The identification of copy-paste forgery image is to find the suspicious region via pixel-by-pixel or block-by-block match

the computation costs is very heavy. An efficient blind forgery image detection approach based on scale-inva- riant feature transform (SIFT)is proposed in the paper

which employs SIFT keypoints for positioning the initial suspicious forgery region. The asymmetric search is exploited for refining the suspicious region and determining the forgery area. Experiments demonstrate that the proposed algorithm could significantly decrease the number of candidate search block

accurately identify the copy-paste forgery region regardless of the existence of gauss

salt and pepper noise

and the computational cost is reduced by 1~2 orders of magnitude with compare to the conventional methods.