B-DCT based Watermarking Algorithm for Patient Data Protection in IoMT Ersin Elbasi College of Engineering and Technology American University of the Middle East Kuwait ersin.elbasi@aum.edu.kw Abstract— Internet of Medical Things (IoMT) is the connection between medical devices and information systems to share, collect, process, store, and integrate patient and health data using network technologies. X-Rays, MR, MRI, and CT scans are the most frequently used patient medical image data. These images usually include patient information in one of the corners of the image. In this research work, to protect patient information, a new robust and secure watermarking algorithm developed for a selected region of interest (ROI) of medical images. First ROI is selected from the medical image, then selected part is divided equal blocks and applied Discrete Cosine Transformation (DCT) algorithm to embed a watermark into the selected coefficients. Several geometric and removal attacks are applied to the watermarked multimedia element such as lossy image compression, the addition of Gaussian noise, denoising, filtering, median filtering, sharpening, contrast enhancement, JPEG compression, and rotation. Experimental results show very promising results in PSNR and similarity ratio (SR) values after blocked DCT (B-DCT) based embedding algorithm against the Discrete Wavelet Transformation (DWT), Least Significant Bits (LSB) and DCT algorithms. Index Terms—Internet of Medical Things, watermarking, discrete cosine transformation, data protection. I. INTRODUCTION Internet of medical things (IoMT) is defined as communication between medical devices which is connected to the internet and share patient data such as text, image, and videos. IoMT can collect, generate, process, store, and analyses of medical data. It is real-time process and saves time for diagnosis and treatment. In addition to this, it provides security, privacy, and patient safety. Medical staff can see a patient’s full medical history and latest data and gets benefit from artificial intelligence to make robust decisions using IoMT. There are several types of medical devices that can be used in this system such as wearables, remote control machines, sensors, tracking systems, and computers. Also, we can categorize IoMT devices as in-home devices, in-hospital devices, and on-body devices. This kind of system will also help people to manage their own health. Protecting a patient’s privacy is an important issue in data sharing. Using IoMT, we can transfer any type of patient information from one place to another place. To solve the data privacy issue in health care we proposed a new watermarking algorithm based on blocked discrete cosine transformation. Watermarking is an embedding and extraction algorithm to hide data into multimedia elements such as image, video, audio, and animation. There are two main methodologies to embed data into the elements; the first one is the spatial domain watermarking and the second one is the frequency domain watermarking. Watermark can be directly embedded into the image pixels in the spatial domain which is not very strong against the geometric attacks. In frequency domain watermarking, first cover image is converted into the greyscale, then apply one of the frequency domains such as DWT, DCT, or Discrete Fourier Transformation (DFT), and then watermark can be embedded using the related algorithm. There are several works that have been done for watermarking; it depends on the cover image, watermark, application area, and quality of the images; all these methods have advantages and disadvantages. In this research work, we embed patient id number into the region of interest into the medical images using the block based DCT algorithm. Figure 1 shows the structure of the internet of medical things. Fig 1. Structure of Internet of Medical Things II. LITERATURE REVIEW Rathnayake et al. proposed a novel method to store, process, and integrate data that is received from the internet of medical things. High technology in the medical industry