Methods for marking images

• US 7,308,110 B2
• Filed: 02/26/2003
• Issued: 12/11/2007
• Est. Priority Date: 11/18/1993
• Status: Expired due to Fees

• Current Assignee: Digimarc Corporation
• Original Assignee: Digimarc Corporation
• Inventors: Rhoads, Geoffrey B.
• Primary Examiner(s): Couso, Jose L.
• Application Number:
  US10/377,170
• Publication Number:
  US 20030228031A1
• Time in Patent Office: 1,749 Days
• Field of Search: 382/100, 380200-203, 380/210, 380/216, 380/231, 380/252, 380/287, 380/51, 380/54, 348/473, 348/474, 348/460, 370/527, 370/528, 370/529, 381/73.1, 235/494, 386/94, 704/270, 705/44, 713/176, 713/200, 713/201, 358/3.28
• US Class Current: 382/100
• CPC Class Codes: B42D 25/00 Information-bearing cards or sheet-like structures characterised by identification or security features; Manufacture thereof printing processes to produce identification or security features B41M3/14
• CPC Class Codes: G06F 16/955 using information identifiers, e.g. uniform resource locators [URL]
• CPC Class Codes: G06K 19/06037 multi-dimensional coding
• CPC Class Codes: G06K 19/06046 Constructional details
• CPC Class Codes: G06K 19/14 the marking being sensed by radiation
• CPC Class Codes: G06K 19/18 Constructional details
• CPC Class Codes: G06K 2019/06253 for a specific application
• CPC Class Codes: G06K 7/1417 2D bar codes
• CPC Class Codes: G06K 7/1447 extracting optical codes from image or text carrying said optical code
• CPC Class Codes: G06Q 20/1235 with control of digital rights management [DRM]
• CPC Class Codes: G06Q 20/341 Active cards, i.e. cards including their own processing means, e.g. including an IC or chip
• CPC Class Codes: G06Q 20/40145 Biometric identity checks
• CPC Class Codes: G06T 1/0021 Image watermarking
• CPC Class Codes: G06T 1/005 Robust watermarking, e.g. average attack or collusion attack resistant
• CPC Class Codes: G06T 1/0064 Geometric transfor invariant watermarking, e.g. affine transform invariant
• CPC Class Codes: G06T 2201/0052 Embedding of the watermark in the frequency domain
• CPC Class Codes: G06V 30/40 Document-oriented image-based pattern recognition
• CPC Class Codes: G07C 9/253 visually
• CPC Class Codes: G07D 7/0032 using holograms
• CPC Class Codes: G07D 7/0034 using watermarks
• CPC Class Codes: G07D 7/004 : using digital security elements, e.g. information coded on a magnetic thread or strip
• CPC Class Codes: G07F 17/0014 : for vending, access and use of specific services not covered anywhere else in G07F17/00 meter-controlled dispensing of liquid, gas or electricity G07F15/00
• CPC Class Codes: G07F 17/16 : for devices exhibiting advertisements, announcements, pictures or the like
• CPC Class Codes: G07F 17/26 : for printing, stamping, franking, typing or teleprinting apparatus ticket printing or the like apparatus G07F17/42
• CPC Class Codes: G07F 7/08 : by coded identity card or credit card or other personal identification means without personal verification means G07F7/02
• CPC Class Codes: G07F 7/086 : by passive credit-cards adapted therefor, e.g. constructive particularities to avoid counterfeiting, e.g. by inclusion of a physical or chemical security-layer for security documents G07D7/00; for the reading of record-carriers in general G06K7/00; for the design of coded credit-cards G06K19/10
• CPC Class Codes: G07F 7/1008 : Active credit-cards provided with means to personalise their use, e.g. with PIN-introduction/comparison system
• CPC Class Codes: G07F 7/1016 : Devices or methods for securing the PIN and other transaction-data, e.g. by encryption arrangements for secret communication, see H04L9/00
• CPC Class Codes: G07F 7/12 : Card verification
• CPC Class Codes: G10L 19/018 : Audio watermarking, i.e. embedding inaudible data in the audio signal
• 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 20/00094 : involving measures which result in a restriction to authorised record carriers
• CPC Class Codes: G11B 20/00115 : wherein the record carrier stores a unique medium identifier
• CPC Class Codes: G11B 20/00166 : involving measures which result in a restriction to authorised contents recorded on or reproduced from a record carrier, e.g. music or software
• CPC Class Codes: G11B 20/00181 : using a content identifier, e.g. an international standard recording code [ISRC] or a digital object identifier [DOI]
• CPC Class Codes: G11B 20/0021 : involving encryption or decryption of contents recorded on or reproduced from a record carrier
• CPC Class Codes: G11B 20/00231 : wherein the key is obtained from a local external medium, e.g. a card
• CPC Class Codes: G11B 20/0071 : involving a purchase action
• 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 20/00891 : embedded in audio data
• CPC Class Codes: H04B 1/665 : using psychoacoustic properties of the ear, e.g. masking effect
• CPC Class Codes: H04L 2463/103 : applying security measure for protecting copy right protecting software against unauthorised usage in a vending or licensing environment, e.g. protection the software providers copyright G06F21/10; data processing systems or methods, specially adapted for payment schemes, architectures or protocols G06Q20/00; secrecy systems or subscription systems H04N7/16
• CPC Class Codes: H04N 1/00005 : relating to image data
• CPC Class Codes: H04N 1/00037 : Detecting, i.e. determining the occurrence of a predetermined state H04N1/00031 takes precedence
• CPC Class Codes: H04N 1/00079 : remotely
• CPC Class Codes: H04N 1/32122 : in a separate device, e.g. in a memory or on a display separate from image data
• 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 1/3216 : using Fourier transforms
• CPC Class Codes: H04N 1/32203 : Spatial or amplitude domain methods H04N1/32309 takes precedence
• 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 1/32251 : in multilevel data, e.g. greyscale or continuous tone data
• 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 1/32352 : Controlling detectability or arrangements to facilitate detection or retrieval of the embedded information, e.g. using markers for decoding, detection or retrieval operations H04N1/32149 and subgroups take precedence
• CPC Class Codes: H04N 2005/91321 : the copy protection signal being a copy protection control signal, e.g. a record inhibit signal
• 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 21/8358 : 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 2201/3205 : of identification information, e.g. name or ID code H04N2201/3209 takes precedence
• CPC Class Codes: H04N 2201/3207 : of an address
• CPC Class Codes: H04N 2201/3225 : of data relating to an image, a page or a document
• CPC Class Codes: H04N 2201/3226 : of identification information or the like, e.g. ID code, index, title, part of an image, reduced-size image
• 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 2201/3271 : Printing or stamping
• CPC Class Codes: H04N 2201/3274 : Storage or retrieval of prestored additional information
• CPC Class Codes: H04N 2201/328 : Processing of the additional information
• CPC Class Codes: H04N 5/913 : for scrambling ; for copy protection
• CPC Class Codes: H04W 24/00 : Supervisory, monitoring or testing arrangements

