Cryptographic system for medical image security using chaotic APFM nonlinear adaptive filter

In this paper, a novel cryptographic system for enhancing medical image security using chaotic amplitude phase frequency model (APFM) nonlinear adaptive filter is proposed. We set nine parameters, simulated time interval, and initial values for APFM nonlinear adaptive filter to generate chaotic orbits, and design a cryptographic system which could encrypt the medical images (plain images) to cipher images whose histograms are uniformly distributed. Furthermore, our encryption algorithm can successfully pass the NIST SP 800-22a tests. The proposed cryptographic system is shown to possess good cryptographic properties and large secret key space which is enough to resist all brute-force attacks.