Variable Rate Media Delivery System

• US 20100235438A1
• Filed: 03/12/2010
• Published: 09/16/2010
• Est. Priority Date: 11/24/2008
• Status: Active Grant

• Current Assignee: Juniper Networks Incorporated
• Original Assignee: Juniper Networks Incorporated
• Inventors: Kohil, Jaspal, Narayanan, Kumar, Narayanan, Shivakumar Karathozuvu, Mukundan, Sunil, Visharam, Zubair, Sundarrajan, Prabakar
• Granted Patent: US 8,190,674 B2
• Time in Patent Office: Days
• US Class Current: 709/203
• CPC Class Codes: H04L 65/60 Network streaming of media packets
• CPC Class Codes: H04L 65/612 for unicast
• CPC Class Codes: H04L 65/752 adapting media to network capabilities
• CPC Class Codes: H04L 65/762 at the source reformatting of additional data in video distribution servers H04N21/2355
• CPC Class Codes: H04L 65/80 Responding to QoS
• CPC Class Codes: H04N 21/23439 for generating different versions
• CPC Class Codes: H04N 21/23805 Controlling the feeding rate to the network, e.g. by controlling the video pump
• CPC Class Codes: H04N 21/2407 Monitoring of transmitted content, e.g. distribution time, number of downloads arrangements for monitoring programmes for broadcast or for distribution combined with broadcast H04H20/14
• CPC Class Codes: H04N 21/8456 by decomposing the content in the time domain, e.g. in time segments

Abstract

A method and apparatus for delivering variable bit rate media files delivers media files to client systems. The media server can dynamically detect when a client can accept a different bit rate version of a media content. The media server can smoothly switch between different bit rate versions of the media content as it delivers the media content to client systems. A client system can also request different bit rate versions of a media content while it is playing the media content.

Claims

1. A method for dynamically delivering variable bit rate media content across a network to a plurality of client systems, comprising:

receiving, at a server, a request for a media content from a client system;

delivering, by the server, portions of the requested media content to the client system that are encoded for a first bit rate;

determining, at the server, that delivery of the portions of the requested media content that are encoded for the first bit rate can be changed to delivery of portions of the requested media content that are encoded for a second bit rate;

upon the determination that delivery of the portions of the requested media content that are encoded for the first bit rate can be changed to delivery of portions of the requested media content that are encoded for a second bit rate, the delivering step stops delivering the portions of the requested media content to the client system that are encoded for the first bit rate and begins delivering portions of the requested media content to the client system that are encoded for the second bit rate.

2. The method of claim 1, further comprising:

determining, at the server, that available bandwidth between the server and the client system has changed;

wherein the available bandwidth determining step notifies the delivery determination step that the available bandwidth between the server and the client system has changed.

3. The method of claim 1, wherein the client system specifies the second bit rate.

4. The method of claim 3, further comprising:

receiving, at the client system, available bit rates and features for the requested media content from the server;

wherein the client system selects the second bit rate from the received available bit rates.

5. The method of claim 1, further comprising:

storing a plurality of media content files on at least one storage device in communication with the server;

wherein the at least one storage device contains the portions of the requested media content that are encoded for the first bit rate and the portions of the requested media content that are encoded for the second bit rate.

6. The method of claim 1, further comprising:

encoding the portions of the requested media content that are encoded for the second bit rate as the portions are being delivered to the client system.

7. The method of claim 1, wherein the delivering step begins delivering the portions of the requested media content that are encoded for the second bit rate from the point in the requested media content where delivery of the portions of the requested media content that are encoded for the first bit rate was stopped.

8. The method of claim 7, wherein the delivering step refers to an index to find a media frame in the requested media content that is encoded for the second bit rate that is associated with a media frame where delivery of the portions of the requested media content that are encoded for the first bit rate was stopped, and wherein the delivering step begins delivering the portions of the requested media content that are encoded for the second bit rate from the associated media frame in the requested media content that is encoded for the second bit rate.

9. The method of claim 7, wherein the delivering step stops delivery of the portions of the requested media content that are encoded for the first bit rate at the end of a media portion chunk of the requested media content that is encoded for the first bit rate and begins delivering the portions of the requested media content that are encoded for the second bit rate from the beginning of a media portion chunk in the requested media content that is encoded for the second bit rate, the beginning of the media portion chunk in the requested media content that is encoded for the second bit rate is sequential in time with the end of the media portion chunk of the requested media content that is encoded for the first bit rate.

