A Topology for Fingerprint Image Encryption based on HDWT-SVD and Hyperchaos

The topology of an encryption algorithm that offers a fast and robust security of fingerprint images as they transit in porous transmission channels is presented. Pixels of fingerprint images were mapped with sequences generated from a logistic chaotic map and shuffled bidirectionally, before they were diffused by structured sequences generated by a hyperchaotic system. The diffused pixels were subsequently decomposed using the singular value decomposition technique (SDV). The SVD- decomposed image was further decomposed using 2D Haar wavelet transforms. The wavelet-decomposed image and new sequences generated from the hyperchaotic system are processed via bitwise XOR operations, which resulted in the final encrypted image. Cryptographic analyses such as correlation analysis, key and plaintext sensitivity tests, and entropy test on fingerprint images showed that the algorithm is efficient and robust against cryptographic attacks.