Perceptual Image Hashing Using Feature Fusion of Orthogonal Moments

Due to the limited number of stable image feature descriptors and the simplistic concatenation approach to hash generation, existing hashing methods have not achieved a satisfactory balance between robustness and discrimination. To this end, a novel perceptual hashing method is proposed in this paper using feature fusion of fractional-order continuous orthogonal moments (FrCOMs). Specifically, two robust image descriptors, i.e., fractional-order Chebyshev Fourier moments (FrCHFMs) and fractional-order radial harmonic Fourier moments (FrRHFMs), are used to extract global structural features of a color image. Then, the canonical correlation analysis (CCA) strategy is employed to fuse these features during the final hash generation process. Compared to direct concatenation, CCA excels in eliminating redundancies between feature vectors, resulting in a shorter hash sequence and higher authentication performance. A series of experiments demonstrate that the proposed method achieves satisfactory robustness, discrimination and security. Particularly, the proposed method exhibits better tampering detection ability and robustness against combined content-preserving manipulations in practical applications.