A DC-based approach to robust watermarking with hamming-code

In the past decade, watermarking technology had been recognized as a significant security technique to protect valuable digital contents. However, the robustness against possible attacks, including codec, is concerned by many researchers. In this paper, a DC-based approach to robust watermarking is proposed. Although classical watermarking schemes had been widely developed in frequency-domain hide information, hidden information usually is corrupted and damaged by ordinary codec operations. The lack of robustness against possible codec attack is an important issue of advanced watermarking technique. In this study, we find the polarity of DC components in each image block is robust to the DCT/IDCT operations. Thus, a new watermarking scheme based DC-component is developed. In this proposed scheme, information bits are encoded and hidden in the DC-components of each image block. The experimental results indicate that (1) hidden information can be recovered from compression/decompression attacks and (2) the information-hiding process is low computation-complexity. Besides, the relationship between block size and the amount of hidden information is also investigated to illustrate the deployment strategy in real applications.