Table of Contents
Advances in Computer Engineering
Volume 2014 (2014), Article ID 580697, 8 pages
http://dx.doi.org/10.1155/2014/580697
Research Article

An Improvement Technique Based on Structural Similarity Thresholding for Digital Watermarking

1Department of Electrical and Computer Engineering, University of British Columbia, Vancouver, BC, Canada V6T 2G9
2Department of Electrical and Computer Engineering, Ferdowsi University of Mashhad, Mashhad, Iran
3Department of Electrical and Computer Engineering, Yazd University, Yazd, Iran
4Department of Electrical and Computer Engineering, University of Tehran, Tehran, Iran

Received 29 July 2014; Revised 3 December 2014; Accepted 4 December 2014; Published 18 December 2014

Academic Editor: Ying-Tung Hsiao

Copyright © 2014 Amin Banitalebi-Dehkordi et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract

Digital watermarking is extensively used in ownership authentication and copyright protection. In this paper, we propose an efficient thresholding scheme to improve the watermark embedding procedure in an image. For the proposed algorithm, watermark casting is performed separately in each block of an image, and embedding in each block continues until a certain structural similarity threshold is reached. Numerical evaluations demonstrate that our scheme improves the imperceptibility of the watermark when the capacity remains fixed, and at the same time, robustness against attacks is assured. The proposed method is applicable to most image watermarking algorithms. We verify this issue on watermarking schemes in discrete cosine transform (DCT), wavelet, and spatial domain.