Development of Enhanced Algorithm for Information Security Through Watermarking

Abstract

Digital watermarking is a technique for inserting information (watermark) into an image, which can be later extracted or detected for variety of purposes including identification and authentication purpose. With this technique, we can recognize the source, owner, distributor or creator of a document or an image.Digital watermarks are potentially useful in many applications including : ownership assertion, fingerprinting, copy prevention or control. Digital cinema can be considered as a practical application, where information can be embedded as a watermark in every frame. Now, there are few important issues that arise in the study of digital watermarking techniques and they are : capacity, robustness, transparency and security. Until now, there are only few of the techniques through which watermarkingcan be done. The easiest way to watermark an image/video, is to change directly the values of the pixels, in the spatial domain. But there is a drawback of this technique that the inserted information may be easily detected using computer analysis. A more advanced way to do it, is to insert the watermark in the frequency domain, using one of the well known transforms : Discrete Fourier Transform (DFT), Discrete Cosine Transform (DCT), Discrete Wavelet Transform (DWT) . Other techniques are possible as well, like using Fractals.