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:
Aug. 06, 2002
Filed:
Sep. 24, 1999
Applicant:
Inventors:
Dan S. Bloomberg, Palo Alto, CA (US);
Robert E. Weltman, Los Altos, CA (US);
Assignee:
Xerox Corporation, Stamford, CT (US);
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
G06K 1/906 ;
U.S. Cl.
CPC ...
G06K 1/906 ;
Abstract
A specific bit pattern (or set of bit patterns) that have particular frequency and length requirements is used to remove low-frequency, visually observable structure from rendered embedded digital data. In use, the pattern is replicated enough times to be able to XOR with the data before rendering as glyphs, or the like. On decoding (reading), the read data is XOR'd again to recover the original data.