In this paper, a new image authentication scheme based on quadtree segmentation is presented. In this scheme, partial digital signature encryption is employed to ascertain the origin of the image. Furthermore, the quadtree structure is imposed on the design of the authentication code. The authentication code consists of the quadtree list and the mean values of the quadtree leaf nodes. The size of the authentication code is adaptively determined according to the image characteristics. In the experiments, JPEG and JPEG2000 lossy compression and malicious manipulations are employed to evaluate the validity of the proposed scheme. The experimental results show that this scheme permits some acceptable operations and can detect malicious manipulations. Furthermore, when a malicious manipulation is detected, the mean values of the quadtree leaf nodes can be applied to recover the manipulated areas.
