A secure and robust audio watermarking scheme using multiple scrambling and adaptive synchronization

In this paper, a novel highly confidential audio watermarking scheme using multiple scrambling is presented. Superior to other techniques, the new scheme is self-secured by integrating multiple scrambling operations into the embedding stage. To ensure that unauthorized detection without correct secret keys is nearly impossible, the following have been made. The watermark is encrypted by a coded-image; certain subbands are randomly selected from the total subbands for embedding and their order of coding is further randomised. In addition, adaptive synchronization is used to improve the robustness against hazardous synchronization attacks, such as random samples cropping/inserting, pitch-invariant time stretching and tempo-preserved pitch shifting. Our goal is to make the watermark impossible to be detected and robust even though the watermarking algorithm is open to the public. Experimental results of listening evaluation and robustness tests have demonstrated that the proposed scheme preserves transparent perception and also possesses strong resistance to typical attacks on audio watermarking.