Multiple multicasting of multimedia streams

• US 6,564,262 B1
• Filed: 10/14/1999
• Issued: 05/13/2003
• Est. Priority Date: 09/16/1996
• Status: Expired due to Term

• Current Assignee: Microsoft Technology Licensing LLC (Microsoft Corporation)
• Original Assignee: Microsoft Corporation
• Inventors: Chaddha, Navin
• Primary Examiner(s): CUCHLINSKI JR, WILLIAM A
• Application Number:
  US09/418,139
• Time in Patent Office: 1,307 Days
• Field of Search: 709/203, 709/217, 709/219, 709/227, 709/228, 709/231, 709/235
• US Class Current: 709/231
• CPC Class Codes: H04N 19/507 using conditional replenishment
• CPC Class Codes: H04N 19/51 Motion estimation or motion compensation
• CPC Class Codes: H04N 19/61 in combination with predictive coding
• CPC Class Codes: H04N 19/63 using sub-band based transform, e.g. wavelets
• CPC Class Codes: H04N 19/94 Vector quantisation
• CPC Class Codes: H04N 21/234327 by decomposing into layers, e.g. base layer and one or more enhancement layers
• CPC Class Codes: H04N 21/234363 by altering the spatial resolution, e.g. for clients with a lower screen resolution
• CPC Class Codes: H04N 21/234381 by altering the temporal resolution, e.g. decreasing the frame rate by frame skipping
• CPC Class Codes: H04N 21/2402 Monitoring of the downstream path of the transmission network, e.g. bandwidth available traffic monitoring in data switching networks H04L43/00; monitoring data switching networks utilization H04L43/0876
• CPC Class Codes: H04N 21/25808 Management of client data terminal profiles in network data switching protocols H04L67/303
• 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 21/440227 by decomposing into layers, e.g. base layer and one or more enhancement layers
• CPC Class Codes: H04N 21/4621 Controlling the complexity of the content stream or additional data, e.g. lowering the resolution or bit-rate of the video stream for a mobile client with a small screen arrangements for using the results of monitoring on user's side in broadcast systems H04H60/65; flow control in packet networks H04L47/10
• CPC Class Codes: H04N 21/6405 Multicasting data broadcast and multicast in packet switching networks H04L12/18

Abstract

A method of interactively providing a number of client computers with a dynamically selectable and scalable range of multimedia data over a diverse computer network including local area networks (LANs) wide area networks (WANs) such as the internet. Multimedia data is provided by a server to the client computers includes a base layer and one or more enhancement layers. Enhancement layers can be spatial and/or temporal in nature. Depending on the implementation, the server may also provide information about the multimedia data to the client computers. The server splits the multimedia data for streaming via multiple multicast group (MMG) addresses. Information about the portion of the multimedia data carried by each MMG is broadcasted to the client computers. Armed with the information about the multimedia data, client computers can intelligently join and leave MMGs as needed. In some embodiments, the client computers provide feedback about the usage and/or need for the multimedia data, enabling the server to right-size, e.g., grow and/or prune, the multimedia data for network efficiency. Enhancement layers may also be grown and/or pruned independently of the base layer, i.e., without a corresponding change in the base layer.

Claims

1. In a client computer coupled to a server via a network, a method for receiving data from said server, said data streamed via at least two multicast groups, said method comprising:

receiving said data from said server via said at least two multicast groups;

selecting a first suitable multicast group from said at least two multicast groups, said selected first multicast group associated with a first base layer and a first at least one enhancement layer of said data which best matches a target bandwidth of said client computer;

joining said selected first multicast group;

detecting a change in desired bandwidth of said client computer;

selecting a second suitable multicast group from said at least two multicast groups, said selected second multicast group associated with a second base layer and a second at least one enhancement layer of said data which best matches the changed target bandwidth of said client computer;

joining said selected second multicast group; and

wherein the first multicast group and the second multicast group are joined concurrently.

2. The method of claim 1, wherein said first base layer is different from said second base layer and said first at least one enhancement layer is different from said second at least one enhancement layer.

3. The method of claim 1, wherein said first base layer is similar to said second base layer and said first at least one enhancement layer is different from said second at least one enhancement layer.

4. In a client computer coupled to a server via a network, a computer readable medium having computer executable instructions for receiving data from said server, said data streamed via at least two multicast groups, said computer executable instructions comprising:

receiving said data from said server via said at least two multicast groups;

selecting a first suitable multicast group from said at least two multicast groups, said selected first multicast group associated with a first base layer and a first at least one enhancement layer of said data which best matches a target bandwidth of said client computer;

joining said selected first multicast group;

detecting a change in a desired bandwidth of said client computer;

selecting a second suitable multicast group from said at least two multicast groups, said selected second multicast group associated with a second base layer and a second at least one enhancement layer of said data which best matches the changed target bandwidth of said client computer; and

joining said selected second multicast group while still joined to the first multicast group.

5. The computer readable medium of claim 4, wherein said first base layer is different from said second base layer and said first at least one enhancement layer is different from said second at least one enhancement layer.

6. The computer readable medium of claim 4, wherein said first base layer is similar to said second base layer and said first at least one enhancement layer is different from said second at least one enhancement layer.

7. A method for receiving data at a client computer, comprising:

selecting a first multicast group from at least two multicast groups, wherein the first multicast group includes a first base layer and a first at least one enhancement layer of the data that matches a target bandwidth of the client computer;

joining the first multicast group;

detecting a change in the target bandwidth of the client computer;

selecting a second multicast group from the at least two multicast groups, wherein the second multicast group includes a second base layer and a second at least one enhancement layer of the data that matches the target bandwidth of the client computer; and

joining the second multicast group so that the first multicast group and the second multicast group are joined concurrently.

8. The method of claim 7, wherein said first base layer is different from said second base layer and said first at least one enhancement layer is different from said second at least one enhancement layer.

9. The computer readable medium of claim 7, wherein said first base layer is similar to said second base layer and said first at least one enhancement layer is similar to said second at least one enhancement layer.

10. In a client computer coupled to a server via a network, a computer readable medium having computer executable instructions comprising:

selecting a first multicast group from at least two multicast groups, wherein the first multicast group includes a first base layer and a first at least one enhancement layer of the data that matches a target bandwidth of the client computer;

joining the first multicast group;

detecting a change in the target bandwidth of the client computer;

selecting a second multicast group from the at least two multicast groups, wherein the second multicast group includes a second base layer and a second at least one enhancement layer of the data that matches the target bandwidth of the client computer; and

joining the second multicast group while remaining joined to the first multicast group.

11. The computer readable medium of claim 10, wherein said first base layer is different from said second base layer and said first at least one enhancement layer is different from said second at least one enhancement layer.

12. The computer readable medium of claim 10, wherein said first base layer is similar to said second base layer and said first at least one enhancement layer is similar to said second at least one enhancement layer.