WATERMARKING PARAMETRIC REPRESENTATIONS FOR SYNTHETIC AUDIO

This paper proposes to watermark parametric representa-tions for synthetic audio. Our watermark system combines quantization index modulation at the encoder and maximum likelihood parameter estimation at the decoder. To guaran-tee error-free data hiding under expected types of attacks, knowledge of Fisher information and Cramér-Rao bounds is applied to the system design. Experiments show that, merely by quantizing the frequency of sinusoidal tones, one can achieve 50b/s of data hiding that is robust to perceptu-ally shaped additive attacks such as an MP3 compression. 1