System and method for secure distribution and evaluation of compressed digital information

• US 7,088,823 B2
• Filed: 01/09/2002
• Issued: 08/08/2006
• Est. Priority Date: 01/09/2002
• Status: Expired due to Fees

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Fetkovich, John E.
• Primary Examiner(s): Revak, Christopher
• Assistant Examiner(s): Moorthy, Aravind K
• Application Number:
  US10/043,369
• Publication Number:
  US 20030131251A1
• Time in Patent Office: 1,672 Days
• Field of Search: 380/255, 380/200, 380/201
• US Class Current: 380/255
• CPC Class Codes: H04N 21/25435 involving characteristics of content or additional data, e.g. video resolution or the amount of advertising
• CPC Class Codes: H04N 21/25833 involving client hardware characteristics, e.g. manufacturer, processing or storage capabilities allocation of resources considering hardware capabilities in multiprogramming arrangements G06F9/5044; allocation of resources considering software capabilities in multiprogramming arrangements G06F9/5055
• CPC Class Codes: H04N 21/4318 by altering the content in the rendering process, e.g. blanking, blurring or masking an image region image enhancement or restoration in general G06T5/00
• CPC Class Codes: H04N 21/44055 by partially decrypting, e.g. decrypting a video stream that has been partially encrypted
• CPC Class Codes: H04N 21/44204 Monitoring of content usage, e.g. the number of times a movie has been viewed, copied or the amount which has been watched monitoring of user activities for profile generation for accessing a video database G06F16/739; protecting generic digital content where the protection is independent of the precise nature of the content G06F21/10; arrangements for monitoring the use made of the broadcast services in broadcast systems H04H60/31
• CPC Class Codes: H04N 21/4627 Rights management associated to the content security in data switching network management H04L41/28; security management or policies for network security H04L63/20; access security in wireless networks H04W12/08
• CPC Class Codes: H04N 21/63345 by transmitting keys key distribution for secret or secure communication H04L9/08; network support of key management H04L63/06
• CPC Class Codes: H04N 7/1675 Providing digital key or authorisation information for generation or regeneration of the scrambling sequence pseudo-random number generators in general G06F7/58

Abstract

A method for controlling access to digital information is performed based on a plurality of decryption keys sent by the information provider. A first type of decryption key instructs a user'"'"'s host system to reproduce the digital information in accordance with a first level of reproduction quality degradation. Additional keys may specify other degradation levels. The quality of the digital information may be degraded based on a time condition or a use condition. Alternatively, only a portion of the information may be made viewable by a user. In order to obtain full and unrestricted access, the user must obtain a type of decryption key from the provider which removes all previous limitations on reproduction quality degradation.

Claims

1. A method for controlling access to digital information, comprising:

storing digital information in an encrypted form on a host system;

reproducing the digital information using a media player application on the host system, said reproducing step including degrading a reproduction quality of the digital information based on at least one of a time condition and a use condition;

storing data on the host system which correlates a first type of decryption key with a first type of reproduction quality degradation performed based on at least one of said time condition and said use condition;

storing said first type of decryption key on the host system; and

comparing said first type of decryption key to the data stored on the host system to identify said first type of reproduction quality degradation,

wherein said reproducing step includes degrading the reproduction quality of the digital information in accordance with the first type of reproduction quality degradation identified in said comparing step.

2. The method of claim 1, further comprising:

storing additional data on the host system which correlates a second type of decryption key with information which indicates that the digital information is to be reproduced without degradation in quality;

storing said second type of decryption key on the host system; and

comparing said second type of decryption key to the additional data stored on the host system,

wherein said reproducing step includes reproducing the digital information on said media player application without degradation in quality based on said additional data comparing step.

3. The method of claim 2, wherein said information which indicates that the digital information is to be reproduced without degradation in quality instructs said media player application to permanently prevent the first type of reproduction quality degradation indicated by said first type of decryption key.

4. The method of claim 1, wherein said reproducing step includes degrading the reproduction quality of the digital information by altering a decompression of the digital information.

5. The method of claim 1, wherein said reproducing step includes degrading the reproduction quality of the digital information by altering a rendering of the digital information.

6. The method of claim 1, wherein the host system is one of a personal computer, a personal digital assistant, and a digital set-top box.

7. The method of claim 1, wherein the media player application includes tamper-resistant software.

8. A method for controlling access to digital information, comprising:

acquiring digital information for reproduction on a host system;

sending the digital information to the host system with a first decryption key, said first decryption key instructing an application program on the host system to degrade the reproduction quality of the digital information based on at least one of a time condition and a use condition.

9. The method of claim 8, further comprising:

receiving information from a user of the host system, said information indicating a desire to have unrestricted access to the digital information; and

sending a second decryption key to the host system, said second decryption key instructing the application program to reproduce the digital information without degradation in quality.

10. The method of claim 9, wherein said second decryption key instructs the application program to reproduce the digital information without degradation.

11. The method of claim 10, further comprising:

defining a pricing structure wherein said second decryption key is priced higher than said first decryption key.

12. The method of claim 8, wherein said first decryption key instructs the application program to degrade the reproduction quality of the digital information by altering a decompression of the digital information.

13. The method of claim 8, wherein said first decryption key instructs the application program to degrade the reproduction quality of the digital information by altering a rendering of the digital information.

14. The method of claim 8, wherein said sending step includes:

sending the application program with the digital information and said first decryption key.

15. The method of claim 14, wherein the application program performs a tamper-resistance function when executed on the host system.

16. The method of claim 14, further comprising:

storing data in the application program which correlates said first decryption key with a first type of reproduction quality degradation performed based on at least one of said time condition and said use condition, wherein the application program performs the first type of reproduction quality degradation when executed on the host system.

17. The method of claim 16, further comprising:

storing additional data in the application program which correlates a second decryption key with information indicating that the digital information is to be reproduced by the application without degradation in quality; and

sending said second decryption key to the host system,

wherein said application program compares said second decryption key to said additional data and then reproduces the digital information without degradation in quality.

18. The method of claim 17, wherein said second decryption key instructs the application program to permanently prevent the reproduction quality degradation of the digital information performed by said first decryption key.

19. The method of claim 16, further comprising:

storing additional data in the application program which correlates a second decryption key with a second type of reproduction quality degradation, said second type of reproduction quality degradation being less severe than the first type of reproduction quality degradation;

sending said second decryption key to the host system,

wherein said application program compares said second decryption key to said additional data and then reproduces the digital information with said second type of reproduction quality degradation.

20. A method for controlling access of digital information, comprising:

storing digital information in an encrypted form on a host system;

reproducing said digital information, using a first decryption key, a first time with a first quality of reproduction, and

reproducing said digital information a second time, using a second decryption key, with a second quality of reproduction, said second quality of reproduction being degraded relative to said first quality of reproduction.

21. A method for controlling access of digital information, comprising:

storing digital information in an encrypted form on a host system;

storing an application program for reproducing the digital information on the host system;

storing a first decryption key on the host system;

activating the application program to reproduce the digital information on the host system, said application program reproducing the digital information based on said first decryption key, said first decryption key controlling said application program to reproduce only a portion of the digital information; and

storing a second decryption key on the host system,

wherein said application program reproduces the digital information a second time based on said second decryption key, said second decryption key controlling said application program to reproduce all of the digital information.