System and method of managing video content streams

• US 8,054,849 B2
• Filed: 05/27/2005
• Issued: 11/08/2011
• Est. Priority Date: 05/27/2005
• Status: Expired due to Fees

• Current Assignee: AT&T Intellectual Property I LP (AT&T, Inc.)
• Original Assignee: AT&T Intellectual Property I LP (AT&T, Inc.)
• Inventors: Nadarajah, Dinesh
• Primary Examiner(s): Moe; Aung S
• Assistant Examiner(s): Chung; Hoon J
• Application Number:
  US11/140,616
• Publication Number:
  US 20060268917A1
• Time in Patent Office: 2,356 Days
• Field of Search: 370/390, 370/432, 370217-221, 370242-244, 725/87, 725/104, 725/139, 725/151, 725/38, 725/57, 725/59, 725/94, 725/97, 725/93, 725/115, 725/146, 714/4.2, 714/4.3, 714/13
• US Class Current: 370/432
• CPC Class Codes: H04L 12/185 with management of multicast group membership
• CPC Class Codes: H04L 65/1101 Session protocols
• 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 65/70 Media network packetisation
• CPC Class Codes: H04L 65/765 intermediate
• CPC Class Codes: H04N 21/26616 for merging a unicast channel into a multicast channel, e.g. in a VOD application, when a client served by unicast channel catches up a multicast channel to save bandwidth data multicast over packet-switching network H04L12/18
• CPC Class Codes: H04N 21/4384 involving operations to reduce the access time, e.g. fast-tuning for reducing channel switching latency
• 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 7/17318 Direct or substantially direct transmission and handling of requests

Abstract

A system and method for managing video content streams are disclosed. The method includes receiving a plurality of multicast video streams at a server and buffering each video stream within a memory at the server. The method also includes generating a multicast video output at the server and a unicast video output at the server.

Claims

1. A method comprising:

receiving, from an acquisition server, a plurality of video streams via multicast at a unicast/multicast video server;

buffering each of the plurality of video streams within a buffer at the unicast/multicast video server;

generating at least one multicast video output at the buffer of the unicast/multicast video server, wherein the buffer is associated with a requested channel, and wherein the at least one multicast video output corresponds to a multicast video stream generated from a multicast replication point of the buffer;

generating at least one unicast video output at the buffer, the at least one unicast video output corresponding to a unicast video stream generated from the multicast video stream;

sending the unicast video output for the requested channel from the unicast/multicast video server to a first set top box of a plurality of set top boxes,

wherein the unicast/multicast video server continues sending the unicast video output for the requested channel to the first set top box until the first set top box has been joined to a multicast group associated with the requested channel; and

sending the multicast video output to the first set top box after the first set top box has been joined to the multicast group.

2. The method of claim 1, further comprising:

sending the at least one multicast video output from the unicast/multicast video server to the plurality of set top boxes.

3. The method of claim 1, wherein the memory comprises a fast channel change buffer operative to receive and buffer a video input, wherein the fast channel change buffer is operative to provide the multicast video output.

4. The method of claim 3, wherein the fast channel change buffer further comprises the multicast replication point operative to provide the multicast video output associated with the multicast group to the plurality of set top boxes including the first set top box.

5. The method of claim 4, wherein the multicast replication point is distinct from a unicast video output point of the fast channel change buffer.

6. The method of claim 5, wherein the multicast replication point is at a beginning portion of the fast channel change buffer and the unicast video output point is at an end portion of the fast channel change buffer.

7. The method of claim 3, wherein the UMV server is further configured to use the fast channel change buffer as an error correction buffer.

8. A method comprising:

sending a channel change request corresponding to a selected channel from a set top box to a first server;

determining, at the set top box, whether the first server is in service;

when the first server is in service, receiving a unicast video output from the first server at the set top box, the unicast video output corresponding to a unicast video stream for the selected channel, wherein the first server continues sending the unicast video output for the selected channel to the set top box until the set top box has been joined to a multicast group associated with the selected channel;

when the first server is in service, receiving a multicast video output corresponding to the selected channel from the first server at the set top box after the set top box has been joined to the multicast group, wherein a buffer within the first server is associated with the selected channel, and wherein the unicast video output and the multicast video output are generated at the buffer; and

when the first server is not in service, transmitting a request for one of a plurality of multicast video streams from the set top box to a remote acquisition server that provides a multicast video stream of the selected channel to the first server when the first server is in service; and

detecting, at the set top box, that the first server has returned to service.

9. The method of claim 8, wherein the unicast video output and the multicast video output are both based on a buffered multicast video stream.

10. The method of claim 8, further comprising:

when the set top box determines that the first server has returned to service, receiving the multicast video output from the first server at the set top box.

11. A server comprising:

a processor;

a non-transitory computer readable storage medium accessible by the processor; and

a computer program embedded within the non-transitory computer readable storage medium, the computer program comprising;

instructions to receive a plurality of video streams via multicast from an acquisition server;

instructions to buffer the plurality of video streams within a plurality of buffers to form a plurality of buffered multicast video streams;

instructions to generate at least one multicast video output from at least a multicast replication point of at least one of the plurality of buffers;

instructions to generate at least one unicast video stream from the at least one of the plurality of buffers, wherein the at least one of the plurality of buffers is associated with a requested channel;

instructions to send the at least one unicast video stream from the server to a set top box for the requested channel;

instructions to continue sending the at least one unicast video stream for the requested channel to the set top box until the set top box has been joined to a multicast group associated with the requested channel; and

instructions to send the at least one multicast video output associated with the multicast group to the set top box, the at least one multicast video output generated from a buffered multicast video stream of the plurality of buffered multicast video streams associated with the requested channel.

12. The server of claim 11, wherein the computer program further comprises instructions to receive a channel change request from the set top box.

13. The server of claim 11, further comprising:

a fast channel change buffer operative to receive and buffer a video input, wherein the fast channel change buffer is operative to provide the buffered multicast video stream.

14. The server of claim 13, wherein the fast channel change buffer further comprises a multicast replication point operative to send the at least one multicast video output associated with the multicast group to a plurality of set top boxes including the set top box.

15. A set top box, comprising:

a processor;

a non-transitory computer readable storage medium accessible to the processor; and

a computer program embedded within the non-transitory computer readable storage medium, the computer program comprising;

instructions to receive a channel change request corresponding to a requested channel;

instructions to determine whether a first server is in service;

instructions to transmit an output to the first server when the first server is in service, wherein the output includes the channel change request;

instructions to continue receiving a unicast video output associated with the requested channel while the first server joins the set top box to a multicast group associated with the requested channel when the first server is in service;

instructions to receive a multicast video output from the first server after the first server joins the set top box to the multicast group when the first server is in service, wherein a buffer within the first server is associated with the selected channel, and wherein the unicast video output and the multicast video output are generated at the buffer;

instructions to transmit a request to receive the multicast video output from an acquisition server when the first server is not in service, wherein the remote acquisition server provides the multicast video output of the requested channel to the first channel when the first channel is in service; and

instructions to sense when the first server has returned to service.

16. The set top box of claim 15, wherein the computer program further comprises:

instructions to receive the multicast video output from the first server in response to sensing that the first server has returned to service.