C9. Chaotic encryption of images in the Fractional Fourier Transform domain using different modes of operation

This paper presents an implementation of 2-D chaotic Baker map using different modes of operations after applying the Fractional Fourier Transform (FrFT) on digital images. The proposed image cryptosystem implements the chaotic Baker map scrambling using three different modes of operation; Cipher Block Chain (CDC), Cipher Feed-Back (CFB), Output Feed-Back (OFB), in which the Initialization Vector (IV) works as the main key. We examine its implementation for digital images along with its detailed security analysis. The security analysis includes the statistical analysis, the histogram analysis, the correlation coefficient metric, the maximum deviation metric, the irregular deviation metric, the noise immunity, the processing time, and the key space analysis. Experiments and results verify and prove that the proposed image cryptosystem is highly secure from the cryptographic viewpoint, more immune to noise, has high key sensitivity, and takes less processing time.