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:
Sep. 02, 1997
Filed:
Mar. 12, 1996
Applicant:
Inventor:
Frank Thomson Leighton, Newtonville, MA (US);
Assignee:
Other;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
G09C / ; H04L / ;
U.S. Cl.
CPC ...
380 54 ; 380-3 ; 380-4 ; 380 23 ; 380 55 ; 283 73 ; 283113 ; 283 17 ;
Abstract
A watermarking procedure wherein each of a set of copies of the work has a slightly-modified form of a 'baseline' watermark that is placed within a critical region of the data. The slight variations in the watermarks, however, are not perceptually visible and do not interfere with the work. If multiple persons collude to attempt to create an 'illicit' copy of the work (i.e., a copy without a watermark), however, at least one of the modified watermarks is present in the copy, thereby identifying both the illicit copy and the copier.
Published as: