A REVIEW PAPER ON IMAGE AUTHENTICATION SCHEME

Image authentication is one of the methods which can detect the any tampering data. The original grayscale document image is converted into stego image by adding the alpha channel plane. The stego image is in the Portable Network Graphics (PNG) format. This stego image is transmitted over the network. The authentication process is applied on the stego image on the receiver side. In the authentication process the data extracted from this stego image is compared with the data computed from the binary version of the stego image. If the data is matched the image is considered to be authentic. Else the tampered blocks are marked and the image is self-repaired using inverse secret sharing scheme.but in other methods they cannot resist the selfsubstitution attack, the same-position-substitution attack, or the cut- off attack. Furthermore, those attacks can be completed by the popular image editing software Adobe Photoshop. We proposed security enhanced authentication scheme. Our proposed scheme is capable of repairing the content of the given stego-image if attacked by the methods mentioned above.