A novel chaotic image encryption algorithm based on water wave motion and water drop diffusion models

This paper will put forward a novel chaotic image encryption algorithm with confusion–diffusion architecture. First of all, secret keys will be processed by key generator before they can really be used in the encryption scheme, and in this stage this paper associates plain image with secret keys; Secondly, by imitating the trajectory of water wave movement, encryption algorithm will do scrambling operations to the image. Thirdly, this paper combines water drop motion and dynamic look up table to realize diffusion operations. For an 8 bits pixel, this algorithm will just dispose the higher 4 bits, which is because the higher 4 bits contain the vast majority of information of the image. At last, the experiment results and security analysis show that this proposed algorithm has a desirable encryption effect. Its key space is large enough, it is sensitive to keys and plain image, its encryption speed is fast and it can resist cryptanalysis such as brute attack, differential attack, etc.