Secure Quaternion Feistel Cipher for DICOM Images

Area of Science:

• Computer Science
• Cryptography
• Medical Imaging

Background:

• Digital imaging in medicine, particularly DICOM, requires robust security measures.
• Previous quaternion-based encryption methods had identified security vulnerabilities.
• Existing encryption standards like AES and 3DES may not be optimal for DICOM data.

Purpose of the Study:

• To propose an improved and extended quaternion-based lossless encryption technique for DICOM images.
• To address and rectify security flaws found in the prior Dzwonkowski et al. (2015) algorithm.
• To develop a secure and computationally efficient encryption method for medical image data.

Main Methods:

• Implementation of a secure quaternion Feistel cipher (S-QFC) using a modified Feistel network.
• Utilization of quaternion properties for 3D data rotations within cipher rounds.
• Introduction of a novel key generation scheme based on quaternion Julia sets.
• Application of both-sided modular matrix multiplications for encryption and decryption.

Main Results:

• The S-QFC algorithm successfully eliminates major security flaws of its predecessor.
• The proposed method demonstrates high computational speed compared to AES and 3DES in DICOM.
• Computer-based analysis and cryptanalysis confirm the algorithm's security and efficiency.
• Lossless encryption of DICOM images is achieved with enhanced security.

Conclusions:

• The S-QFC algorithm provides a significant advancement in securing DICOM images.
• This method offers a superior balance of security and computational performance for medical data.
• The developed technique presents a viable and secure alternative for medical image encryption.