A Random Coding Error Exponent for Joint Quantization and Watermarking of Gaussian Sources under Memoryless Gaussian Attacks

We study joint quantization and watermarking of a memory less Gaussian source under memoryless additive Gaussian attacks in a private scenario. The achievable region involving the quantization and the watermarking rate pairs has been established by Karakos and Papamarcou (2003). In this paper, we refine the analysis of the watermarking decoding error probability for given achievable rate pairs by deriving a computable random coding lower bound to the error exponent. The random coding exponent is positive within almost the entire achievable region of Karakos and Papamarcou.