CONTENT PROTECTION INTEROPERABILITY INFRASTRUCTURE

• US 20080086757A1
• Filed: 10/09/2006
• Published: 04/10/2008
• Est. Priority Date: 10/09/2006
• Status: Active Grant

• Current Assignee: Microsoft Technology Licensing LLC (Microsoft Corporation)
• Original Assignee: Microsoft Corporation
• Inventors: Pestoni, Florian
• Granted Patent: US 8,296,569 B2
• Time in Patent Office: Days
• US Class Current: 726/2
• CPC Class Codes: G06F 21/1063 Personalisation
• CPC Class Codes: H04N 21/23473 by pre-encrypting
• CPC Class Codes: H04N 21/4334 Recording operations recording of a television signal H04N5/76; arrangements for recording or accumulating broadcast information or broadcast-related information H04H60/27
• CPC Class Codes: H04N 21/472 End-user interface for requesting content, additional data or services; End-user interface for interacting with content, e.g. for content reservation or setting reminders, for requesting event notification, for manipulating displayed content end-user interfaces for retrieving video data from a database G06F16/739; network services for supporting unicast streaming H04L65/612
• CPC Class Codes: H04N 21/8193 dedicated tools, e.g. video decoder software or IPMP tool
• CPC Class Codes: H04N 21/83555 using a structured language for describing usage rules of the content, e.g. REL
• CPC Class Codes: H04N 21/84 Generation or processing of descriptive data, e.g. content descriptors systems specially adapted for using meta-information in broadcast systems H04H60/73

Abstract

Interoperability of protected content items between computing devices is facilitated by providing content items having a standard representation, and media players having support for the content item representations. The representation of the content item may be limited by a profile as to the elements it contains. The elements allowed in the content item may also be limited.

Claims

1. A method of generating a protected content item for processing by a plurality of computing devices, said protected content item containing at least one protected resource, said method comprising:

defining one or more operations that a computing device is authorized to perform on a resource;

defining a first content protection scheme for permitting authorized operations and for preventing unauthorized operations;

generating a first encrypted resource by encoding the resource as a function of the first content protection scheme;

providing, in a descriptor, information associated with the one or more operations authorized to be performed on the resource;

identifying the first content protection scheme in the descriptor; and

generating a protected content item containing the first encrypted resource and the descriptor.

2. The method of claim 1 further comprising:

defining a second content protection scheme for permitting authorized operations and for preventing unauthorized operations;

generating a second encrypted resource by encoding the resource as a function of the second content protection scheme;

identifying the second content protection scheme in the descriptor; and

wherein the protected content item contains the second encrypted resource and the descriptor identifying the second content protection scheme.

3. The method of claim 1 wherein identifying the first content protection scheme comprises storing an identifier representative of the first content protection scheme in the descriptor.

4. The method of claim 1 wherein identifying the first content protection scheme comprises storing a reference to a source providing the first content protection scheme.

5. The method of claim 1 further comprising defining a profile for generating the protected content item, said profile including a restricted set of elements to be contained in the protected content item relative to the set of elements available in a content item format associated with the protected content item.

6. The method of claim 5 wherein the profile comprises one or more of the following elements:

a descriptor comprising;

exactly one list of tools having a tool description, said tool description comprising either a tool identification or a reference to a source defining the tool; and

exactly one collection of licenses having a description of rights, said description of rights being limited to either a license definition or a reference to a source defining a license; and

a digital item description comprising exactly one tool element having a tool description identifier.

7. The method of claim 6 wherein the profile allows signatures only for the descriptor and the digital item description.

8. The method of claim 1 further comprising encoding resources of the content item with only the first content protection scheme.

9. A computer readable medium having stored thereon a data structure representing a protected content item having a protected resource wherein the protected content item is compatible with a plurality of rendering devices, said structure comprising:

a content item type for identifying a content item format of the content item;

a metadata portion for;

identifying a license associated with the protected resource of the protected content item, said license specifying operations that the plurality of rendering devices is authorized to perform on the protected resource; and

identifying a first content protection scheme for permitting operations authorized by the license and for preventing operations not authorized by the license; and

identifying a location of the protected resource; and

a data portion for containing the protected resource, said protected resource comprising the resource encrypted as a function of the first content protection scheme identified in the metadata portion.

10. The computer readable medium of claim 9 wherein:

the metadata portion further identifies a second content protection scheme for permitting operations authorized by the license and for preventing operations not authorized by the license; and

the data portion contains a second protected resource, said second protected resource comprising the resource encrypted as a function of the second content protection scheme identified in the metadata portion.

11. The computer readable medium of claim 9 wherein the metadata portion identifies the first content protection scheme by storing at least one of the following:

an identifier representative of the first content protection scheme and a reference to a source defining the first content protection scheme.

12. The computer readable medium of claim 9 wherein the protected content item has one or more elements that are restricted as a function of a profile, said profile defining a restricted set of elements to be contained in the protected content item relative to a set of elements available for the content item format associated with the protected content item.

13. The computer readable medium of claim 12 wherein the profile comprises one or more of the following elements:

a descriptor comprising;

exactly one list of tools having a tool description, said tool description comprising either a tool identification or a reference to a source defining the tool; and

exactly one collection of licenses having a description of rights, said description of rights being limited to either a license definition or a reference to a source defining a license; and

a digital item description comprising exactly one tool element having a tool description identifier.

14. The computer readable medium of claim 13 wherein the profile allows signatures only for the descriptor and the digital item description.

15. The computer readable medium of claim 9 wherein the resource comprises digital media content.

16. The computer readable medium of claim 9 wherein resources of the protected content item are encrypted with only the first content protection scheme.

17. A method of processing a protected content item comprising a protected representation of media content at a media player, said protected content item having a descriptor and a first protected resource, said method comprising:

determining a first content protection scheme of the first protected resource from the descriptor;

determining from the descriptor, one or more operations that the media player is authorized to perform on the first protected resource; and

permitting an operation on the first protected resource if the operation is determined to be authorized and the media player supports the first content protection scheme, wherein said permitting comprises;

generating a first resource comprising a plurality of packets from the first protected resource as a function of the determined first content protection scheme;

generating a bitstream from the decrypted resource, said bitstream comprising an unprotected representation of the media content.

18. The method of claim 17 further comprising:

determining a second content protection scheme of a second protected resource of the protected content item from the descriptor when the media player does not support the content protection scheme, said second protected resource containing the same data as the protected resource;

determining from the descriptor, one or more operations that the media player is authorized to perform on the second protected resource; and

permitting an operation on the second protected resource if the operation is determined to be authorized and the media player supports the second content protection scheme, wherein said permitting comprises;

generating a second resource comprising a plurality of packets from the second protected resource as a function of the determined second content protection scheme;

generating a bitstream from the second resource, said bitstream comprising an unprotected representation of the media content.

19. The method of claim 17 further comprising acquiring support for the first content protection scheme of the protected resource at a time other than when the media content is queued for rendering.

20. The method of claim 17 wherein resources of the protected content item are only encrypted with the first content protection scheme.