Method for utilizing fragile watermark for enhanced security

• US 7,171,020 B2
• Filed: 11/26/2003
• Issued: 01/30/2007
• Est. Priority Date: 05/08/1995
• Status: Expired due to Term

• Current Assignee: Digimarc Corporation
• Original Assignee: Digimarc Corporation
• Inventors: Rhoads, Geoffrey B., Gustafson, Ammon E.
• Primary Examiner(s): Johns; Andrew W.
• Application Number:
  US10/723,731
• Publication Number:
  US 20040190751A1
• Time in Patent Office: 1,161 Days
• Field of Search: 382/100, 382/232, 380/201, 380/210, 380/287, 380/54, 713/176, 399/366
• US Class Current: 382/100
• CPC Class Codes: G06T 1/0071 using multiple or alternating watermarks
• CPC Class Codes: G06T 2201/0051 Embedding of the watermark in the spatial domain
• CPC Class Codes: G06T 2201/0052 Embedding of the watermark in the frequency domain
• CPC Class Codes: G06T 2201/0202 whereby the quality of watermarked images is measured; Measuring quality or performance of watermarking methods; Balancing between quality and robustness
• CPC Class Codes: G06T 2207/30144 Printing quality
• CPC Class Codes: G06T 7/0002 Inspection of images, e.g. flaw detection
• CPC Class Codes: G06T 7/0004 Industrial image inspection
• CPC Class Codes: G07C 9/253 visually
• 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 7/12 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: H04N 1/00002 Diagnosis, testing or measuring; Detecting, analysing or monitoring not otherwise provided for error detection, error correction or monitoring in digital computers or digital computer components G06F11/00
• 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 1/00092 relating to the original or to the reproducing medium, e.g. imperfections or dirt detecting properties of a sheet H04N1/00681
• 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 1/32304 Embedding different sets of additional information
• CPC Class Codes: H04N 1/32309 : in colour image data
• CPC Class Codes: H04N 1/32315 : Selecting a particular method from amongst a plurality of methods
• CPC Class Codes: H04N 1/32331 : Fragile embedding or watermarking
• 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

Abstract

A fragile watermark is embedded in a document. The fragile watermark provides enhance security. In one implementation, a method is provided for embedding information in an image so that the image will have different information when a scanning or printing process reproduces the image. The method includes embedding digital information in an image; printing the embedded digital information and the image to produce a original printed image; scanning the original printed image to obtain a digital image of the embedded information and the image; determining the signal strength of the original image; and comparing the signal strength of a printed image with the signal strength of the original printed image to determine whether or not the printed image is a copy of the original printed image.

Claims

1. A method for embedding information in an image so that the image will have different information when the image is reproduced by a scanning or printing process, the method comprising:

embedding digital information in an image;

printing the embedded digital information and the image to produce an original printed image;

scanning the original printed image to obtain a digital image of the embedded information and the image;

determining the signal strength of the original image; and

comparing the signal strength of a printed image with the signal strength of the original printed image to determine whether or not the printed image is a copy of the original printed image.

2. The method claimed in claim 1, wherein the image is a graphic.

3. The method claimed in claim 1, wherein a bit map file is created for the original printed image.

4. The method claimed in claim 1, wherein the comparing step further comprises:

measuring the signal strength of the original printed image to set a threshold value for the original printed image and copies of the original printed image.

5. The method claimed in claim 4, whereby if the signal strength of a printed image is greater than the threshold value the printed image is the original printed image.

6. The method claimed in claim 4, whereby if the signal strength of a printed image is less than the threshold value the printed image is not the original printed image.

7. A method to determine whether an image or video has been reproduced, the method comprising:

receiving an image or video, wherein the image or video includes information steganographically hidden therein;

detecting signal characteristics associated with the steganographically hidden information from the image or video;

determining whether detected signal characteristics correspond to predetermined signal characteristics in an expected manner,

wherein a reproduction is determined when the detected characteristics do not correspond to the predetermined characteristics in the expected manner.

8. The method of claim 7 wherein the information steganographic hidden in the image or video comprises two or more steganographic watermarks.

9. The method of claim 8 wherein the predetermined characteristics correspond to a signal relationship between the two or more steganographic watermarks.