Cryptanalysis of a Digital Watermarking Scheme Based on Support Vector Regression

This paper analyses an image watermarking scheme based on Support Vector Regression (SVR) proposed by R. Shen et al. We describe various attacks against this scheme and show that watermark tampering can be done even when one does not know the secret key used to embed the watermark. Next we discuss methods to extract the keys used in the scheme under various usage scenarios. Our results show that Shen et al.´s scheme is not secure.