Watermark insertion and detection using contourlet and wavelet transforms

Abstract: Digital watermarking is now an established & cost effective method for data authentication and for protection of multimedia data. Many standard and commercially available software are available for this purpose. In this paper an attempt has been made to modify the method of Reddy and Chatterji [13, 14] by using contourlet transform for the watermark signal. The theoretical background of the method along with the simple development of the contourlet transform has been given. The algorithms for watermark insertion and detection are provided. The method was used for many different types of images and watermarks. A set of five such results are given along with the PSNR (peak signal to noise ratio) values of watermarked images and the detected watermarks.

Keywords: Contourlet transform HVS characteristics, Laplacian pyramid decomposition, directional filter bank, covariance of watermark coefficients.