A robust wavelet-based watermarking scheme for copyright protection of digital images

The recent advancement in the digital multimedia technologies has presented many facilities in the transmission, reproduction and manipulation of digital images. Nevertheless, the advancement has also brought about problems such as copyright protection for content providers. Digital watermarking is one of the proposed solutions for copyright protection of digital images. A wide variety of watermarking techniques have been proposed by researchers for the copyright protection of digital images. This paper presents a novel robust invisible watermarking scheme for embedding and extracting a digital watermark in an image to protect its copyrights. The invisible insertion of the watermark image into the original image is performed in wavelet domain using Haar wavelet transform. A mask matrix is generated using the original image with the aid of MD5 algorithm and random matrix generation. The generated mask matrix is utilized in both embedding and extraction processes. The watermark is extracted by computing the relationship degrees between the mask matrix and the watermark embedded wavelet coefficients. The results of the experimentation using attacks demonstrate the robustness and efficacy of the proposed watermarking scheme. Ownership proof could be established under various hostile attacks.