Abstract

An image is marked by making slight changes to pixel values. These changes are essentially imperceptible on human scrutiny, but detectable by computer analysis. Such markings have applications in identifying ownership of images (including video), and also in device control (e.g., triggering a “do not copy” response in suitably configured hardware and software systems).

Claims

1. A method for imparting a watermark onto a digital image, said method comprising:

providing a digital image said image being represented by an image array having a plurality of pixels, said pixels being obtained from digitizing a color image,

said watermark being formed using an array having a plurality of distinct watermarking elements, each of said distinct watermarking elements having an array position and having one-to-one positional correspondence with said image pixels,

and adjusting said brightness data associated with said pixels by a predetermined brightness, wherein said brightness is a corresponding distinct watermarking element, and said watermark has an invisibility classification.

2. A method as recited in claim 1, wherein said predetermined brightness has a relationship with a number taken from a random number sequence.

3. A method as recited in claim 2, wherein said relationship is a scaling to provide a desired strength.

4. A method as recited in claim 3, wherein said strength lies in the domain greater than or equal to zero and less than or equal to 0.5.

5. A computer program product comprising a computer usable medium having computer readable program code means embodied therein for causing a watermark to be imparted into an image, the computer readable program code means in said computer program product comprising computer readable program code means for causing a computer to effect the steps of claim 1.

6. An apparatus to impart a watermark onto a digital image, said apparatus comprising mechanisms for implementing the method of claim 1.

7. A method for imparting a watermark onto a digital image comprising the steps of:

providing said digital image comprised of a plurality of pixels, wherein each of said pixels includes brightness data that represents a brightness of the digital image, the digital image obtained from digitizing a color image;

and altering said brightness data associated with a plurality of said pixels without changing color;

wherein said image has I rows and J columns, and has a pixel in row i and column j having at least one brightness, Y(i, j),

and the step of altering includes;

adding to or subtracting from the brightness Y(i, j) a different small random value ∈

(i, j), wherein 1 is less than or equal to i is less than or equal to I and 1 is less than or equal to j is less than or equal to J are the row and column indices of a pixel location in the image.

