Methods and systems for encoding and protecting data using digital signature and watermarking techniques

• US 7,107,452 B2
• Filed: 08/22/2005
• Issued: 09/12/2006
• Est. Priority Date: 06/08/1999
• Status: Expired due to Fees

• Current Assignee: PLS IV, LLC (Pretium Partners, LLC)
• Original Assignee: Intertrust Technologies Corporation (Fidelio Acquisition Co LLC)
• Inventors: Boccon-Gibod, Gilles, Serret-Avila, Xavier
• Primary Examiner(s): Peeso, Thomas R.
• Application Number:
  US11/209,238
• Publication Number:
  US 20050283610A1
• Time in Patent Office: 386 Days
• Field of Search: 713/176, 713/182, 713/189
• US Class Current: 713/176
• 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]
• CPC Class Codes: G06T 1/0071 using multiple or alternating watermarks
• CPC Class Codes: G11B 20/00086 Circuits for prevention of unauthorised reproduction or copying, e.g. piracy indicating unauthorised use of record carriers in general G11B23/28; scrambling for television signal recording H04N5/913; network architectures or network protocols for network security H04L63/00; cryptographic mechanisms or cryptographic arrangements for secret or secure communication H04L9/00
• CPC Class Codes: G11B 20/00123 the record carrier being identified by recognising some of its unique characteristics, e.g. a unique defect pattern serving as a physical signature of the record carrier
• CPC Class Codes: G11B 20/00884 involving a watermark, i.e. a barely perceptible transformation of the original data which can nevertheless be recognised by an algorithm
• CPC Class Codes: G11B 20/00898 based on a hash function
• CPC Class Codes: H04L 2209/608 Watermarking
• CPC Class Codes: H04L 9/3236 using cryptographic hash functions
• CPC Class Codes: H04L 9/3247 involving digital signatures
• CPC Class Codes: H04N 1/32144 embedded in the image data, i.e. enclosed or integrated in the image, e.g. watermark, super-imposed logo or stamp
• CPC Class Codes: H04N 1/32208 involving changing the magnitude of selected pixels, e.g. overlay of information or super-imposition H04N1/32219, H04N1/32224 take precedence
• CPC Class Codes: H04N 1/32283 Hashing
• CPC Class Codes: H04N 1/32288 Multiple embedding, e.g. cocktail embedding, or redundant embedding, e.g. repeating the additional information at a plurality of locations in the image
• CPC Class Codes: H04N 1/32293 Repeating the additional information in a regular pattern
• CPC Class Codes: H04N 1/32304 Embedding different sets of additional information
• CPC Class Codes: H04N 1/3232 Robust embedding or watermarking
• CPC Class Codes: H04N 19/00 Methods or arrangements for coding, decoding, compressing or decompressing digital video signals
• CPC Class Codes: H04N 19/467 characterised by the embedded information being invisible, e.g. watermarking
• CPC Class Codes: H04N 2005/91335 the copy protection signal being a watermark
• CPC Class Codes: H04N 21/23892 involving embedding information at multiplex stream level, e.g. embedding a watermark at packet level
• 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 21/8358 : involving watermark protecting executable software by watermarking G06F21/16; image watermarking in general G06T1/0021; watermarks inserted in still images for transmission purposes H04N1/32144; inserting watermarks during video coding H04N19/467
• CPC Class Codes: H04N 2201/3235 : Checking or certification of the authentication information, e.g. by comparison with data stored independently
• CPC Class Codes: H04N 5/913 : for scrambling ; for copy protection
• CPC Class Codes: H04N 7/162 : Authorising the user terminal, e.g. by paying; Registering the use of a subscription channel, e.g. billing

Abstract

Systems and methods are provided for protecting and managing electronic data signals that are registered in accordance with a predefined encoding scheme, while allowing access to unregistered data signals. In one embodiment a relatively hard-to-remove, easy-to-detect, strong watermark is inserted in a data signal. The data signal is divided into a sequence of blocks, and a digital signature for each block is embedded in the signal via a watermark. The data signal is then stored and distributed on, e.g., a compact disc, a DVD, or the like. When a user attempts to access or use a portion of the data signal, the signal is checked for the presence of a watermark containing the digital signature for the desired portion of the signal. If the watermark is found, the digital signature is extracted and used to verify the authenticity of the desired portion of the signal. If the signature-containing watermark is not found, the signal is checked for the presence of the strong watermark. If the strong watermark is found, further use of the signal is inhibited, as the presence of the strong watermark, in combination with the absence or corruption of the signature-containing watermark, provides evidence that the signal has been improperly modified. If, on the other hand, the strong mark is not found, further use of the data signal can be allowed, as the absence of the strong mark indicates that the data signal was never registered with the signature-containing watermark.

