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.

Date of Patent:
Nov. 13, 2007

Filed:

Nov. 25, 1998
Applicants:

Koichi Kamijo, Yokohama, JP;

Shuichi Shimizu, Yokohma, JP;

Norishige Morimoto, Tokyo-to, JP;

Inventors:

Koichi Kamijo, Yokohama, JP;

Shuichi Shimizu, Yokohma, JP;

Norishige Morimoto, Tokyo-to, JP;

Attorney:
Primary Examiner:
Int. Cl.
CPC ...
H04N 7/12 (2006.01);
U.S. Cl.
CPC ...
Abstract

It is one object of the present invention to provide a method and system for embedding an electronic watermark directly in an MPEG stream. An intra-macroblock of an I-frame or of a P or B-frame is detected in an MPEG stream, and following the detection of an intra-macroblock of the I-frame or of the P or B-frame, data for one macroblock are extracted from the MPEG stream and buffered. An embedding pattern is embedded in the buffered macroblock without changing the length of VLC, and the resultant macroblock is returned to the MPEG stream. More specifically, a DC factor is extracted from the buffered macroblock, and a pseudorandom number is generated to produce an embedding pattern. Then, whether the bit length of the DC factor will not be changed by embedding the obtained embedded pattern is determined. When the bit length of the DC factor not be changed, the embedding pattern is embedded in the buffered macroblock. When the bit length will be changed, whether ½ of the embedding pattern can be embedded is determined. If possible, ½ of the embedded pattern is embedded in the macroblock.


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