Reversible Watermarking for the Security of Medical Image Databases

Medical images of different modalities are produced on a daily basis in the medical centers around the globe. The same is transmitted over the Internet to other medical practitioner to get the second opinion from doctors located in remote areas. Numbers of issues are raised with this transmission of medical information, for example, authenticity and confidentiality of medical information. To overcome these important issues, a medical image watermarking system has been proposed which first segments the input medical image into a region of interest (ROI) and region of non interest (RONI) areas. Later it implants two different watermarks in ROI and RONI. The first watermark is fragile watermark which is a binary pattern and is inserted in ROI and the other is robust watermark which is the composite watermark and is inserted in the RONI. The simple Least Significant Bit (LSB) substitution technique is employed for casting the watermarks. CT scan medical images are used for experiments. The simulation results reveal that proposed system provides better security of medical images as well addresses both the issues of authenticity and confidentiality.