This section is presented the essential researches about medical image security. The watermarking schemes were reported by many researchers recently to secure the medical image [30]. Arunkumar et al. [1] has been proposed a method of nonblind and hybrid domain medical image watermarking by using different transforms like singular value decomposition (SVD), redundant integer wavelet transform (RIWT), and discrete cosine transform (DCT). A patient’s information is embedded in the medical image’s hybrid coefficients in this scheme based on additive watermarking. The robustness and good imperceptibility have been achieved with this scheme based on the experimental results. In [20], a watermarking scheme based encryption is proposed using IWT and the least significant bit (LSB) substitution. In [19], a model is proposed for medical image security in telemedicine applications.
In [27], a multi-layer watermarking scheme is proposed based on the hybridization of SVD, DCT, DWT, and chaotic encryption. The encoding of a watermarked medical image is done through chaotic encryption in this scheme after inserting watermark data into it. In [3], a method of quartic digital signature-based medical image authentication is proposed. In [26], a robust watermarking scheme is presented with the implementation of DWT and DCT. Under this scheme, the medical image is categorized into two parts, like the region of non-interest (RONI) and the region of interest (ROI). After that, the watermark is embedded into RONI hybrid coefficients of the medical image.
In [26], a scheme of robust and multiple-layer watermarking is proposed with the use of SVD, redundant discrete wavelet transform (RDWT), non-subsampled contourlet (NSCT), and chaotic encryption. In telemedicine applications, this scheme is used by inserting three encrypted watermarks into the medical image to provide security for medical images. In [29], a fragile watermarking scheme was introduced based on NSCT, and Compressive Sensing (CS) based encryption on authenticating the medical image. In [6], a watermarking scheme was considered using CS-based encryption and DCT for tamper detection in the medical image.