Image Authentication Resilient to Translation, Rotation and Scaling

This paper presents an image content authentication algorithm resilient to geometric and some general operations. The original image is normalized into a standard prototype form according to the blind normalization arithmetic, and then the smooth-component and the edge-character are drawn from the prototype image with the dyadic wavelet transform multi-scale edge detection. After coded with 64 bits, the smooth-component along with the serialized edge-character is embedded in the original image as watermark. When verifying an image, the same feature is computed and the results are compared with the watermark extracted from the test image to confirm whether the content has been tampered. The experiments prove that this authentication algorithm can effectively detect the vicious tamper. Moreover it can tolerate not only the distortion produced by compression, filter and some other image processing but also the geometrical transformations.