Identification/authentication system using robust, distributed coding

• US 5,745,604 A
• Filed: 03/15/1996
• Issued: 04/28/1998
• Est. Priority Date: 11/18/1993
• Status: Expired due to Term

• Current Assignee: Digimarc Corporation
• Original Assignee: Digimarc Corporation
• Inventors: Rhoads, Geoffrey B.
• Primary Examiner(s): Boudreau, Leo
• Assistant Examiner(s): Mehta, Bhavesh
• Application Number:
  US08/614,521
• Time in Patent Office: 774 Days
• Field of Search: 380/3, 380/6, 380/19, 380/23, 380/26, 380/49, 380/54, 380/55, 380/4, 380/10, 380/51, 380/5, 379/95, 341/67, 283/73, 283/113, 283/83, 283/82, 116/18, 395/375, 382/232, 382/100, 382/276, 382/112, 382/115, 382/135, 382/181, 381/124, 381/29, 381/181, 348/460
• US Class Current: 382/232
• 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 1/005 Robust watermarking, e.g. average attack or collusion attack resistant
• CPC Class Codes: G06T 1/0057 Compression invariant watermarking
• CPC Class Codes: G06T 2201/0052 Embedding of the watermark in the frequency domain
• CPC Class Codes: G06T 2201/0065 Extraction of an embedded watermark; Reliable detection
• 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: G07C 9/253 visually
• CPC Class Codes: G07D 7/0032 using holograms
• CPC Class Codes: G07D 7/004 using digital security elements, e.g. information coded on a magnetic thread or strip
• CPC Class Codes: G07F 17/16 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 20/00884 : 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: 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 1/00838 : Preventing unauthorised reproduction
• CPC Class Codes: H04N 1/00846 : based on detection of a dedicated indication, e.g. marks or the like
• 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 1/32149 : Methods relating to embedding, encoding, decoding, detection or retrieval operations
• 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 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 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 2201/3226 : 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 2201/328 : Processing of the additional information
• CPC Class Codes: H04N 5/913 : for scrambling ; for copy protection

Abstract

An identification code signal is impressed on a carrier to be identified (such as an electronic data signal or a physical medium) in a manner that permits the identification signal later to be statistically discerned and the carrier thereby identified. The method and apparatus are characterized by robustness despite degradation of the encoded carrier, and by holographic permeation of the identification signal throughout the carrier.

Claims

1. In a method of image processing that includes processing an input image to steganographically encode a multi-bit message code therein, thereby yielding an encoded output image, and thereafter processing suspect data corresponding to said encoded output image to decode the message code therefrom, an improvement including:

encoding the message code redundantly through the image data, wherein the message code can be detected from first and second non-overlapping rectangular excerpts thereof; and

decoding the message code from said suspect data without reference to said input image, said decoding including performing a domain transformation on a first set of data related to said suspect data, said domain transformation producing transformed data in a spatial frequency domain, and analyzing said transformed data.

2. The method of claim 1 in which said steganographic encoding includes processing the input image in accordance with key data in addition to said message code, each element of the input image having an element of said key data corresponding thereto.

3. The method of claim 2 in which the key data causes the message code to be represented differently at different locations in the encoded output image.

4. The method of claim 1 in which said first set of data is distinct from said suspect data, said first set of data being a set of difference data obtained by subtracting a second second data from said suspect data.

5. The method of claim 1 in which said domain transformation is a Fourier transformation.

6. The method of claim 1 in which said input image is obtained by a camera, and said processing includes exposing an emulsion film with said input image, said emulsion film having been pretreated to embed the multi-bit message code redundantly therethrough.

7. A method of video processing, the video including a plurality of frames, comprising performing the method of claim 1 on a plurality of said frames.

8. In an image processing method that includes steganographically encoding an input two-dimensional image to embed a multi-bit message code therein, the image comprising a plurality of rows of picture data, the method including processing said input image in accordance with said multi-bit message code to produce an output image having the message code encoded therein, an improvement including:

encoding the message code throughout the output image so that the message code can be recovered from first and second non-overlapping rectangular excerpts of the output image; and

representing a given bit of the encoded message code differently, both in absolute and percentage terms, in said first and second excerpts to reduce image degradation and increase message security, said encoding including changing a plurality of said picture data in accordance with said multi-bit message code, and also in accordance with local scaling data to control the amplitude of the multi-bit message code at different locations in the image, said local scaling data being computed from said picture data using a non-linear function.

9. The method of claim 8 which includes deriving the local scaling data from picture data related thereto by use of a non-linear function, wherein doubling the value of picture data does not double the local scaling data corresponding thereto.

10. The method of claim 8 in which the local scaling data is also a function of first and second non-unity parameters.

11. A method of video processing, the video including a plurality of frames, comprising performing the method of claim 8 on a plurality of said frames.

12. In an image processing method that includes steganographically encoding an input two-dimensional image to embed a multi-bit message code therein, the image comprising a plurality of rows of picture data, the method including processing said input image in accordance with said multi-bit message code to produce an output image having the message code encoded therein, an improvement including:

encoding the message code throughout the output image so that the message code can be recovered from first and second non-overlapping rectangular excerpts of the output image;

said encoding including determining a scaling factor for each of a plurality of regions of the input image, each scaling factor being a non-linear function of picture data related thereto, wherein doubling the value of picture data does not double the scaling factor corresponding thereto, the encoding further including processing the input image in accordance with said scaling factors in addition to said noise data and said message code to produce an output image.

13. The method of claim 12 in which the scaling factors are each a function of first and second non-unity parameters.

14. A method of video processing, the video including a plurality of frames, comprising performing the method of claim 12 on a plurality of said frames.