In present years, there has been momentous progress in multimedia technologies. Transmission of multimedia data such as audio, video and pictures above the Internet is now-a-days extremely common. Though internet is extremely insecure channel and this poses a number of protection issues. To accomplish confidentiality and protection of multimedia data above an insecure channel like the Internet, a number of encryption schemes have been proposed. The existence of multimedia technology in this era has promoted digital images to play a more important role than the traditional texts, which demand serious protection of users’ privacy for all applications.