No abstract

Nowadays, there is an explosive growth in the digital multimedia creation, capturing, processing and distribution. Protecting the multimedia contents from copyright in fingerprint has become a major concern. Encryption and watermarking are two complementary techniques that are used for protecting the multimedia data. In this paper, a proposed hybrid encryption-watermarking algorithm for copyright protection is proposed. The watermarking phase of this proposed algorithm is based on, the discrete cosine transform (DCT), while the encryption phase is based on using four chaotic maps with different dimensions. The proposed watermarking scheme uses a new PN-codes embedding strategy of the watermark into the cover image. This strategy allows decreasing the embedding strength factor of the scheme to a value that maximizes imperceptibility performance while maintaining acceptable robustness of the watermarking scheme. On the other hand, the proposed chaos-based encryption algorithm used four chaotic maps of different dimensions and it has two diffusion stages rather than one to improve the algorithm efficiency. The proposed encryption algorithm is tested using different experiments. The experimental results demonstrate that the proposed encryption algorithm shows advantages of large key space, high resistance against differential attacks and high security analysis such as statistical analysis, and sensitivity analysis.