We propose a new multipurpose audio watermarking scheme in which two complementary watermarks are used. For audio copyright protection, the watermark data with copyright information or signature are first encrypted by Arnold transformation. Then the watermark data are inserted in the low frequency largest significant discrete cosine transform (DCT) coefficients to obtain robustness performance. For audio authentication, a chaotic signal is inserted in the high frequency insignificant DCT coefficients to detect tampered regions. Furthermore, the synchronization code is embedded in the audio statistical characteristics to resist desynchronization attacks. Experimental results show that our proposed method can not only obtain satisfactory detection and tampered location, but also achieve imperceptibility and robustness to common signal processing attacks, such as cropping, shifting, and time scale modification (TSM). Comparison results show that our method outperforms some existing methods.

关键词： Audio watermarking,  Copyright protection,  Content authentication,  Compound encryption,  Synchronization