We proposed a novel content-based image semi-fragile watermarking algorithm for authentication in finite ridgelet transform(FRIT)domain.The authentication watermark was generated according to the image feature which was the mean of an image extracted from FRIT.The watermark was embedded in the FRIT coefficients which were selected by adopting minimizing Bayesian risk estimate.Experimental results show the algorithm is simple and effective,it can provide very good classification of malicious tampering and in...