Claims

1. A method comprising:

receiving a request to copy an electronic file from a first computer system to a second computer system;

checking the file for the presence of a signature-containing watermark;

if the signature-containing watermark is detected;

retrieving the signature from the watermark,

using the signature to verify the authenticity of at least a portion of the file,

if the verification is successful, granting the request to copy the file to the second computer system, and

if the verification is not successful, denying the request to copy the file to the second computer system; and

if the signature-containing watermark is not detected;

checking the file for the presence of another watermark,

if the other watermark is found, denying the request to copy the file to the second computer system, and

if the other watermark is not found, granting the request to copy the file to the second computer system.

2. The method of claim 1, in which the other watermark is a strong watermark.

3. The method of claim 1, in which the other watermark is relatively more difficult to detect than the signature-containing watermark.

4. A method comprising:

receiving a request to copy an electronic file from a first computer system to a second computer system;

checking the file for the presence of a signature-containing watermark;

if the signature-containing watermark is detected;

retrieving the signature from the watermark,

using the signature to verify the authenticity of at least a portion of the file,

if the verification is successful, granting the request to copy the file to the second computer system, and

if the verification is not successful, denying the request to copy the file to the second computer system; and

if the signature-containing watermark is not detected;

checking the file for the presence of another watermark,

if the other watermark is found, granting the request to copy the file to the second computer system, and

if the other watermark is not found, denying the request to copy the file to the second computer system.

5. The method of claim 4, in which the other watermark is a strong watermark.

6. The method of claim 4, in which the other watermark is relatively more difficult to detect than the signature-containing watermark.

7. A method comprising:

receiving a request to use an electronic file in a predefined manner;

checking the file for the presence of a signature-containing watermark;

if the signature-containing watermark is detected;

retrieving the signature from the watermark,

using the signature to verify the authenticity of at least a portion of the file,

if the verification is successful, granting the request to use the file in the predefined manner, and

if the verification is not successful, denying the request to use the file in the predefined manner; and

if the signature-containing watermark is not detected;

checking the file for the presence of another watermark,

if the other watermark is found, denying the request to use the file in the predefined manner, and

if the other watermark is not found, granting the request to use the file in the predefined manner.

8. The method of claim 7, in which the predefined manner comprises printing contents of the file.

9. The method of claim 7, in which the predefined manner comprises viewing contents of the file.

10. The method of claim 7, in which the predefined manner comprises modifying the file.

11. The method of claim 7, in which the predefined manner comprises one or more of printing, copying, viewing, and modifying the file.

12. The method of claim 7, in which the other watermark is a strong watermark.

13. The method of claim 7, in which the other watermark is relatively more difficult to detect than the signature-containing watermark.

14. The method of claim 13, in which the predefined manner comprises one or more of printing, copying, viewing, and modifying the file.

15. A method comprising:

receiving a request to use an electronic file in a predefined manner;

checking the file for the presence of a signature-containing watermark;

if the signature-containing watermark is detected;

retrieving the signature from the watermark,

using the signature to verify the authenticity of at least a portion of the file,

if the verification is successful, granting the request to use the file in the predefined manner, and

if the verification is not successful, denying the request to use the file in the predefined manner; and

if the signature-containing watermark is not detected;

checking the file for the presence of another watermark,

if the other watermark is found, granting the request to use the file in the predefined manner, and

if the other watermark is not found, denying the request to use the file in the predefined manner.

16. The method of claim 15, in which the predefined manner comprises printing contents of the file.

17. The method of claim 15, in which the predefined manner comprises viewing contents of the file.

18. The method of claim 15, in which the predefined manner comprises modifying the file.

19. The method of claim 15, in which the predefined manner comprises one or more of printing, copying, viewing, and modifying the file.

20. The method of claim 15, in which the other watermark is a strong watermark.

21. The method of claim 15, in which the other watermark is relatively more difficult to detect than the signature-containing watermark.

22. The method of claim 21, in which the predefined manner comprises one or more of printing, copying, viewing, and modifying the file.