A novel quantization watermarking scheme by modulating the normalized correlation

This paper presents a novel quantization based watermarking scheme. Watermark embedding is performed through modulating the normalized correlation between the host vector and a random vector with dither modulation. The watermarked signal is derived to provide the modulated normalized correlation in the sense of minimizing the embedding distortion. The proposed scheme is theoretically invariant to valumetric scaling and can resist stronger noise than the well-known spread transform dither modulation. Numerical simulations on real images show that it achieves the good imperceptibility and strong robustness against a wide range of attacks.