Session Description Message Extensions

• US 20070011345A1
• Filed: 07/21/2006
• Published: 01/11/2007
• Est. Priority Date: 04/30/2004
• Status: Active Grant

• Current Assignee: Microsoft Technology Licensing LLC (Microsoft Corporation)
• Original Assignee: Microsoft Corporation
• Inventors: Klemets, Anders
• Granted Patent: US 7,783,772 B2
• Time in Patent Office: Days
• US Class Current: 709/231
• CPC Class Codes: H04L 65/1101 Session protocols
• CPC Class Codes: H04L 65/70 Media network packetisation
• CPC Class Codes: H04N 21/6125 involving transmission via Internet transmission by internet of broadcast information H04H60/82
• CPC Class Codes: H04N 21/6332 directed to client
• CPC Class Codes: H04N 21/6437 Real-time Transport Protocol [RTP]
• CPC Class Codes: H04N 7/17336 Handling of requests in head-ends

Abstract

Session description message extensions include information describing a multimedia presentation or a single media presentation. The session description message is typically sent from one device to another device to which the multimedia or single media presentation will be streamed. Several extensions are described that extend the information that can be included in the session description message.

Claims

1. One or more computer readable media having stored thereon a plurality of instructions for generating a session description message that describes properties of a multimedia presentation to be streamed to a client device, the plurality of instructions, when executed by one or more processors, causing the one or more processors to:

access an ASF file header of the multimedia presentation;

identify a subset of a plurality of objects of the ASF file header;

generate, for each object in the subset of the plurality of objects, a different one of a plurality of extensions for the session description that are separate from the ASF file header; and

for each object in the subset of the plurality of objects;

retrieve one or more parameters from the object, and

use the retrieved parameters as the parameters for one of the plurality of extensions.

2. One or more computer readable media as recited in claim 1, wherein one of the plurality of extensions comprises a mutual exclusivity extension that specifies which of a plurality of media streams of the multimedia presentation are mutually exclusive.

3. One or more computer readable media as recited in claim 1, wherein one of the plurality of extensions comprises a marker extension specifies an index into the multimedia presentation.

4. One or more computer readable media as recited in claim 1, wherein one of the plurality of extensions comprises a script command extension that specifies data that is to be presented during playback of the multimedia presentation.

5. One or more computer readable media as recited in claim 1, wherein one of the plurality of extensions comprises a caching information extension that specifies information about caching of the multimedia presentation.

6. One or more computer readable media as recited in claim 1, wherein one of the plurality of extensions comprises an encapsulation extension that specifies codec parameters for one or more of a plurality of different codecs.

7. One or more computer readable media as recited in claim 1, wherein one of the plurality of extensions comprises a bandwidth sharing extension that specifies media streams of a plurality of media streams of the multimedia presentation that share bandwidth.

8. One or more computer readable media as recited in claim 1, wherein one of the plurality of extensions comprises a stream prioritization extension that specifies which of a plurality of media streams of the multimedia presentation should have priority over which other of the plurality of media streams.

9. One or more computer readable media having stored thereon a plurality of instructions that, when executed by one or more processors, causes the one or more processors to:

generate a session description message that describes properties of a multimedia presentation to be streamed to a client device, the multimedia presentation having a plurality of media streams, and the session description message having a caching information extension that is separate from any ASF file header of the multimedia presentation and that specifies information about caching of the multimedia presentation; and

include, as part of data streamed to the client device, the session description message.

10. One or more computer readable media as recited in claim 9, wherein the session description message is a Session Description Protocol (SDP) message.

11. One or more computer readable media as recited in claim 9, wherein the instructions that cause the one or more processors to generate the session description message further cause the one or more processors to:

identify an object of an ASF file header of the multimedia presentation;

retrieve one or more parameters from the object; and

analyze the retrieved one or more parameters to determine the parameters for the caching information extension.

12. One or more computer readable media as recited in claim 9, wherein the information about caching of the multimedia presentation comprises information specifying whether the client device is allowed to cache the multimedia presentation.

13. One or more computer readable media as recited in claim 9, wherein the information about caching of the multimedia presentation comprises information specifying whether the client device is allowed to rebroadcast the multimedia presentation.

14. One or more computer readable media having stored thereon a plurality of instructions that, when executed by one or more processors, causes the one or more processors to:

generate a session description message that describes properties of a multimedia presentation to be streamed to a client device, the multimedia presentation having a plurality of media streams, and the session description message having an encapsulation extension that is separate from any ASF file header of the multimedia presentation and that specifies codec parameters for one or more of a plurality of different codecs; and

include, as part of data streamed to the client device, the session description message.

15. One or more computer readable media as recited in claim 14, wherein the session description message includes a plurality of encapsulation extensions, each of the plurality of encapsulation extensions having the same syntax but being for a different one of the plurality of different codecs.

16. One or more computer readable media as recited in claim 14, wherein the instructions that cause the one or more processors to generate the session description message further cause the one or more processors to:

identify an object of an ASF file header of the multimedia presentation;

retrieve one or more parameters from the object; and

analyze the retrieved one or more parameters to determine the parameters for the encapsulation extension.

17. One or more computer readable media as recited in claim 14, wherein the codec parameters include an identifier of a type of a media stream of the multimedia presentation that is to be decoded by the one or more codecs.

18. One or more computer readable media as recited in claim 14, wherein the codec parameters include an indication of whether a media stream of the multimedia presentation that is to be decoded by the one or more codecs uses temporal compression.

19. One or more computer readable media as recited in claim 14, wherein the codec parameters include initialization data for the one or more codecs.

20. One or more computer readable media as recited in claim 19, wherein the codec parameters include a format of the initialization data in the session description message.