This paper presents a novel dual watermarking mechanism for digital media that embeds a recognizable pattern into the spatial domain and an invisible logo into the frequency domain. Undoubtedly, visible watermarking is important for protecting online resources from unauthorized reproduction. Due to the visibility of embedded patterns, however, watermarked digital media are vulnerable to the inpainting attack and common signal processing operations. Utilizing hybrid strategies, simulation results show that the novel method can resist these attacks. In particular, the new mechanism allows legal subscribers to restore an unmarked image, whereas other dual watermarking schemes do not. This feature makes it suitable for protecting artistic and valuable media.
IEEE Transactions on Circuits and Systems for Video Technology 19(8):1169-1171