Hybrid multimodal medical image fusion and secure watermarking for smart healthcare

The transfer of patient information in a networked health care system raises significant security issues, including unauthorized access, tampering, and unauthorized use. Most of the techniques have shown limited performance in terms of robustness, imperceptibility, and high embedding capacity simultaneously. Thus, to overcome these problems, this research has introduced a robust watermarking scheme for smart health care. The method proposed in the paper follows a hybrid approach, combining concepts of visible and invisible watermarking, multimodal image fusion, and encryption to enhance the system's reliability and security. First, the hospital logo is inserted as a visible watermark in the carrier image. Then, the CT and MRI images are fused together through the hybrid NSST-DTCWT approach to create the medical watermark. To improve efficiency, PCA is applied to the visibly watermarked carrier image. The fused watermark is then inserted into the system using the NSST and SVD approaches, focusing on low-energy areas to achieve high imperceptibility and robustness. The process is then followed by the encryption process for the watermarked image. The extensive experimental evaluation and comparison confirm that the proposed framework possesses excellent adaptability, robustness (Average NC[Formula: see text]), and embedding efficiency, with high visual quality (Average PSNR and SSIM of 44.7122 dB and 0.9955, respectively). The results' findings indicate that the proposed watermarking technique is effective for tackling the security, transparency, and robustness concerns in medical image communication, thereby making it a feasible and clinically applicable tool in smart healthcare applications.