apple Inc.
• Inventors: Normile, Jim, Jeong, Hyeonkuk, Abuan, Joe
• Granted Patent: US 7,817,180 B2
• Time in Patent Office: Days
• US Class Current: 348/14.100
• CPC Class Codes: H04N 7/147 Communication arrangements, e.g. identifying the communication as a video-communication, intermediate storage of the signals selecting H04Q
• CPC Class Codes: H04N 7/152 Multipoint control units therefor

Abstract

Some embodiments provide an architecture for establishing multi-participant video conferences. This architecture has a central distributor that receives video images from two or more participants. From the received images, the central distributor generates composite images that the central distributor transmits back to the participants. Each composite image includes a set of sub images, where each sub image belongs to one participant. In some embodiments, the central distributor saves network bandwidth by removing each particular participant'"'"'s image from the composite image that the central distributor sends to the particular participant. In some embodiments, images received from each participant are arranged in the composite in a non-interleaved manner. For instance, in some embodiments, the composite image includes at most one sub-image for each participant, and no two sub-images are interleaved.

Claims

1. A method of distributing video content in a multi-participant video conference, said conference having one central distributor of video content, the method comprising:

a) at the central distributor, receiving participant video images from each participant,

b) generating composite images from the received participant images, and

c) transmitting said composite images to said participants.

2. The method of claim 1, wherein the central distributor includes a data storage, the method further comprising placing each said received participant image in the said data storage in a non-interleaved manner such that each said received participant image is not interleaved with any of the other received participant images.

3. The method of claim 1, the method further comprising:

a) creating a separate composite image for each particular participant, and

b) removing each particular participant'"'"'s received participant image from the particular participant'"'"'s separate composite image before transmitting the separate composite image to the particular participant.

4. The method of claim 3, the method further comprising placing an indicator in place of each particular participant'"'"'s removed image in the particular participant'"'"'s separate composite image.

5. The method of claim 3 further comprising:

at each particular participant'"'"'s location,

a) receiving the composite image transmitted to the particular participant,

b) capturing an image of the particular participant;

c) rendering said participant images contained within the transmitted composite image with said captured images of the particular participant for display.

6. The method of claim 5, wherein the composite image comprises a plurality of sets of pixels, each pixel set has an identifier that identifies the participant image associated with the pixel set, the method further comprising at each participant'"'"'s location, utilizing the identifiers of the pixel sets to identify the participant images contained within the transmitted composite image.

7. The method of claim 1, the method further comprising resizing each of said received participant'"'"'s image before compositing said received images.

8. The method of claim 1, the method further comprising:

a) at the central distributor, saving said received video images before generating said composite images,

b) comparing the received video image of each participant with the saved preceding video image of the particular participant, and

c) utilizing the received video image in generating the composite image if the received video image and the preceding received video image are not identical.

9. A central distributor module for a multi-participant video conference, the central distributor comprising:

a) a set of decoders for decoding video images received from a set of participants in the video conference, and

b) a compositing engine for generating composite video images from the decoded video images,

c) at least one encoder for encoding said composite video images.

10. The central distributor of claim 9 further comprising a set of intermediate buffers for storing a set of decoded video images before the compositing engine generates a composite video image based on the set of decoded video images.

11. The central distributor of claim 9 further comprising a frame rate controller for adjusting a rate at which the compositing engine generates composite video images.

12. The central distributor of claim 9 further comprising a redundancy remover to remove each particular participant'"'"'s image from a composite video image that is to be sent to the particular participant.

13. For receiving and transmitting video content in a multi-participant video conference, an architecture comprising:

a) a focus point module,

b) a set of non-focus point modules,

c) said focus point module for receiving video images from and transmitting composite video images to said set of non-focus point modules, wherein each composite video image is a composite of a plurality of video images received from a plurality of non-focus point modules.

14. The architecture of claim 13, wherein the focus point module eliminates each particular participant'"'"'s image from a composite video image that is sent to the particular participant.

15. A computer readable medium storing a compute program for distributing video content in a multi-participant video conference, said conference having one central distributor of video content, the computer program comprising sets of instructions for:

a) at the central distributor, receiving participant video images from each participant,

b) generating composite images from the received participant images, and

c) transmitting said composite images to said participants.

16. The computer readable medium of claim 15, wherein the central distributor includes a data storage, the computer program further comprising a set of instructions for placing each said received participant image in the said data storage in a non-interleaved manner such that each said received participant image is not interleaved with any of the other received participant images.

17. The computer readable medium of claim 15, wherein the computer program further comprises sets of instructions for:

a) creating a separate composite image for each particular participant, and

b) removing each particular participant'"'"'s received participant image from the particular participant'"'"'s separate composite image before transmitting the separate composite image to the particular participant.

18. The computer readable medium of claim 15, wherein the computer program further comprises set of instructions for resizing each of said received participant'"'"'s image before compositing said received images.