Multi-bit informed embedding watermarking with constant robustness

This paper proposes an informed spread spectrum watermarking technique for the embedding of multi-bits into images using blind detection. The new technique exploits the information available at the embedder to eliminate all the interferences from the host, patterns and perceptual masking. A statistical analysis leads to the minimum embedding strength required by each pattern to achieve a specified bit error probability for a given additive noise distortion. As a result, each message bit will present the same degree of robustness. Experimental results illustrate the performance achieved for a set of typical valumetric attacks.