A medical image watermarking scheme based on dual-tree wavelet transform

A combined dual-tree transform wavelet (DT-CWT) and Bivariate Shrinkage for medical image watermarking is proposed in this paper. For this suggested approach, security issues for medical information and technical solution to protect these data in medical information are examined. A solution is proposed, which consisted in watermarking image areas that are not relevant for the diagnosis. The main part of this paper is devoted to exploit the exceptional quality of DTT combined with Bivariate Shrinkage with Local Variance Estimation at the extracted step of the watermark in the medical images. The experimental results showed much improved performance of the proposed technique for DT-CWT in comparison with DWT. The system is transparent to the user and allows image integrity control, in addition, it provide information on the location of potential alterations and evaluation of image modifications which is of major importance in medico-legal frame work. In addition the proposed scheme presented a flexible robustness against and favorably preserves the visual quality.