Title:
可視的認証パターンを検出、解析および使用するための改良された技法
Document Type and Number:
Japanese Patent JP2007523526
Kind Code:
A
Abstract:
Improved techniques for making copy detection patterns and using them to detect copying relationships between digital representations. The techniques include techniques for including a message in a copy detection pattern without altering the copy detection patterns entropy and reading the message, techniques for using a copy detection pattern on an analog form to determine whether the analog form is an original analog form without reference to a digital representation of the original of the analog form's copy detection pattern, techniques for increasing the sensitivity of copy detection using copy detection patterns by modifying one of two copy detection patterns that are being compared to take into account alterations resulting from the copying process, techniques for distributing a copy detection pattern across a document, and techniques for using the entropy of a copy detection pattern to locate the copy detection pattern. Also disclosed are applications of copy detection patterns with copying that involves transformations between the digital and analog forms and with digital-to-digital copying.
Inventors:
Picard, justin
Jiao, Jiang
Jiao, Jiang
Application Number:
JP2006549365A
Publication Date:
August 16, 2007
Filing Date:
January 06, 2005
Export Citation:
Assignee:
Thomson Licensing
International Classes:
H04N1/387; B41J21/00; G06T1/00; H04N1/32; H04N1/40
Foreign References:
| US20030156733A1 | 2003-08-21 |
Attorney, Agent or Firm:
Tadahiko Ito
Shinsuke Onuki
Tadashige Ito
Shinsuke Onuki
Tadashige Ito