Watermarking with wavelets: Simplicity leads to robustness

Abstract

With ubiquitous computing comes the access of copyrighted work across computing platforms. One may have the same image (or video) on an iPod, as well as a laptop and desktop computer. Safeguarding creative content and intellectual property in a digital form has become increasingly difficult as technologies, such as the Internet, broadband availability and mobile access, advance. It has grown to be progressively easier to copy, modify and redistribute digital media, resulting in great declines in business profits. Digital watermarking is a steganographic technique that has been proposed as a possible solution to this problem. This paper examines a technique for digital watermarking which utilizes properties of the Discrete Wavelet Transform (DWT). The digital watermarking algorithm uses a database of multiple images with various properties. Eight families of wavelets, both orthogonal and biorthogonal, are compared for efficacy. To objectively measure the success of the algorithm and the influence of the mother wavelet, the PSNR for each wavelet family and image is obtained. Noise is introduced to simulate various attacks. Objective measures are used to determine the performance of the algorithm. We find that the simpler wavelet transforms, e.g. the Haar wavelet, outperform the more complex ones.