Swift and Precise Reversible Watermarking Scheme for Medical Image Authentication

The proposed method of reversible watermarking is focused upon improving the computational time of traditional watermarking schemes while making no compromises on the exactitude of the original information restored after extracting the watermark data. The method operates by conglomerating the schemes of extracting Hash Message Authentication Code called HMAC using MD5 and wavelet transformation. The loss less aspect of this reversible watermarking is achieved by generating a sequence of bits representing whether any modification has happened on the region exactly where the watermarked data is entrenched. This stream of bits is in turn termed as a private key, very specific to the host image and the watermark data. With this method the need for preserving the original image for the purpose of authentication become totally needless. The Hash Message Authentication Code (HMAC) obtained using MD5 is a reliable code of 128 bits. The chances of generating a similar HMAC is negligibly slim as it is established and the synergy of wavelet transformation for embedding the watermark data reinforces the dependability of this algorithm.