MULTIPLE CONTENT PROTECTION SYSTEMS IN A FILE

• US 20100185854A1
• Filed: 06/17/2009
• Published: 07/22/2010
• Est. Priority Date: 01/21/2009
• Status: Active Grant

• Current Assignee: Microsoft Technology Licensing LLC (Microsoft Corporation)
• Original Assignee: Microsoft Corporation
• Inventors: Burns, Quintin Swayne, Simmons, John Carl, Hughes, Robert Kilroy JR.
• Granted Patent: US 8,904,191 B2
• Time in Patent Office: Days
• US Class Current: 713/165
• CPC Class Codes: G06F 12/1408 by using cryptography for digital transmission H04L9/00
• CPC Class Codes: G06F 21/1063 Personalisation
• CPC Class Codes: G06F 2212/1052 Security improvement

Abstract

Supporting a plurality of content protection systems in a single container file. The protection systems share an encryption method which is accessible from a sample encryption box in the file. Each of the protection systems stores, in a protection system header box, information for decrypting the content in accordance with the corresponding protection system. In some embodiments, separate protection system header boxes in the file correspond to each of the protection systems. By using the common encryption method and sharing encryption expressions across the protection systems, the multiple content protection systems are supported in the file without creating additional copies of the content. In some embodiments, aspects of the disclosure extend the International Organization for Standardization (ISO) base media file format to support multiple digital rights management (DRM) systems in the single container file.

Claims

1. A system for extending a media file format to support multiple protection systems in a single container file, said system comprising:

a memory area for storing a file containing encrypted content, a sample encryption box, and a plurality of protection system header boxes each associated with one or more of a plurality of protection systems, wherein the sample encryption box identifies a key used to encrypt the encrypted content, and wherein each of the plurality of protection system header boxes includes metadata for decoding the encrypted content in accordance with one or more of the plurality of protection systems; and

a processor programmed to;

receive, by a service provider, the file from an encoding provider;

select one or more of the plurality of protection systems available to the service provider;

apply the selected protection systems to the content in the received file using the key identified by the sample encryption box; and

store the file with the applied protection systems in the memory area.

2. The system of claim 1, wherein the sample encryption box includes key mapping information to identify the key.

3. The system of claim 1, wherein the sample encryption box includes a key identifier.

4. The system of claim 1, wherein the sample encryption box and the plurality of protection system header boxes enable playback of the file with the plurality of protection systems.

5. The system of claim 1, wherein the file stored in the memory area conforms to the ISO Base Media File Format.

6. The system of claim 1, further comprising means for supporting the plurality of protection systems within a single container file in accordance with the ISO Base Media File Format.

7. The system of claim 1, further comprising means for storing the metadata for the plurality of protection systems in a single container file as an extension to the ISO Base Media File Format.

8. A method comprising:

receiving a file containing content and one or more encryption expressions, said content being encrypted by the encryption expressions;

applying a plurality of protection systems to the content using the encryption expressions from the received file; and

transmitting the file with the content and the applied plurality of protection systems to one or more computing devices for decryption, wherein each of the computing devices decrypts the content using at least one of the applied plurality of protection systems.

9. The method of claim 8, wherein applying the plurality of protection systems to the content comprises adding metadata for each of the plurality of protection systems to the received file, said metadata defining one or more of the following:

a decryption key, a rights object, and license information.

10. The method of claim 8, wherein receiving the file comprises receiving a file containing key mapping information, said content being encrypted using said key mapping information.

11. The method of claim 8, wherein applying the plurality of protection systems to the content comprises:

defining a protection system header box for each of the plurality of protection systems; and

including the defined protection system header box in the received file.

12. The method of claim 11, further comprising embedding license information into the protection system header box.

13. The method of claim 11, further comprising embedding in the protection system header box a reference to license information.

14. The method of claim 8, wherein applying the plurality of protection systems to the content comprises applying the plurality of protection systems to said content without creating another copy of the content.

15. The method of claim 8, wherein receiving the file comprises receiving, from a movie studio, a file corresponding to a movie.

16. One or more computer-readable storage media having computer-executable components, said components comprising:

an interface component that, when executed by at least one processor, causes the at least one processor to receive, by a computing device, a file containing content and one or more encryption expressions, said content being encrypted by the encryption expressions, said content further having a plurality of protection systems applied thereto, said file including metadata for each of the plurality of protection systems;

a detection component that, when executed by at least one processor, causes the at least one processor to select one of the plurality of protection systems supported by the computing device;

a parse component that, when executed by at least one processor, causes the at least one processor to obtain, from the metadata, license information for said one of the plurality of protection systems selected by the detection component; and

a transform component that, when executed by at least one processor, causes the at least one processor to decode the content based on the license information obtained by the parse component and based on the encryption expressions, wherein the interface component presents the decoded content to a user.

17. The computer-readable storage media of claim 16, wherein the transform component decrypts the content.

18. The computer-readable storage media of claim 16, wherein the plurality of protection systems share the same encryption expressions.

19. The computer-readable storage media of claim 16, wherein the content is encoded according to an encryption algorithm, and wherein the plurality of protection systems shares the encryption algorithm.

20. The computer-readable storage media of claim 16, wherein the detection component examines a scheme information box in the file to determine whether the content is encoded with one of the plurality of protection systems.