DWT-DCT-Based Audio Watermarking Using SVD

This chapter presents a DWT-DCT-based audio watermarking method using SVD and quantization [22, 23]. In the proposed method, initially the original audio signal is segmented into non-overlapping frames. DWT is applied to each frame and detail coefficients are represented in matrix form. DCT is performed on the detail coefficients and the obtained DCT coefficients are reshaped. SVD is applied to the reshaped DCT coefficients of each frame. Watermark information is then embedded into the highest singular value of each audio frame by quantization. Watermark information is extracted by comparing the largest singular value of original and attacked watermarked DCT coefficients obtained from the DWT sub bands of each audio frame. Experimental results indicate that our proposed watermarking method is highly robust against various attacks such as noise addition, cropping, resampling, requantization, and MP3 compression. Moreover, it outperforms state-of-the-art watermarking methods in terms of imperceptibility, robustness, and data payload. The SNR values of the proposed method range from 38 to 41 dB, in contrast to the state-of-the-art methods whose SNR values range from only 12 to 28 dB. In addition, the maximum bit error rate (BER) of the proposed method is 3.3203, whereas the maximum BER of the state-of-the-art methods is 51.73. Moreover, the data payload of the proposed method is 172.39 bps, which is relatively higher than that of the state-of-the-art methods.