Encryption Based Medical Image Watermarking against Signal Processing Attacks

The protection of data is of at most importance 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 algorithm proposed in this study is the watermarking technique in the transform domain to ensure secure transfer of medical data. Using DWT transformation and substitution method, we embed the watermark into the cover image and the watermarked image is then encrypted by using the symmetric stream cipher techniques. Performace of the proposed algorithm is analyzed against various signal processing attacks like compression, filtering, noise and histogram equalization and desired outcome is obtained without much degradation in extracted watermark and watermarked image quality.