A Robust DWT-DCT Watermarking Technique with Double Chaotic Maps

In this paper a proficient digital watermarking strategy is proposed for copyright insurance. The proposed watermarking algorithm embed a binary logo watermark into main image additionally the security of logo is kept up by utilizing the chaotic maps after which it is transformed to DCT domain and then inserted into main image by detecting the suitable sub-band component in the wavelet domain. The horizontal and vertical wavelet components of level 2, 3 or higher depending upon the size of watermark are used to implant the digital watermark. The approach can successfully embed a greatly invisible watermark due to the perfect selection of embedding components in wavelet domain which perfectly exploits the limitations of human visual perception system. The watermark is recovered by (1) contrasting the relationships between the wavelet coefficients of watermarked image (2) the public key codes generated during embedding process and (3) the private key generated data. The experimental result shows the robustness of the proposed watermarking technique against different of image modification operations for example, compression, noise, and geometric operations.