Geometric Invariant Semi-fragile Image Watermarking Using Real Symmetric Matrix

In order to improve the detection of malicious tampering images, it is necessary to decrease the fragility of hidden watermarks, even for digital images which have been incidentally distorted. In this paper, we propose a new invariant semi-fragile digital watermarking technique based on eigenvalues and eigenvectors of real symmetric matrix generated by the four pixel pairs. A signature bit for detecting the malicious tampering of an image is generated using the dominant eigenvector. And the multi-rings Zernike transform (MRZT) is proposed to achieve geometric invariance. The MRZT method is to the geometric distortions even when the image is under malicious attacks. Experimental results show that this algorithm can resist high quality JPEG compression, and improve the detection performance of various malicious tampering. Key-Words: fragile watermarking, Eigenvalue, Geometric invariance, Zernike moment