Spatial watermark for image content authentication

摘要

This paper is focused on digital image authentication, considered as the process of evaluating the integrity of image con- tents relatively to the original picture and being able to detect, in an automatic way, malevolent content modifications. A computationally efficient spatial watermarking technique for authentication of visual information, robust to small distortions caused by compression, is described. In essence, content-dependent authentication data are embedded into the picture, by modifying the relationship of image projections through out the entire image.