Shape-based features for image hashing

Perceptual hashing is a solution for identification and authentication of multimedia content. The key of this technique is the extraction of proper features. In this paper, two features are proposed for natural image hashing. They are based on the description of shapes, in terms of contours and regions. The contour-based feature is formed by edge detection. The region-based feature is formed by the angular radial transform. Simulation results show that they have good robustness and discriminability. Compared to some other features, better ROC performance is achieved.