Phase-Signature Based Watermarking for Multimedia Authentication: Analysis and Design

In this work, we address phase-signature based digital image watermarking. The signature is extracted from the Fourier phase information of the digital media. It is then embedded in the Fourier magnitude spectrum. The detection and/or authentication is based on the well established area of phase-only filter based correlation techniques in the optics community. We propose to analyze the distortion coming out of the embedding process, model it, and eventually parameterize it so that optimal embedding can be done by trading off with other aspects of watermarking. It will be shown why permutation like functions facilitate the signature embedding process by minimizing the embedding degradation.