A Gray Level Watermarking Algorithm Using Double Layer Hidden Approach

Shih-Chang HSIA  I-Chang JOU  Shing-Ming HWANG  

IEICE TRANSACTIONS on Fundamentals of Electronics, Communications and Computer Sciences   Vol.E85-A   No.2   pp.463-471
Publication Date: 2002/02/01
Online ISSN: 
Print ISSN: 0916-8508
Type of Manuscript: PAPER
Category: Information Security
watermark,  data hiding,  robustness,  data compression,  

Full Text: PDF(1.3MB)>>
Buy this Article

Watermarking techniques are widely used to protect the secret document. In some valuable literatures, most of them concentrate on the binary data watermarking by using comparisons of an original image and a watermarked image to extract the watermark. In this paper, an efficient watermarking algorithm is presented with two-layer hidden for gray-level image watermarking. In the first layer, the key information is found based on the codebook concept. Then the secret key is further hidden to the watermarked image adopting the encryption consisting of spatial distribution in the second layer. The simulations demonstrate that the watermarking information is perceptually invisible in the watermarked image. Moreover, the gray-level watermark can be extracted by referring key parameters rather than the original image, and the extracting quality is very good.