A Robust Digital Image Watermarking Technique Based on DWT and Fastica

With the increasing use of internet and effortless copying, copyright protection for multimedia data has become an important issue. Digital watermarking has emerged as a tool for protecting the multimedia data from copyright infringement. Many literatures have reported about frequency transform based watermarking techniques for data security, since they are robust against image processing attacks. In this paper, an attempt is made to develop a watermarking scheme based on discrete wavelet transform (DWT) and extraction using fast independent component analysis (FastICA) algorithm. A perceptual model is applied with stochastic approach for watermark embedding. This is based on computation of noise visibility function (NVF) which has local image properties where the strength of watermarking is controlled. ICA, an intelligent detection algorithm, which is based on blind source separation technique, is implemented for extraction without the use of previous knowledge of the original image. The features of FastICA are quick convergence, easy to implement and suitable for watermark applications. Robustness of the proposed scheme is validated by implementing common image processing attacks. Peak signal to noise ratio (PSNR) and similarity measure (SM) values are calculated to evaluate the performance of the proposed work.