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:
Jan. 31, 2012
Filed:
Apr. 29, 2006
Bin Yang, Beijing, CN;
Wenzhe Shi, Beijing, CN;
Wenfa Qi, Beijing, CN;
Shengyuan Cheng, Beijing, CN;
Lidong Wang, Beijing, CN;
Bin Yang, Beijing, CN;
Wenzhe Shi, Beijing, CN;
Wenfa Qi, Beijing, CN;
Shengyuan Cheng, Beijing, CN;
Lidong Wang, Beijing, CN;
Peking University Founder Group Co., Ltd., Beijing, CN;
Beijing Founder Electronics Co., Ltd., Beijing, CN;
Peking University, Beijing, CN;
Abstract
Disclosed are a method and apparatus for embedding or detecting watermarks in a text, which belong to the field of document protection. The method and apparatus overlay an additional layer of shade in a document for recording a large amount of information from watermarks. The shade comprises the dots arranged under certain rules. Shifts of the dots record each bit string within the watermark. According to the method and apparatus, a large amount of information can be embedded and the watermarks embedded in the shade are dispersed together with the document which can be digitized by a scanner for being detected.