Capturing-resistant audio watermarking based on discrete wavelet transform

In this paper, we propose a wavelet-based audio watermarking algorithm that is robust against capturing attack. With a commercial capturing tool, it is possible to capture various audio contents without noticeable degradation, and thus can potentially facilitate the illegal distribution of the audio content. By adjusting the mean value of the lowest subband coefficients of the discrete wavelet transform (DWT) of the audio, the proposed watermark can survive capturing attack including sampling rate conversion, random cropping and compression. By incorporating a simple human auditory model, the inaudibility of the watermark achieved, and the detection probability is improved based on the difference information of extracted values. This is confirmed by experimental results.