Authentication of Physical and Electronic Media Objects Using Digital Watermarks

• US 20110091066A1
• Filed: 10/26/2010
• Published: 04/21/2011
• Est. Priority Date: 04/17/2000
• Status: Active Grant

• Current Assignee: Adnan M. Alattar
• Original Assignee: Adnan M. Alattar
• Inventors: Alattar, Adnan M.
• Granted Patent: US 8,175,329 B2
• Time in Patent Office: Days
• US Class Current: 382/100
• CPC Class Codes: G06T 1/0028 Adaptive watermarking, e.g. Human Visual System [HVS]-based watermarking
• 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 1/32283 Hashing
• CPC Class Codes: H04N 2201/3205 of identification information, e.g. name or ID code H04N2201/3209 takes precedence
• CPC Class Codes: H04N 2201/3233 of authentication information, e.g. digital signature, watermark
• CPC Class Codes: H04N 2201/3236 Details of authentication information generation
• CPC Class Codes: H04N 2201/327 which are undetectable to the naked eye, e.g. embedded codes

Abstract

Digital watermark methods for encoding auxiliary data into a host signal are used to authenticate physical and electronic objects. One such method computes a content specific message dependent on the host signal, encodes the content specific message into a watermark signal, and embeds the watermark in the host signal such that the watermark signal is substantially imperceptible in the host signal. One specific implementation embeds data representing salient features of the host signal into the watermark. For example, for photo IDs, the method embeds the spatial location of salient features of the photo into the watermark. Another implementation computes a semi-sensitive hash of the host signal, such as a low pass filtering of the signal, and embeds the hash into the watermark. The watermark signal may be content dependent by making the watermark key dependent on some attribute of the signal in which the watermark is embedded. Another approach is to make the watermark key dependent on a user or an attribute of the user. Yet another approach is to use multiple watermark components and multiple watermark detection stages that help identify and screen out invalid watermark signals. Another digital watermarking method for authenticating a media object transforms a media signal to a frequency domain comprising an array of frequency coefficients. It selects a first set of frequency coefficients, and alters the selected first set of frequency coefficients so that values of the coefficients in the set correspond to a pattern. The pattern of the media signal is authenticated by comparing a pattern of the values of the frequency coefficients in the set with an expected pattern.

Claims

1. A method for encoding auxiliary data into a host signal, the method employing a device having a processor configured to perform one or more acts of the method, the method comprising:

providing a plural-symbol watermark message;

the configured device processor computing a watermark key that is dependent on an attribute associated with the host signal, or with an object used to convey the host signal, said attribute serving to associate the host signal or object with a proprietor; and

embedding the watermark message in the host signal such that the watermark signal is substantially imperceptible in the host signal;

wherein said watermark key specifies how or where the watermark message is embedded in the host signal.

2. The method of claim 1 wherein said attribute comprises a name of an individual.

3. The method of claim 2 that includes converting the name of an individual with a predetermined function, and computing the watermark key based thereon.

4. The method of claim 2 that includes indexing a data store using information related to the name of the individual, to retrieve information associated therewith, and computing the watermark key based on said retrieved information.

5. The method of claim 1 wherein said watermark key specifies a temporal location of the watermark message in the host signal.

6. The method of claim 1 wherein said watermark key specifies a spatial location of the watermark message in the host signal.

7. The method of claim 1 wherein said watermark key specifies host signal transform coefficients that are altered to encode the watermark message.

8. The method of claim 1 wherein the symbols comprising the watermark message are not dependent on the host signal.

9. A computer readable medium on which is stored software for performing the method of claim 1.

10. The method of claim 1 wherein the watermark key specifies how the watermark message is embedded in the host signal.

11. The method of claim 1 wherein the watermark key specifies where the watermark message is embedded in the host signal.

12. An apparatus for encoding auxiliary data into a host signal, comprising:

an input for receiving a plural-symbol watermark message;

computing means for computing a watermark key that is dependent on an attribute associated with the host signal, or with an object used to convey the host signal, said attribute serving to associate the host signal or object with a proprietor; and

embedding means for embedding the watermark message in the host signal such that the watermark signal is substantially imperceptible in the host signal;

wherein said watermark key specifies how or where the watermark message is embedded in the host signal.

13. The apparatus of claim 12 wherein the watermark key specifies where the watermark message is embedded in the host signal.

14. The apparatus of claim 12 wherein the watermark key specifies how the watermark message is embedded in the host signal.

15. An apparatus for encoding auxiliary data into a host signal, comprising:

an input for receiving a plural-symbol watermark message; and

a processor configured to;

compute a watermark key that is dependent on an attribute associated with the host signal, or with an object used to convey the host signal, said attribute serving to associate the host signal or object with a proprietor; and

embed the watermark message in the host signal such that the watermark signal is substantially imperceptible in the host signal;

wherein said watermark key specifies how or where the watermark message is embedded in the host signal.

16. The apparatus of claim 15 wherein the watermark key specifies where the watermark message is embedded in the host signal.

17. The apparatus of claim 15 wherein the watermark key specifies how the watermark message is embedded in the host signal.

18. A computer readable medium comprising software instructions for causing a processing device configured thereby to perform acts that include:

compute a watermark key that is dependent on an attribute associated with a host signal, or with an object used to convey the host signal, said attribute serving to associate the host signal or object with a proprietor; and

embed a plural-symbol watermark message in the host signal such that the watermark signal is substantially imperceptible in the host signal;

wherein said watermark key specifies how or where the watermark message is embedded in the host signal.

19. The apparatus of claim 18 wherein the watermark key specifies where the watermark message is embedded in the host signal.

20. The apparatus of claim 18 wherein the watermark key specifies how the watermark message is embedded in the host signal.