Structural Obfuscation and Crypto-Steganography-Based Secured JPEG Compression Hardware for Medical Imaging Systems

In modern healthcare technology involving diagnosis through medical imaging systems, compression and data transmission play a pivotal role. Medical imaging systems play an indispensable role in several medical applications where camera/scanners generate compressed images about a patient's internal organ and may further transmit it over the internet for remote diagnosis. However, tampered or corrupted compressed medical images may result in wrong diagnosis of diseases leading to fatal consequences. This paper aims to secure the underlying JPEG compression processor used in medical imaging systems that generates the compressed medical images for diagnosis. The proposed work targets to secure the JPEG compression processor against well-acknowledged threats such as counterfeiting/cloning and Trojan insertion using double line of defense through integration of robust structural obfuscation and hardware steganography. The second line of defense incorporates stego-key based hardware steganography that augments the following: non-linear bit manipulation using S-box (confusion property), diffusion property, alphabetic encryption, alphabet substitution, byte concatenation mode, bit-encoding (converting into stego-constraints) and embedding constraints. The results of the proposed approach achieve robust security in terms of significant strength of obfuscation, strong stego-key size (775 bits for JPEG compression processor and 610 bits for JPEG DCT core) and probability of coincidence of 9.89e-8, at nominal design cost.