10. The method of claim 1, further comprising:

delivering alternate content as part of the portions of the requested media content as the portions of the requested media content are being delivered to the client system.

11. The method of claim 1, wherein the delivering step delivers the portions of the requested media content that are encoded for the first bit rate as the portions of the requested media content that are encoded for the first bit rate are received from an origin server.

12. The method of claim 11, wherein the requested media content that are encoded for the first bit rate received from the origin server are queued for encoding by the server into the second bit rate.

13. The method of claim 1, wherein the requested media content are audio content.

14. The method of claim 1, wherein the requested media content are video content.

15. An apparatus for dynamically delivering variable bit rate media across a network to a plurality of client systems, comprising:

a media delivery request receiver, on a server, that receives a request for media content from a client system;

a media content delivery subsystem, on the server, that delivers portions of a requested media content to the client system that are encoded for a first bit rate;

a bit rate transition determination subsystem, on the server, that determines that delivery of the portions of the requested media content that are encoded for the first bit rate can be changed to delivery of portions of the requested media content that are encoded for a second bit rate;

upon the determination that delivery of the portions of the requested media content that are encoded for the first bit rate can be changed to delivery of portions of the requested media content that are encoded for a second bit rate, the media content delivery subsystem stops delivering the portions of the requested media content to the client system that are encoded for the first bit rate and begins delivering portions of the requested media content to the client system that are encoded for the second bit rate.

16. The apparatus of claim 15, further comprising:

a bandwidth determination subsystem, on the server, that determines that available bandwidth between the server and the client system has changed;

wherein the bandwidth determination subsystem notifies the bit rate transition determination subsystem that the available bandwidth between the server and the client system has changed.

17. The apparatus of claim 15, wherein the client system specifies the second bit rate.

18. The apparatus of claim 17, further comprising:

a media content description receiver, on the client system, that receives available bit rates and features for the requested media content from the server;

wherein the client system selects the second bit rate from the received available bit rates.

19. The apparatus of claim 15, further comprising:

at least one storage device in communication with the server storing a plurality of media content files;

wherein the at least one storage device contains the portions of the requested media content that are encoded for the first bit rate and the portions of the requested media content that are encoded for the second bit rate.

20. The apparatus of claim 15, wherein the media content delivery subsystem encodes the portions of the requested media content that are encoded for the second bit rate as the portions are being delivered to the client system.

21. The apparatus of claim 15, wherein the media content delivery subsystem begins delivering the portions of the requested media content that are encoded for the second bit rate from the point in the requested media content where delivery of the portions of the requested media content that are encoded for the first bit rate was stopped.

22. The apparatus of claim 21, wherein the media content delivery subsystem refers to an index to find a media frame in the requested media content that is encoded for the second bit rate that is associated with a media frame where delivery of the portions of the requested media content that are encoded for the first bit rate was stopped, and wherein the media content delivery subsystem begins delivering the portions of the requested media content that are encoded for the second bit rate from the associated media frame in the requested media content that is encoded for the second bit rate.

23. The apparatus of claim 21, wherein the media content delivery subsystem stops delivery of the portions of the requested media content that are encoded for the first bit rate at the end of a media portion chunk of the requested media content that is encoded for the first bit rate and begins delivering the portions of the requested media content that are encoded for the second bit rate from the beginning of a media portion chunk in the requested media content that is encoded for the second bit rate, the beginning of the media portion chunk in the requested media content that is encoded for the second bit rate is sequential in time with the end of the media portion chunk of the requested media content that is encoded for the first bit rate.

24. The apparatus of claim 15, wherein the media content delivery subsystem delivers alternate content as part of the portions of the requested media content as the portions of the requested media content are being delivered to the client system.

25. The apparatus of claim 15, wherein the media content delivery subsystem delivers the portions of the requested media content that are encoded for the first bit rate as the portions of the requested media content that are encoded for the first bit rate are received from an origin server.

26. The apparatus of claim 25, wherein the requested media content that are encoded for the first bit rate received from the origin server are queued for encoding by the server into the second bit rate.

27. The apparatus of claim 15, wherein the requested media content are audio content.

28. The apparatus of claim 15, wherein the requested media content are video content.