Method of processing image information and method of preventing forgery of certificates or the like

• US 6,724,921 B2
• Filed: 06/11/2002
• Issued: 04/20/2004
• Est. Priority Date: 12/03/1997
• Status: Expired due to Term

• Current Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation)
• Original Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation)
• Inventors: Yamaguchi, Takashi
• Primary Examiner(s): Patel, Jayanti K.
• Application Number:
  US10/166,165
• Publication Number:
  US 20020181025A1
• Time in Patent Office: 679 Days
• Field of Search: 382/100, 382/112, 382/115, 382/118, 382/162, 382/216, 382/282, 382/283, 382/306, 382/232, 235/384, 380/252, 713/176, 713/179, 713/186
• US Class Current: 382/118
• CPC Class Codes: B41J 2/2114 Ejecting specialized liquids, e.g. transparent or processing liquids B41J2/211 takes precedence
• CPC Class Codes: G06T 1/0021 Image watermarking
• CPC Class Codes: G06T 1/0028 Adaptive watermarking, e.g. Human Visual System [HVS]-based watermarking
• CPC Class Codes: G06T 2201/0051 Embedding of the watermark in the spatial domain
• 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 1/32304 Embedding different sets of additional information
• CPC Class Codes: H04N 1/32309 in colour image data
• CPC Class Codes: H04N 2201/3233 of authentication information, e.g. digital signature, watermark
• CPC Class Codes: H04N 2201/3261 of multimedia information, e.g. a sound signal
• 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 2201/3278 Transmission

Abstract

Additional information, composed of characters, images, voice, etc., is converted into two-dimensional codes and then converted into a visible additional image to be embedded. The additional image is embedded in a full-color main image in a state of invisibility to produce a composite image. The composite image is recorded on a non-electronic medium such as paper or on an electronic medium, such as a memory on a personal computer, over the Internet. The embedded additional image is extracted from the composite image recorded on the recording medium and the additional information is reproduced.

Claims

1. A method of preventing the forgery of identity cards comprising:

preparing an image of the face of a person for identification and a composite image in which security information for assuring the image of the face of the person is embedded in a state of invisibility; and

recording the image of the face of the person and the composite image in different positions on an identity card,

wherein the composite image is produced by

converting a main image comprising an image of the person'"'"'s face into achromatic image information,

modulating an additional image comprising characters or images using predetermined pattern image information to produce a pattern-modulated image information,

adding predetermined color difference amounts to the resulting pattern-modulated image information, and

superimposing the pattern-modulated image information having the color difference amounts added on the main image converted into the achromatic image information.