Secure Hybrid Robust Watermarking Technique for Medical Images

Abstract

The protection of data is of at prime urgency in the medical field to boost the telemedicine applications. There is a need of robust and secure mechanism to transfer the medical images over the Internet. The proposed watermarking method is based on two popular transform domain techniques, discrete wavelet transforms (DWT) and discrete cosine transform (DCT). In the embedding process, the cover medical image is divided into two separate parts, region of interest (ROI) and non region of interest (NROI). For the identity authentication purpose, multiple watermarks in the form of image and text are embedding into ROI and NROI part of the same cover media object respectively. In order to enhance the security of the text watermark, Rivest-Shamir- Adleman (RSA) encryption technique is applied to the text watermark before embedding and the encrypted EPR data is embedded into the NROI portion of the cover medical image. The performance of the proposed method is evaluated for signal processing attacks and the desired outcome is obtained without significant degradation in extracted watermark and perceptual quality of the watermarked image.