Aiming at the edge blurring manipulation in image tampering,a new algorithm for image forensics is presented. In this algorithm,first,the tampered blurring edge is enhanced based on the fuzzy mathematics,while the real clear edge and flat region is weakened,thus obtaining an image. Next,the tampered image is divided into many sub-images,which are then classified to remove flat regions and real clear sharp edges by using the attribute
reduction of rough set theory,thus obtaining another image. Finally,a fusion of the two above-mentioned images is performed to obtain the resulting image. Experimental results show that the proposed algorithm is an effective passive forensics method that reveals the blurred regions but excludes flat regions and real clear sharp edges.