ROI-based tamper detection and recovery for medical images using reversible watermarking technique

Digital image watermarking is proposed to overcome the problems of security, capacity and cost in health care management systems. Medical images, unlike most of images, require extreme care when embedding additional data within them because the additional information must not affect the image quality and readability. In order to overcome any misdiagnose caused by embedding data into medical images, lossless data hiding techniques have been developed. This paper presents a lossless watermarking technique for Ultrasound (US) images. The proposed technique adopts a high-capacity reversible data hiding scheme based on difference expansion (DE). It can be used to hide patient´s data hiding and protecting the region of interest (ROI) with tamper detection and recovery capability. The experimental results show that the original image can be exactly extracted from the watermarked one in case of no tampering. In case of tampered ROI, tampered area can be localized and recovered losslessly.