This paper presents a new image content authentication algorithm based on image feature for effectively authenticate the tampered image. First the smooth-component and edge-character are drawn from the image with the dyadic wavelet transform multi-scale edge detection

which form an image feature set for generating the digital signatures. This can ensure the one-to-one mapping relationship between the feature set and the image

and avoid the counterfeit attack. After 32 bits coding

the smooth-component is embedded in the original image with the edge-character as watermark. When the image is verified

the smooth character and edge character are compared to confirm whether the content has been tampered. The experiments prove that this authentication algorithm can effectively detect the event and the location of vicious tamper

and it can also tolerate the damage produced by compression

filter and some other image procession. Even if the image is degraded by some noise

it can still pass through the authentication correctly.