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:
May. 05, 2009
Filed:
Sep. 12, 2006
James David Johnston, Morristown, NJ (US);
Shyh-shiaw Kuo, Basking Ridge, NJ (US);
Schuyler Reynier Quackenbush, Westfield, NJ (US);
William Turin, East Brunswick, NJ (US);
James David Johnston, Morristown, NJ (US);
Shyh-Shiaw Kuo, Basking Ridge, NJ (US);
Schuyler Reynier Quackenbush, Westfield, NJ (US);
William Turin, East Brunswick, NJ (US);
AT&T Intellectual Property II, L.P., New York, NY (US);
Abstract
A system and method of retrieving a watermark in a watermarked signal are disclosed. The watermarked signal comprises odd and even overlapped blocks where the watermark is contained in the even blocks. The method comprises, for each k-th even block, subtracting the two adjacent odd numbered blocks from the k-th even block of the watermarked signal to retrieve*(n), transforming*(n) into the frequency domain to generate(f), calculating a phase of(f) as(f) and a phase of S(f) as φ(f), calculating the difference Ψ(f) between(f) and φ(f), unwrapping Ψ(f) to obtain the phase modulation {tilde over (φ)}(f), and using a Viterbi search to retrieve the watermark embedded in {tilde over (Φ)}(f).