The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Feb. 21, 2012
Filed:
Apr. 29, 2006
Wenfa Qi, Beijing, CN;
Jiquan Xie, Beijing, CN;
Bin Yang, Beijing, CN;
Xiaohong Ding, Beijing, CN;
Jiang Deng, Beijing, CN;
Wenfa Qi, Beijing, CN;
Jiquan Xie, Beijing, CN;
Bin Yang, Beijing, CN;
Xiaohong Ding, Beijing, CN;
Jiang Deng, Beijing, CN;
Peking University Founder Group Co., Ltd.;, Beijing, CN;
Beijing Founder Electronics Co., Ltd.;, Beijing, CN;
Peking University, Beijing, CN;
Abstract
This invention relates to a method for preventing a copy of document, belonging to a technical field of entire copy protection of document. In the prior art, for some important documents, specially the secret ones, the reproduction of this kind of document is usually prohibited by its owner because of the security. But the technique in the prior art can not solve the problem of preventing unauthorized reproduction. The method of the present invention is intended to embed a shading pattern under the original image of anti-copy document by an application program installed in the copy device, and decide whether the document can be copied legally or not. By the method of present invention, it is possible to detect the watermark information of the anti-copy document accurately and quickly, and prevent the reproduction of the anti-copy document thoroughly. Moreover, an additional memory space is no need.