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:
Nov. 11, 2008
Filed:
Apr. 04, 2006
James David Johnston, Morristown, NJ (US);
Shyh-shiaw Kuo, Basking Ridge, NJ (US);
Schuyler Reynier Quackenbush, Basking Ridge, NJ (US);
William Turin, East Brunswick, NJ (US);
James David Johnston, Morristown, NJ (US);
Shyh-Shiaw Kuo, Basking Ridge, NJ (US);
Schuyler Reynier Quackenbush, Basking Ridge, NJ (US);
William Turin, East Brunswick, NJ (US);
AT&T Intellectual Property II, L.P., New York, NY (US);
Abstract
A method of retrieving a watermark in a watermarked signal involves processing a signal having odd- and even-overlapped blocks and where the watermark is contained in the even blocks. For each k-th block, the method comprises subtracting the odd-numbered blocks from the k-th block of the watermarked signal to generate*(n), applying an FFT to*(n) to generate a phase(ƒ), calculating a phase of(ƒ) as(ƒ) and a phase of an original signal S(ƒ) as φ(ƒ), calculating the difference Ψ(ƒ) between(ƒ) and φ(ƒ); and retrieving the watermark embedded in Ψ(ƒ). A Viterbi search may be the algorithm used to retrieve the watermark.