DCT-domain Watermarking Scheme Based on Majority Voting Criterion

Abstract

A robust watermarking strategy for copyright protection is proposed as a way that embeds multiple copyright information in a selected set of DCT coefficients. During watermark extraction, we introduce the majority voting scheme that can render more reliable watermark detection compared to some conventional image watermarking approaches. The proposed method can directly extract the embedded watermark form the watermarked image without using the original image, so it is feasible to implement it in a real time system. To further adaptively accommodate the characteristics of different images, the proposed algorithm uses an adaptive watermark strength factor (S) to strike a good balance between robustness and perceptual invisibility. Furthermore, the proposed algorithm can solve the problem inherent in traditional watermark systems: the security will degrade due to the publication of watermark algorithm. Experimental results demonstrate that the watermark is robust to most of the signal processing operations and geometric distortions. It can be found that detection capability, imperceptibility, and robustness of the watermarking technique can be guaranteed.