Robust reversible audio watermarking based on high-order difference statistics

Abstract

This paper proposes a robust reversible audio watermarking scheme by introducing a high-order difference statistical model. In the proposed scheme, the high-order difference statistical model is constructed to compute a statistical histogram. The histogram can be regarded as a robust feature and shifted for embedding a watermark sequence. Firstly, an original audio file is divided into a number of frames, then a high-order difference statistic in a frame can be calculated to construct a histogram of the high-order difference statistics. With a hiding key, the watermark can be embedded into the audio file by shifting the histogram. In the process of watermark extraction, with the hiding key, the watermark can be correctly extracted from the shifted histogram. Furthermore, by using the inverse operation of histogram shifting, the original audio file can be restored non-destructively. In addition, the watermark can still be correctly extracted from the watermarked audio file that is attacked by some signal processing operations to some extent, such as MP3 compression of 48 Kbps and Gaussian noise of 25 dB. Compared with the existing several robust reversible audio watermarking schemes, the proposed scheme has better performance in audio quality and robustness. Experimental results have shown the effectiveness of the proposed scheme.