Fridrich Structure Implementation on Gray Scale Images in an Embedded FPGA Platform

These days, a countless number of digital images are made in many fields, such as military, medicine, education, and personal affairs. As digital images usually contain secret or private data, image encryption has grown into a hot issue in theoretical study and in its practical presentation. In this paper an image encryption algorithm based on Logistic map will be used. Contrasting most of the existing image encryption algorithms, the proposed algorithm gives the original image as an integer pixel, and uses Logistic map for confusion and Galois field LFSR for diffusion. The consumption of logistic map and Galois field LFSR makes the proposed algorithm achieves not only a desirable level of security, but also high effectiveness, so the algorithm is suitable for practical application. Apart from this, the algorithm accepts a "confusion-diffusion-confusion" structure to yield good confusion and diffusion things which are the goods of the operation of a secure cipher. Simulation results and security analysis advice that the proposed algorithm has many desirable things of a perfect cryptosystem, thus it is very suitable for practical applications. The security analyses performed are Histogram analysis, Correlation analysis, Entropy analysis, Encryption Quality analysis, Differential analysis, Error metric analysis.