Methods to hide quantum information

The revolution of the digital information determined deep changes in society and in our lives. The many advantages of the digital information generated as well new challenges and opportunities in the field of innovation. New devices have appeared beside the powerful software, like printers, scanners, digital cameras, MP3 players, etc. for the creation, handling and utilization of multimedia data. The Internet and the wireless network offered channels for exchanging information. The security, and the correct use of multimedia data, as well as the delivery of the multimedia content to different users constitute another very important subject. The solution to these problems does not contribute only to our better understanding of the speed with which technology develops, but also offers new exploration opportunities. All that follows addresses to the subject concerning hiding the data in multimedia files, and applications in multimedia and communication security. Taking into account the easiness with which digital data is edited or reproduced, the protection and the prevention of the unauthorized use of the multimedia data (audio, image, video, documents) become extremely important. One of the most frequently used electronic formats in which information can be found nowadays is the digital image.