A Novel Robust Color Image Digital Watermarking Algorithm Based on Discrete Cosine Transform

Digital watermarking technology is a very good method for protecting copyright. In this paper, in terms of requisition of imperceptibility and robustness of watermarking, the coefficient features of Discrete Cosine Transform (DCT) are introduced and a new image watermarking scheme based on Discrete Cosine Transform is proposed. Digital watermark is embedded in original image by subtle perturbations of Discrete Cosine Transform corresponding coefficients. Experimental results show that the proposed watermarking scheme is feasible and simple, the embedded watermarking images have little difference with the original images and the extracted watermark is accurate. Moreover, it is imperceptible and robust against various signals processing such as noise adding, cropping, rotating and sharp, etc.