Audio Watermarking Based on Wavelet Transform and Quantization Index Modulation

In this paper, we present a technique for embedding digital watermarks into digital audio signals. Watermarking is a technique used to label digital media by hiding copyright or other information in the underlying data. In the case of digital audio, the main constraint is the tradeoff between robustness and imperceptibility, as hearing is one of the most sensitive human senses. In our method, the audio host signal is divided into several frames; each of these frames is decomposed using a wavelet transform. To the wavelet coefficients we apply distortion compensated (DC) quantization index modulation (QIM). For additional security we use dither modulation (DM). As a result, for our proposed method the watermarked host signal has good quality, and is robust over common attacks such as MPEG1 layer 3 (mp3 compression), low pass filtering, white noise and echo.