Introducing A New Method for Estimation Image Complexity According To Calculate Watermark Capacity

One of the most important parameters in evaluating a watermarking algorithm is its capacity. In fact, capacity has a paradoxical relation with other two important parameters: image quality and robustness. Some works have been done on watermarking capacity and a few on image complexities. Most works on watermarking capacity is based on information theory and the capacity values which are calculated based on these methods are very tolerate. In this paper we propose a new method for calculating image complexity based on Region Of Interest (ROI) concept. After that we analyze three complexity measures named: Image compositional complexity (ICC), Quad tree and ROI method, with three different watermarking algorithms that are in Spatial, DCT and Wavelet domain to find a relation between complexity and capacity. Our experiments on 200 images show that the proposed ROI measure has the best adoption with watermarking capacity based on a visual quality degradation calculated by MSSIM. In addition, we found that there is an interesting arbitrary linear relation between watermarking capacity in bit per pixel with image complexity. This will open a new trend in calculating capacity of images based on their content