Keypoint Extraction Using SURF Algorithm for CMFD

Copy-move forgery is a specific type of image tampering where a part of the image is copied and pasted on another part generally to conceal unwanted portions of the image. Hence, the goal in detection of copy-move forgeries is to detect image areas that are same or extremely similar. In this paper we propose a new approach which can efficiently identify the copy move forged areas. For achieving the copied image area first segment the image that is the test image is segmented into different independent patches. These patches are evaluated based on their matching and then the copied images are identified. For patch matching a two level of matching is carried out. In the first stage suspicious pairs of matches is obtained and affine transform matrix is roughly estimated. In-order to confirm the existence of copy move forgery a second level of patch matching with respect to Expectation Maximization algorithm is used. Thus the copy move forged areas are identified.