WATERMARK TECHNIQUE FOR AUTHENTICATION OF VISIBLY WATERMARK IMAGES

With the rapid spread of computer networks and the wide use of multimedia technologies, many watermarking techniques are now under development and investigation for protecting owner's intellectual rights. Watermarks can be divided into two types, visible and invisible watermarks, physical visible watermarks have been used for centuries. Now days it is used in digital library, in video broad casting, and other multimedia services. The visible watermark may face several problems. Among these problems, watermark removal and unauthorized insertion are two main concern. This paper proposes a method of invisible watermark to overcome these problems. The watermarking process based on hiding a selected watermark object, that holds a little a mount of information relative to the source object, inside the cover image which has to be authenticated. The processes are based on using invisible watermarks to protect visibly watermarked images which are done by using different techniques. The experiments have shown that the proposed algorithm can provide a very effective protection for watermarked images.