A Novel Color Image Encryption Algorithm Using Coupled Map Lattice with Polymorphic Mapping

Some typical security algorithms such as SHA, MD4, MD5, etc. have been cracked in recent years. However, these some shortcomings. Therefore, the traditional one-dimensional-mapping coupled lattice is improved by using idea of polymorphism this paper, and a polymorphic mapping–coupled map with information entropy developed for encrypting color images. Firstly, we extend diffusion matrix original 4 × into an n matrix. Then, Huffman employed to propose new pixel-level substitution method, which applied replace grey degree value. We employ select f(x) spatiotemporal chaotic system. The pseudo-random sequence more diversified homogenized. Finally, three plaintext images 256×256×3, “Lena”, “Peppers” “Mandrill”, are selected order prove effectiveness proposed algorithm. experimental results show that algorithm has large key space, better sensitivity keys images, encryption effect.