Digital watermarking of medical image using ROI information

Recently, the medical image has been digitized by the development of computer science and digitization of the medical devices. There are needs for database service of the medical image and long term storage because of the construction of PACS (Picture Archiving and Communication System) following DICOM (Digital Imaging Communications in Medicine) standards, telemedicine, and et al. Furthermore, authentication and copyright protection are required to protect the illegal distortion and reproduction of the medical information data. In this paper, we propose digital watermarking technique for medical image that prevents illegal forgery that can be caused after transmitting medical image data remotely. A wrong diagnosis may be occurred if the watermark is embedded into the whole area of image. Therefore, we embed the watermark into some area of medical image, except the decision area that makes a diagnosis so called region of interest (ROI) area in our paper, to increase invisibility. The watermark is the value of bit-plane in wavelet transform of the decision area for certification method of integrity verification. The experimental results show that the watermark embedded by the proposed algorithm can survive successfully in image processing operations such as JPEG lossy compression.