Protecting decrypted compressed content and decrypted decompressed content at a digital rights management client

• US 7,080,410 B2
• Filed: 07/07/2005
• Issued: 07/18/2006
• Est. Priority Date: 06/27/2001
• Status: Expired due to Fees

• Current Assignee: Microsoft Technology Licensing LLC (Microsoft Corporation)
• Original Assignee: Microsoft Corporation
• Inventors: England, Paul, Peinado, Marcus, Sankaranarayan, Mukund
• Primary Examiner(s): Barron, Jr., Gilberto
• Assistant Examiner(s): SANDOVAL, KRISTIN D
• Application Number:
  US11/176,887
• Publication Number:
  US 20050271208A1
• Time in Patent Office: 376 Days
• Field of Search: None
• US Class Current: 726/32
• CPC Class Codes: G06F 21/10 Protecting distributed programs or content, e.g. vending or licensing of copyrighted material protection in video systems or pay television H04N7/16 ; Digital rights management [DRM]

Abstract

Theft of decompressed digital content as the content is being rendered is prevented. A requested slow-down of the rendering of the content is detected. Transfers of relatively large amounts of data are detected. A re-compressor-based requested slow-down of the rendering of the content is detected. A re-compressor re-compressing the content is detected. In each situation, the detected activity is presumably initiated by a content thief attempting to steal the content. In each situation, the detected activity is responded to in a manner designed to frustrate the presumed attempt of the content thief to steal the content.

Claims

1. A method of preventing theft of decompressed digital content as the content is being rendered, the method comprising:

detecting a re-compressor-based requested slow-down of the rendering of the content, wherein the detected requested slow-down is presumably initiated by a content thief attempting to steal and re-compress the content; and

responding to the detected requested slow-down in a manner designed to frustrate the presumed attempt of the content thief to steal and re-compress the content,

wherein detecting comprises sensing X consecutive SEEK or STEP operations.

2. The method of claim 1 wherein detecting comprises consulting all available clocks and determining therefrom if rendering is occurring at less than real-time speed.

3. The method of claim 1 wherein responding comprises ignoring control operations such as SEEK and STEP for Y seconds.

4. The method of claim 1 wherein responding comprises performing a non-responsive action.

5. The method of claim 4 wherein responding comprises performing a non-responsive action selected from a group consisting of rendering at real-time speed, intentionally omitting rendering of frames, and stopping rendering.

6. The method of claim 1 wherein responding comprises providing requested data with a built-in error.

7. The method of claim 6 wherein responding comprises providing requested data with a built-in error which becomes progressively worse.

8. A method of preventing theft of decompressed digital content as the content is being rendered, the method comprising:

detecting a re-compressor-based requested slow-down of the rendering of the content, wherein the detected requested slow-down is presumably initiated by a content thief attempting to steal and re-compress the content; and

responding to the detected requested slow-down in a manner designed to frustrate the presumed attempt of the content thief to steal and re-compress the content,

wherein responding comprises ignoring control operations such as SEEK and STEP for Y seconds.

9. The method of claim 8 wherein detecting comprises sensing X consecutive SEEK or STEP operations.

10. The method of claim 8 wherein detecting comprises consulting all available clocks and determining therefrom if rendering is occurring at less than real-time speed.

11. The method of claim 8 wherein responding comprises performing a non-responsive action.

12. The method of claim 11 wherein responding comprises performing a non-responsive action selected from a group consisting of rendering at real-time speed, intentionally omitting rendering of frames, and stopping rendering.

13. The method of claim 8 wherein responding comprises providing requested data with a built-in error.

14. The method of claim 13 wherein responding comprises providing requested data with a built-in error which becomes progressively worse.

15. A method of preventing theft of decompressed digital content as the content is being rendered, the method comprising:

detecting a re-compressor-based requested slow-down of the rendering of the content, wherein the detected requested slow-down is presumably initiated by a content thief attempting to steal and re-compress the content; and

responding to the detected requested slow-down in a manner designed to frustrate the presumed attempt of the content thief to steal and re-compress the content,

wherein responding comprises providing requested data with a built-in error which becomes progressively worse.

16. The method of claim 15 wherein detecting comprises sensing X consecutive SEEK or STEP operations.

17. The method of claim 15 wherein detecting comprises consulting all available clocks and determining therefrom if rendering is occurring at less than real-time speed.

18. The method of claim 15 wherein responding comprises ignoring control operations such as SEEK and STEP for Y seconds.

19. The method of claim 15 wherein responding comprises performing a non-responsive action.

20. The method of claim 19 wherein responding comprises performing a non-responsive action selected from a group consisting of rendering at real-time speed, intentionally omitting rendering of frames, and stopping rendering.