8. A method as recited in claim 7, including scaling ∈

(i, j) as a function of an original brightness of the pixel.

9. A computer program product comprising a computer usable medium having computer readable program code means embodied therein for causing a watermark to be imparted into an image, the computer readable program code means in said computer program product comprising computer readable program code means for causing a computer to effect the steps of claim 7.

10. An apparatus for imparting a watermark onto a digital image comprising mechanisms for implementing the method of claim 7.

11. A method for imparting a watermark onto a digital image comprising the steps of:

providing said digital image comprised of a plurality of pixels, wherein each of said pixels includes brightness data that represents a brightness of the digital image, with said digital image having I rows and J columns, and a pixel in row i and column j having a brightness Y(i, j); and

for a plurality i and at least one j adding to or subtracting from the brightness Y(i, j) a random value ∈

(i, j), wherein 1 is less than or equal to i is less than or equal to I and 1 is less than or equal to j is less than equal to J are the row and column indices of a pixel location in the image.

12. A method as recited in claim 11, wherein ∈

(i, j) is in the domain 0 to 1 multiplied by Y(i, j).

13. A computer program product comprising a computer usable medium having computer readable program code means embodied therein for causing a watermark to be imparted into an image, the computer readable program code means in said computer program product comprising computer readable program code means for causing a computer to effect the steps of claim 11.

14. An apparatus for imparting a watermark onto a digitized image comprising mechanisms for implementing the method of claim 11.

15. A method for generating a watermarked image, the method comprising:

imparting a watermark onto a digital image having a plurality of original pixels, each of said pixels having at least one original pixel brightness value;

providing said digital watermarking signal comprising a plurality of watermarking elements, each element having a watermark brightness and having one-to-one positional correspondence with said original pixels; and

producing a watermarked image by adjusting said original brightness of each of said original pixels by said brightness of a corresponding one of said watermark elements.

16. A computer program product comprising a computer usable medium having computer readable program code means embodied therein for causing generation of a watermarked image, the computer readable program code means in said computer program product comprising computer readable program code means for causing a computer to effect the steps of claim 15.

17. An apparatus for generating a watermarked image comprising mechanisms for implementing the method of claim 15.

18. A method for imparting a watermark onto a digital image comprising the steps of:

providing said digital image comprised of a plurality of image pixels with said digitized image having I rows and J columns, and a pixel in row i and column j having at least one component, Y(i, j); and

adding to or subtracting from said brightness data associated with at least one of said pixels a predetermined brightness adding factor in the range of 0 to Y(i, j), or brightness subtracting factor in the range of 0 to Y(i, j), wherein said brightness adding or subtracting factor has a relationship with a number taken from a random number sequence, said relationship is a scaling to provide a desired strength, and said strength is less than or equal to 50 percent.

19. An article of manufacture comprising a computer usable medium having computer readable program code means embodied therein for causing a watermark to be imparted onto a digital image, the computer readable program code means in said article of manufacture comprising computer readable program code means for causing a computer to effect the steps of claim 18.

20. A method for imparting a watermark onto a digital image comprising the steps of:

providing said digital image comprised of a plurality of image pixels with said image having I rows and J columns, and a pixel in row i and column j having at least one component, Y(i, j); and

adding to or subtracting from brightness data associated with at least one of said pixels by a predetermined brightness adding or subtracting factor in the range of 0 to Y(i, j), wherein said brightness adding or subtracting factor has a relationship with a number taken from a random number sequence, said relationship is a scaling to provide a desired strength, said sequence is formed from a plurality of robust watermarking parameters, and said parameters comprise a cryptographic key, and an initial value of said random number generator.

21. An article of manufacture comprising a computer usable medium having computer readable program code means embodied therein for causing a watermark to be imparted onto a digital image, the computer readable program code means in said article of manufacture comprising computer readable program code means for causing a computer to effect the steps of claim 20.

22. An apparatus for imparting a watermark onto a digital image comprising mechanisms for implementing the method of claim 20.

23. A method for detecting a watermarking plane comprising the steps of:

providing an image having a plurality of image pixels, u(i, j), with said image having I rows and J columns, and a pixel in row i and column j having at least one component, marked by a watermarking signal;

said watermarking signal having a plurality of watermarking elements, w(i, j), with said watermarking signal having I rows and J columns, and an element in row i and column j having a brightness;

aligning said watermarking plane with said image;

identifying a subset of said image elements; and

for each pixel, u(i, j), of said subset of image pixels, employing a detection scheme in determining a probability of watermark detection based on a property of random brightness adding or subtracting factors.