visual cryptography

Nowadays, unique identifiers are used to authenticate individuals. These identifiers are called biometrics with iris being one of the most popular ones. Research performed in this paper consist of designing a new identification system based on improved security in iris database. In this paper, we propose an iris template protection method based on Visual Cryptography (VC) and RSA. For iris template protection, the binary iris template is divided into two shares using VC, where one share is stored in the database and the other is kept with the user on a smart    card. In order to provide additional security, the share that is stored in the database is encrypted with RSA encryption. In the next step the patterns obtained from each image are compared with the patterns in the database and, by defining a threshold, the identification procedure is carried out. In this paper, the CASIA - v1 image bank has been used. The EER value after encryption is approximately 0.01. We then expose the system to different noises such as salt and pepper, white Gaussian noise and mean filt.r. After applying the noises, we haveit is observed that the system has shows been better performance compared to the than other systems which we have investigated.

Visual cryptography is one of the newest techniques is image encryption. Visual cryptography encrypts visual information and generates two or more shares which contain no information separately, but reveal the secret when superposed. The main advantage of this scheme is that the decoding process does not need any knowledge of cryptography and human visual system is able to decrypt the secret message. In this article, a new encryption method based on particle swarm optimization is provided. The basis matrices are obtained using this approach and then used for encryption. In previous work, a Genetic Algorithm based method was proposed. In our work we fix a subtle yet crucial bug in the GA based method which is generating pictures with negative contrast in some cases and propose a simpler alternative. Simulation results show that the proposed method meets all the initial conditions of visual cryptography while decreasing the number of function evaluations and can provide a contrast enhancement. Moreover, the proposed method has the advantage of being generic and can be used in various threshold based visual cryptography.