A Fast Image Encryption Technique Using Henon Chaotic Map

Recent advancements in the networking technologies led to increase in network bandwidth, hence allowing transfer of files of large size. A major portion of files being transferred through various networks all over the world consists of multimedia data, particularly digital images. In this project, we propose a new image encryption scheme that may be used for securing the digital images. The scheme uses Henon chaotic map and 128-bit secret key in order to generate the cipher image. Henon chaotic map is a two-dimensional iterated discrete dynamic system that shows chaotic character on specific values of the constants used. Chaotic maps are very sensitive to the initial parameters, i.e., a slight change in the initial conditions drastically changes the overall output generated by the chaotic system. In our scheme, we use Henon chaotic map along with an externally supplied 128-bit secret key is used to encrypt the original image. After encrypting the image, pixel shuffling is performed using a permutation matrix generated using the chaotic map. The algorithm is tested on a standard set of images against various performance metrics like peak signal-to-noise ratio (psnr), entropy, histogram etc. The algorithm was found to be robust against plain-text, statistical attacks, chosen plain-text etc.