ABSTRACT

Digital Watermarking is a technology that embeds information or copyright notices or other verification messages, in machine-readable form, within the content of a digital media file. Watermarks can either be visible or invisible. This technique is better than Digital Signatures and other methods because it does not increase overhead. Digital Watermarking describes methods and technologies that hide information, for example numbers or text, in digital media, such as images, video or audio. The embedding takes place by manipulating the content of the digital data.A digital watermark is a signal permanently embedded into digital data that can be detected or extracted later by means of computing operations in order to make assertions about the data. The watermark is hidden in the host data in such a way that it is inseparable from the data and so that it is resistant to many operations not degrading the host document. Thus by means of watermarking, the work is still accessible but permanently marked. In this new image watermarking scheme the embedding process is done by using Bit replacement technology, which stores multiple copies of the same data that is to be hidden in scrambled form in the cover image. Then, in the recovery process of watermarked image we use Common sense method to recover the closest information from the damaged copies of the data under attack.

Keywords: - Cover image, secrete logo, Haar filter, DWT