On the security of singular value based watermarking

The advantage of the singular value (SV)-based image watermarking approach is its robustness to distortion attacks. In this paper, we provide a mathematical proof as to why SV-based watermarking algorithms are robust to small distortion attacks of any type. The same mathematical proof also confirms that such watermarking schemes unfortunately suffer from false watermark detection as long as the distortion attacks are small. Thus a false watermark (not the embedded one) can be detected from a watermarked image that is not severely distorted. SV-based watermarking methods cannot thus be used for protecting the image ownership.