Effective watermarking based on energy balancing in audio signals

Techniques based on discrete cosine transform (DCT) have been proposed for digital watermarking of audio signals; however, the watermark is susceptible to MP3 compression. This paper presents an effective audio watermarking technique based on energy balancing of DCT coefficients to recover the watermark from signal processing, such as compression, without compromising the intended effect of the original signal. The presented technique needs to divide the audio signal into segments. Three parameters define the segment length, what segments are selected, and the frequency range of DCT of the selected segments for watermark embedding, respectively. The error-correcting code can be incorporated to improve the decoded watermark quality. Experimental results show that the technique is robust against compression and other operations. Furthermore, no original signal is required for decoding the watermark.