Analysis of Wavelet and Contourlet Transform Based Image Watermarking Techniques

Image watermarking is being used for proving the authenticity of image as well as video documents. Several web applications based on the extracted watermark are catching up fast for retrieval of information from web. These applications need a lightweight and robust watermarking method for inserting and extracting watermark from image. In this paper we propose a new image watermarking method based on contourlet transform and compared its performance with a wavelet transform based method. In this technique a watermark bit is embedded into one of the Eigenvalues of a fixed size block of the sub band coefficients obtained using contourlet transform. Watermark extraction process follows the inverse operations used in watermark embedding. The simulation results show that contourlet based method is more robust than wavelet based method even under several attacks but wavelet method gives better PSNR than contourlet based method.