Document image watermarking based on weight-invariant partition using support vector machine

Abstract

Security concern about document images is important since document images are distributed in large amount both electronically and physically. They are easily copied and the copyright information is difficult to identify. In this paper, we present a new algorithm for document image watermarking, which is based on weight-invariant partition of the document in the spatial domain, where the weight of a partition is the average number of pixels in lines within the partition. We discuss the issues of robustness, security, capacity and fault-tolerance related to the watermarking method. In order to simultaneously achieve high capacity and security, the partition method is further improved using the support vector machine technique. The experiments indicate the soundness of our method. © Springer-Verlag 2004.