Analysis of the moment based image normalization effects on watermarking capacity in DCT and DWT domains

The goal of this study is to investigate how the moment based image normalization procedure that is used to increase robustness of a digital image watermark especially for geometrical attacks affects the capacity of a digital image watermarking algorithm. For this purpose, watermark was inserted in discrete cosine and wavelet domains with and without normalization. Then, several attacks were performed on the watermarked images and the capacities of the resulting distorted images were estimated by using the statistical approach proposed by Moulin and Mihcak. Simulations show that the discrete wavelet transform always outperforms the discrete cosine transform.