AES-RSA Watermarking for Robust and Secure Multimedia Protection in Medical Imaging Systems

Abstract

Purpose: To develop a secure, cryptographically enhanced digital watermarking technique for protecting the authenticity and ownership of medical imaging content shared in clinical environments.

Methods: A hybrid watermarking framework is proposed that integrates Advanced Encryption Standard (AES-256) and RSA-based digital signatures with Discrete Wavelet Transform (DWT) domain embedding. The watermark, encrypted with AES in Cipher Block Chaining (CBC) mode, is embedded into the LH sub-band of medical images, and a digital signature ensures authentication. The method is evaluated on standard test images and medical image formats (e.g., DICOM) for imperceptibility and robustness using metrics such as PSNR and NC.

Results: The proposed method achieved PSNR > 42 dB and NC > 0.96 against attacks including JPEG compression, noise, and cropping. Comparisons with prior methods show superior imperceptibility and robustness, highlighting suitability for secure radiology data sharing, PACS integration, and clinical documentation.