Tuijin Jishu/Journal of Propulsion Technology ISSN: 1001-4055 Vol. 44 No. 4 (2023) __________________________________________________________________________________ 5584 A New Approach for Roni Based Medical Image Watermarking Using Contourlet Transform J. Jensy Rajakumari, Dr. G. Murugeswari 1 Department of Computer Science and Engineering Manonmanium Sundaranar University, Tirunelveli 2 Department of Computer Science and Engineering Manonmanium Sundaranar University, Tirunelveli Email: jjensydiaz@gmail.com, gmurugeswari@msuniv.ac.in Abstract The majority of modern healthcare systems rely their diagnoses on data collected from the internet. The medical imaging and patient health records are transmitted over the network via the internet-enabled healthcare (E-health) applications. In practical medical applications, the primary problem is the security of medical images transmitted over the internet. For the purpose of embedding secret data on medical images without affecting important information, a trustworthy watermarking approach is required. We provide a unique watermarking approach in this research that embeds the watermark data in the medical image's Region of Non- Interest (RONI). The medical image is subjected to a contourlet transform, and RONI is determined using contourlet coefficients. In this work, we demonstrate the embedding and extraction process of medical image watermarking using Contourlet transform. Experiments are carried out on medical images such as MRI and CT images. The performance of the proposed scheme is analyzed using the metric PSNR. The proposed scheme provides an average PSNR value of 47.1604% for MRI images and 57.5452% of PSNR for CT images. Keywords: Medical Image, Watermarking, Contourlet Transform, RONI, Image Security. 1. Introduction Over the decades, the development of technology is increasing day by day. Thousands of multimedia data is transmitted over internet every day. Data security and quality are the major concerns in data transmission. In the medical field also, transmission of medical images through internet without losing any information is the challenging task. The increasing number of medical images in the medical field needs to be shared among specialists and hospitals. The sharing of medical images through internet among hospitals requires privacy. Security of medical information implies three main qualities. They are (i) Confidentiality, (ii) Reliability and (iii) Availability. In Confidentiality, the information which is transmitted must be accessible by the owners only. (ii) Reliability has two aspects. (a)Integrity and (b) Authentication. Integrity means the information must not be modified by unauthorized users. Authentication means the proof that the information belongs to the correct users. (iii)Availability is the ability of the information to be used by the owners in the normal scheduled condition of access and exercise.