Novel Binary Document Image Watermarking Exploitingthe Features of Double Domains

Abstract

This paper presents a double domain watermarking scheme for binary document image. The watermark patterns are generated as the discrete cosine transform (DCT) domain signals, and then perceptually shaped through weighting its components in the spatial domain with the perceptual masks. The perceptual masks are obtained by applying a psychovisual model in the spatial domain and simultaneously considering the impact of the distance between two flappable pixels. Watermark extraction can be operated by applying a correlation based detector in either of the two domains. The approach exploits the information of the two domains for embedding, but avoids transforming the original binary image directly, which does not cause unacceptable loss of watermark. The experimental results show that the presented approach performs very well both in invisibility and robustness.