Image Assisted Data Security using Key Encrypted File

Abstract

In this paper a new technique for image based data hiding with a binary file is proposed. In traditional methods the image based data hiding referred as steganography. The basic idea of Steganography is that it distributes the message uniformly throughout the image. But it will cause degradation to the image. In this paper the image based data hiding is performed using the binary file that ensures more security and confidentiality. Here the image is divided into blocks of equal sizes and the message is then embedded into the central pixel of the block using cyclic combination of 6 th , 7th, 8 th bit. The block of the image is chosen randomly using Array shuffling algorithm similar to pseudo random number generator seeded with an array shuffling key. In proposed method the image is divided into 256 blocks and the message is uniformly distributed in the image but there will be no change in the image pixels. The user keeps a secret binary file along with the image that contains the bits corresponding to the message. The binary file that contains bit values corresponding to the message will provides more security. The binary file is then encrypted with the same key or another key and converted to base64 encoding. And it is send to the receiver. The receiver can download the image from anywhere and the information about the image is shared by sending the URL or it may be known to the receiver. The array shuffling key is shared with the receiver by using any of the symmetric key exchange technique. Then receiver can retrieves the message by analyzing the binary file by decrypting and converting to normal utf-8 encoding from base64. In this method the image quality is maintained as such as the original image, ie the pixel value of the image does not changed. The main advantage is that it does not limit the size of message that can be distributed in the image. The message can be retrieved only with the help of image, binary file, and array shuffling key. So the security is assured.