A solution to the watermark detection problem based on Bayesian estimation and EM algorithm

We have recently discussed digital watermarking techniques based on modifying the spectral coefficient of an image, and have presented a model of the watermark embedding and extracting processes and a model of watermark distortion caused by image processing and attack of watermarked images. In this paper, based on these models, we formulate the watermark detection problem as a kind of blind deconvolution problem. Then, as a solution to this problem, we propose a watermark detection method using Bayesian estimation and EM algorithm.