Stochastic dithering and watermarking

A new screen construction technique, which is described by means of a Maximum likelihood function as constraint of an iterative optimization procedure is introduced. Such stochastic screen function is spatially based, and is defined using the density function of a Markov point process. Further, a new high-capacity data embedding technique that focuses on exploiting the theory available for digital halftoning design, is also introduced. Such halftoning and watermarking scheme can be used in authentication and integrity verification applications as well as for general data embedding, where, digital signatures could be embedded into halftoned photos in a variety of identification documents. Being image independent, this new technique allows for imperceptible embedding such that no a priori knowledge is needed for recovery of inserted data.© (2001) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.