Combined DWT and DFT Based Watermarking Technique with Improved Robustness |
Author(s): |
Dinah C. Kurian , Akshaya College Of Engineering And Technology; P. Damodharan, Akshaya College Of Engineering And Technology |
Keywords: |
HVS, DWT, DFT |
Abstract |
To protects intellectual property rights, the amount of exchanged digital content calls are rapidly growing based on efficient and practical techniques. During the past two decades, watermarking techniques have been presented to embed and detect information within such contents, with different four key requirements at hand, that are – capacity, invisibility, robustness, and security. So far, researchers mainly focused on the first three. Earlier work used novel DFT watermarking scheme featuring perceptually optimal visibility versus robustness. Then the perceptual model of the human visual system (HVS) based on the contrast sensitivity function (CSF) and a local contrast pooling is used to determine the optimal strength of the visibility threshold. However the problem found in this work is that robust watermarking result is not obtained and improved HVS is not produced for determining optimal strength of visibility threshold. To deal with this problem, the present work proposes Combined DWT and DFT to improve the watermarking accuracy. In the proposed method, host image is first wavelet transformed by using DWT and then DFT is applied to some selected high-frequency sub-bands of transformed image. In addition improved Human visual model is used based on identifying the areas of true high contrast texture while protecting connected directional edges. This improved HVS is used to determine the optimal strength of the visibility threshold. Experimental result provides better result when compare with the existing one. |
Other Details |
Paper ID: IJSRDV3I1174 Published in: Volume : 3, Issue : 1 Publication Date: 01/04/2015 Page(s): 587-590 |
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