In this period of internet, multimedia data security is crucial issue because there are many cases of illegal production and redistribution through the Internet. Data hiding and encryption algorithms can be used for security and protection of multimedia data. Video encryption is new area of research for researchers. Data hiding in encrypted videos is important to conquer the aim of content annotation, copy right protection, access control and/or tapering detection. This paper summarizes the latest research results on video encryption with a special focus on applicability and on the most widely-deployed video format H.264 including advanced video coding.