Multi-level security of medical images based on encryption and watermarking for telemedicine applications

In this paper, a robust and hybrid domain watermarking scheme is proposed for the security of medical images in telemedicine applications. The secret identity of the patient is inserting into the cover medical image using the hybridization of ridgelet transform and singular value decomposition for the purposed of identification and authentication. For better security of watermarked medical image, the Arnold scrambling based encryption is applying to it before sending it at the receiver end. The main advantage of this scheme is multi-level security where secret patient information is inserted to cover medical image to get a secure watermarked medical image using watermarking. Then, encryption is applied to the watermarked medical image to generate its encrypted version. Thus, this proposed scheme provides multi-level security using watermarking and encryption. The advantage of multi-level security in the proposed scheme is that if an imposter or attacker tries to get patient identity from the medical image, he or she requires multiple information in terms of extraction steps and keys, etc. The other reason for proposed this scheme that it improves the payload capacity of many existing watermarking schemes. Experimental results of the scheme indicated that the proposed scheme provides high imperceptibility and more robustness against various types of attacks. Further, the performance of the proposed scheme is found better than existing medical watermarking schemes. Furthermore, quality checking of watermarked medical image is done by various quality measures which are indicated that the quality of the image has fulfilled the benefits of secure telemedicine applications.