Abstract— In the current digital era, the rapid exchange and transmission of medical images, particularly CT-Scan images, have heightened concerns about data security and privacy. This paper presents a robust digital watermarking method designed to protect sensitive patient information in CT-Scan images. The proposed approach integrates Discrete Wavelet Transform (DWT) and Singular Value Decomposition (SVD) with QR Code-based Visual Cryptography and hybrid RSA-AES encryption. The method begins by embedding the watermark in the high-frequency sub-bands of the image using DWT-SVD. The watermark, encrypted with AES and further secured by RSA encryption of the AES key, is converted into a QR code and scrambled using a Chaotic Logistic Map. This hybrid approach ensures data confidentiality, robustness, and resilience against various image processing attacks such as noise addition, cropping, scaling, and JPEG compression. Experimental results demonstrate high image quality, with an average PSNR of 37.9dB, and significant resistance to common attacks, validating the effectiveness of the proposed method in maintaining both security and image integrity.

Keywords— Digital Watermarking,QR Code,DWT-SVD, RSA,AES,Visual Cryptography,CT-Scan Images