Adaptive Watermarking for Digital Colored Images based on the Energey of Edges

Watermarking is a digital technology that is used to prove copyrights ownership and ensure authenticity for multimedia products. In this paper, we present an adaptive spatial domain watermarking algorithm for colored images. This algorithm depends on choosing the color layer with maximum edge energy to embed the watermark in it. The watermark pixels are scrambled together with the blocks of the selected color using two different keys which gives double uncertainity that makes the watermark damaging a very difficult process. The embedding process is adaptive and it takes into consideration the nature of the images and the human visual system. The results prove that our method is very robust and it manages to survive several intentional and unintentional attacks. Also, the quality of the image is preserved as the average value of the peak signal to noise ratio (PSNR) exceeds 70 dB.