Audio Watermarking Based on LWT and QRD

Abstract

This chapter presents a blind audio watermarking method based on LWT and QR decomposition (QRD) for audio copyright protection [31]. In our proposed method, initially the original audio is segmented into nonoverlapping frames. Watermark information is embedded into the largest element of the upper triangular matrix obtained from the low-frequency LWT coefficients of each frame. A blind watermark detection technique is introduced to identify the embedded watermark under various attacks. Simulation results indicate that the proposed watermarking method is highly robust against different attacks. In addition, it has high data payload and provides good imperceptible watermarked sounds. Moreover, it shows better result than the state-of-the-art methods in terms of imperceptibility and robustness. In this chapter, a blind audio watermarking method based on LWT and QR decomposition (QRD) is proposed. The main features of the proposed method are: (i) it utilizes the LWT and QRD jointly; (ii) it uses Bernoulli map, containing the chaotic characteristic to enhance the confidentiality of the proposed method; (iii) watermark extraction process is blind; (iv) subjective and objective evaluations reveal that the proposed method maintains a high audio quality; and (v) it achieves a good trade-off among imperceptibility, robustness, and data payload. Simulation results demonstrate that the proposed watermarking method shows high robustness against various attacks such as noise addition, cropping, re-sampling, re-quantization, and MP3 compression. Moreover, it outperforms the state-of-the-art methods [9–10, 15–16, 20, 23, 24, 26, 29] in terms of imperceptibility, robustness, and data payload. The data payload of the proposed method is 172.39 bps, which is relatively higher than that of the state-of-the-art methods.