Improved low frequency image adaptive watermarking scheme

In this paper we present extension of our low frequency watermarking scheme. We obtain a robustness improvement to most common image processing operations by embedding the watermark in the approximation image of die original image. in order to embed the watermark with minimum loss in image fidelity, die watermark strength is modulated according to the local image characteristics. We generate a visual mask based on the texture, edge and luminance masking effects of the human visual system. Experimental results show that the proposed technique is competitive with other watermarking techniques.