Encoding hidden data

• US 7,136,503 B2
• Filed: 03/07/2005
• Issued: 11/14/2006
• Est. Priority Date: 07/31/1992
• Status: Expired due to Fees

• Current Assignee: Digimarc Corporation
• Original Assignee: Digimarc Corporation
• Inventors: Nitzberg, Mark, Powell, Robert D.
• Primary Examiner(s): Johns, Andrew W.
• Application Number:
  US11/074,520
• Publication Number:
  US 20050147275A1
• Time in Patent Office: 617 Days
• Field of Search: 382/100, 382/232, 380/210, 380/252, 380/287, 380/54, 713/176, 370/527, 370/529
• US Class Current: 382/100
• 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: G06T 1/0028 Adaptive watermarking, e.g. Human Visual System [HVS]-based watermarking
• CPC Class Codes: G06T 1/0064 Geometric transfor invariant watermarking, e.g. affine transform invariant
• CPC Class Codes: G06T 2201/0051 Embedding of the watermark in the spatial domain
• CPC Class Codes: G06T 2201/0081 whereby both original and watermarked images are required at decoder, e.g. destination-based, non-blind, non-oblivious
• CPC Class Codes: G07D 7/0047 using checkcodes, e.g. coded numbers derived from serial number and denomination
• CPC Class Codes: G07D 7/0056 involving markings of altered colours
• CPC Class Codes: G07D 7/12 Visible light, infrared or ultraviolet radiation
• CPC Class Codes: G07D 7/2008 using pre-processing, e.g. de-blurring, averaging, normalisation or rotation
• CPC Class Codes: G07D 7/2033 Matching unique patterns, i.e. patterns that are unique to each individual paper
• 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 7/12 Card verification
• 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 1/32229 with selective or adaptive application of the additional information, e.g. in selected regions of the image H04N1/32213 takes precedence
• CPC Class Codes: H04N 1/32245 Random or pseudorandom selection of pixels
• 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 1/3232 Robust embedding or watermarking
• CPC Class Codes: H04N 2201/3233 of authentication information, e.g. digital signature, watermark
• 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 2201/327 : which are undetectable to the naked eye, e.g. embedded codes

Abstract

A digital image is processed to hide information, by generally inconspicuous adjustments thereof. These adjustments can define a pattern that extends across some or all of the image. Desirably, the pattern is adapted to the particular image being encoded, so as to better conceal the encoding.

Claims

1. A method of processing entertainment content data to encode hidden information therein, comprising:

by reference to characteristics of the entertainment content data, establishing an initial pattern;

generating a second pattern by processing said initial pattern in accordance with symbols of a message; and

combining the second pattern with said entertainment content data to yield encoded content data.

2. The method of claim 1 that further includes processing the second pattern to adapt its local strength to local characteristics of the entertainment content.

3. The method of claim 1 in which said entertainment content comprises image data.

4. The method of claim 3 in which said entertainment content comprises motion picture data.

5. The method of claim 1 in which the message comprises an N-bit code.

6. The method of claim 5 in which N is at least two.

7. The method of claim 1 in which the entertainment content comprises image data, and said combining occurs in a pixel domain, rather than in a transform domain.

8. The method of claim 1 in which the entertainment content includes image data, and the method further includes:

rendering the processed image data on a surface;

sensing said image from the surface; and

recovering the hidden information notwithstanding losses associated with said rendering/sensing of said image.

9. A computer storage medium having stored thereon instructions for causing a programmable device to perform the method of claim 1.

10. The method of claim 1 that includes storing the encoded content data on a computer-readable storage medium.

11. A method of processing image data to encode hidden information, comprising:

analyzing the image data to identify potential locations for encoding data;

selecting a subset of the identified locations; and

changing the image data at said selected locations.

12. The method of claim 11 wherein:

the image data comprises pixels, each having a value;

said analyzing proceeds in the pixel domain; and

said changing comprises increasing pixel values at some of said selected locations, and decreasing pixel values at others of said selected locations.

13. The method of claim 11 that further includes:

rendering the processed image data on a surface;

sensing said image from the surface; and

recovering the hidden information notwithstanding losses associated with said rendering/sensing of said image.

14. A method of processing image data to encode hidden information, comprising:

analyzing the image data to identify components thereof to which local functions can be applied without noticeable visual impairment of the image; and

controlling the sign of each local function in accordance with the information to be hidden in the image.

15. The method of claim 14 that further includes applying said sign-controlled local functions to the image data.

16. The method of claim 14 wherein said analysis of the image data occurs in the pixel domain.

17. The method of claim 16 wherein each local function comprises a percentage change in pixel value to a central pixel, and a lesser percentage change in pixel value to neighboring pixels.

18. The method of claim 14 that further includes:

rendering said processed image on a surface;

sensing said image from the surface; and

recovering the hidden information notwithstanding losses associated with said rendering/sensing of said image.

19. A method of processing an image to encode hidden information, the method including:

analyzing image data to generate first information related thereto; and

by reference to said first information, selecting components of said image data that can be altered to convey information inconspicuously.

20. The method of claim 19 that includes altering the selected components of said image data.