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. 02, 2006
Filed:
Jul. 17, 2002
Masahiko Suzaki, Tokyo, JP;
Masahiko Suzaki, Tokyo, JP;
Oki Electric Industry Co., Ltd., Tokyo, JP;
Abstract
There are disclosed a watermark information embedment device capable of accurately embedding secret information, and a watermark information detection device. In the watermark information embedment device, there are prepared a plurality of different sorts of dot patterns in which the wave propagation direction and the wave length are changed depending on the dot arrangement. Each dot pattern of the same sort is given the same symbol, and the secret information is represented by combining these dot patterns. In the watermark information detection device, there are provided 2-dimensional wavelet filters having the same wave propagation direction and the wave length as the different sorts of dot patterns. There is computed convolution between an arbitrary region in the watermarked image and plural 2-dimensional wavelet filters, and it is judged that the dot pattern corresponding to a particular one of the 2-dimensional wavelet filters is embedded in the region where the computed convolution indicates a maximum value.