Electronic watermark system electronic information distribution system and image filing apparatus

• US 6,425,081 B1
• Filed: 08/14/1998
• Issued: 07/23/2002
• Est. Priority Date: 08/20/1997
• Status: Expired due to Term

• Current Assignee: Canon Ayutthaya Limited (Canon Inc.)
• Original Assignee: Canon Ayutthaya Limited (Canon Inc.)
• Inventors: Iwamura, Keiichi
• Primary Examiner(s): Barron, Gilberto
• Assistant Examiner(s): Meislahn, Douglas J.
• Application Number:
  US09/134,516
• Time in Patent Office: 1,439 Days
• Field of Search: 713/176, 705/58
• US Class Current: 713/176
• CPC Class Codes: G06T 1/0021 Image watermarking
• CPC Class Codes: H04L 2209/30 Compression, e.g. Merkle-Damgard construction
• CPC Class Codes: H04L 2209/42 Anonymization, e.g. involving pseudonyms
• CPC Class Codes: H04L 2209/608 Watermarking
• CPC Class Codes: H04L 2463/103 applying security measure for protecting copyright
• CPC Class Codes: H04L 63/0428 wherein the data content is protected, e.g. by encrypting or encapsulating the payload
• CPC Class Codes: H04L 63/0823 using certificates cryptographic mechanisms or cryptographic arrangements for entity authentication involving certificates H04L9/3263
• CPC Class Codes: H04L 63/123 received data contents, e.g. message integrity
• CPC Class Codes: H04L 9/3247 involving digital signatures
• CPC Class Codes: H04L 9/3263 involving certificates, e.g. public key certificate [PKC] or attribute certificate [AC]; Public key infrastructure [PKI] arrangements network architectures or network communication protocols for supporting authentication of entities using certificates in a packet data network H04L63/0823
• 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 1/32272 Encryption or ciphering
• CPC Class Codes: H04N 1/32304 Embedding different sets of additional information
• CPC Class Codes: H04N 2201/3233 of authentication information, e.g. digital signature, watermark
• CPC Class Codes: H04N 2201/327 which are undetectable to the naked eye, e.g. embedded codes
• CPC Class Codes: H04N 2201/3281 Encryption; Ciphering

Abstract

Disclosed is an electronic watermark method, used for a network, comprising a plurality of entities, wherein provided weparately are an entity for embedding an electronic watermark in encrypted data that are exchanged by said plurality of entities, and an entity for performing an encryption process and a corresponding decryption process.

Claims

1. An electronic watermark method used for a network system that includes a plurality of entities, wherein for the exchange of digital information by at least a first entity and a second entity of the plurality of entities,

the first entity embeds an electronic watermark in the digital information, performs a first encryption process for the digital information, and transmits the resultant digital information to the second entity,

the second entity embeds a second electronic watermark in the digital information received from the first entity, performs a second encryption process for the digital information, obtains a value by transforming the resultant digital information using a one-way compression function, and transmits the value and the resultant digital information to the first entity, and

the first entity converts the digital information received from the second entity using the one-way compression function and, in accordance with whether the thus obtained value matches the value received from the second entity, performs a first decoding process related to the first encryption process for the digital information.

2. An electronic watermark method according to claim 1 wherein said electronic watermark embedding process performed by the first entity is a process for embedding information concerning the second entity.

3. An electronic watermark method according to claim 1 wherein said electronic watermark embedding process performed by the first entity is a process for embedding information concerning digital information to be transmitted.

4. An electronic watermark method according to claim 1 wherein said electronic watermark embedding process performed by the second entity is a process for embedding information that only the second entity is capable of creating.

5. A method according to claim 1, wherein the first entity transmits to the second entity the digital information on which said first decoding process has been performed, and the second entity performs a second decoding process for the digital information received from the first entity on which said first decoding process has been performed.

6. A method according to claim 1 wherein the one-way compression function is a hash function.

7. An electronic watermark system for a network system that includes a plurality of entities, wherein for the exchange of digital information by at least a first entity and a second entity of the plurality of entities,

the first entity embeds an electronic watermark in the digital information, performs a first encryption process for the digital information, and transmits the resultant digital information to the second entity,

the second entity embeds a second electronic watermark in the digital information received from the first entity, performs a second encryption process for the digital information, obtains a value by transforming the resultant digital information using a one-way compression function, and transmits the value and the resultant digital information to the first entity, and

the first entity converts the digital information received from the second entity using the one-way compression function and, in accordance with whether the thus obtained value matches the value received from the second entity, performs a first decoding process related to the first encryption process for the digital information.

8. A computer-readable medium containing program codes for an electronic watermark method for a network system that includes a plurality of entities, wherein for the exchange of digital information by at least a first entity and a second entity of the plurality of entities,

the first entity embeds an electronic watermark in the digital information, performs a first encryption process for the digital information, and transmits the resultant digital information to the second entity,

the second entity embeds a second electronic watermark in the digital information received from the first entity, performs a second encryption process for the digital information, obtains a value by transforming the resultant digital information using a one-way compression function, and transmits the value and the resultant digital information to the first entity, and

the first entity converts the digital information received from the second entity using the one-way compression function and, in accordance with whether the thus obtained value matches the value received from the second entity, performs a first decoding process related to the first encryption process for the digital information.

9. A computer-readable program comprising program codes for an electronic watermark method for a network system that includes a plurality of entities, wherein for the exchange of digital information by at least a first entity and a second entity of the plurality of entities,

the first entity embeds an electronic watermark in the digital information, performs a first encryption process for the digital information, and transmits the resultant digital information to the second entity,

the second entity embeds a second electronic watermark in the digital information received from the first entity, performs a second encryption process for the digital information, obtains a value by transforming the resultant digital information using a one-way compression function, and transmits the value and the resultant digital information to the first entity, and

the first entity converts the digital information received from the second entity using the one-way compression function and, in accordance with whether the thus obtained value matches the value received from the second entity, performs a first decoding process related to the first encryption process for the digital information.