Scale Invariant Digital Color Image Encryption Using a 3D Modular Chaotic Map

Cryptography is one of the most important security mechanisms for transmission digital media on Internet. Most proposed cryptographic image methods based chaotic maps are dependent upon sizes and them worked square images. In this paper tackling problem, a scale-invariant color encryption method in three-dimensional space presented. At first, two-dimensional converted into space, case, red, green, blue spectrums divided set gray-level sub-images. Then, to have confusion diffusion properties, 3D substitution permutation operation performed operations, pixel values sub-images changed with help XOR circular shift operators appropriate keys. operation, position pixels using modular chaos mappings. To permutation, or more windows equal size, then map operations each window separate Depending number sub-images, there may be two last that overlapping. increase speed encryption, steps can implemented parallel. The approach relative similar algorithms increases key improves standard parameters, such as entropy, sensitivity, adjacent correlations, histogram uniformity.