A new document watermarking algorithm based on hybrid multi-scale ant colony system

Abstract

This paper proposes and tests an improved method for a document image watermarking system. We first introduce a novel robust document image watermarking algorithm based on the concept of the weight-invariant partition in the spatial domain. The improvement of the proposed technique lies in reduction of the involved image partition problem to a combinatorial optimization problem. To solve this optimization problem, we propose a new hybrid multi-scale ant colony algorithm. The experimental results demonstrate the effectiveness of the improved method, especially that the resulting partitions are more secure and can lead to higher capacity. © Springer-Verlag 2004.