Pattern-Based Blind Spatial Image Watermarking

In this paper, we propose an original pattern-based blind spatial image watermarking scheme. The pattern is generated via a key-vaulted operation on the original watermark image block, and then modified with a secret position key before it is inserted into the designated position. The strength of its robustness depends on two factors: one is the scale factor when added with the host pixels, and the other is the number of patterns to be inserted. Part of the position key can be public for detection, while the other keys must be kept secret for ownership proof or resistance to removal attack. Theoretical analysis on tradeoff between the capacity and the robustness is also presented. Experimental results have shown that this scheme bear stronger robustness than traditional spread spectrum scheme under the same conditions, while simultaneously with extra security features.