Non blind watermarking technique using enhanced one time pad in DWT domain

The unlimited growth in internet and multimedia leads to large usage of images resulting in huge storage and distribution of multimedia contents. With increasing use of digital transmission techniques the potential risks for multimedia content is high which lead to necessity of protection for authenticity and confidentiality. To protect the confidentiality, one time pad is supposed to be the most secure algorithm. This paper proposes a secure algorithm to protect the watermark image over a public network in digital watermarking and is embedded in Discrete Wavelet Transformation (DWT). The unique key same as size of watermark is generated from the cover image. One time pad is applied using generated unique key to encrypt the watermark image. The encrypted image so formed is embedded into cover image in DWT domain. The experimental results show the effectiveness and robustness of the algorithm using PSNR and NC calculations.