Design Of Video Encryption Scheme And Application In The License Plate Protection System

With the rapid development of multimedia technology, the video technology based on the network has been widely used in many occasions, such as video conference, video chat, video surveillance, digital television and so on. The security problem of video privacy has attracted close attention with people’s increasing consciousness on safety and law. In some video system involved with confidential information in business, politics, military, the vehicle that as a entity closely connected with people also reflects the owner personal information, so the protection of vehicle information is necessary. The speed of the traditional whole frame encryption has already cannot satisfy the real-time demand of the video that base on the network. Therefore, in order to improve the encryption speed and ensure the privacy information of the video, only encrypting some part of the important information of the video (such as license plate area) has become a hotspot of the research.The most popular video coding standard h.264 has been widely applied in the environment that demand high requirement of the image transmission and real-time transmission. For the protection of the license plate information in the video, the main work of this paper is given as follows:(1) A scheme of fast detecting licence plate effective area(the character area of the license plate) based on coding characteristics of the h.264 is proposed. The license plate region and background region(the license plate area) is distinguished by using the color and the geometric characteristics of the license plate as well as the FMO of the h.264.(2) A fast video encryption scheme based on chaotic system is proposed As regard for the shortcomings of the Logistic map, an improved Logistic map is constructed. Then the improved map and Tent map is combined to generate the one-dimensional mixed chaotic sequences, and the mixed chaotic sequences are used to generate the binary key stream flow of the video encryption Finally aiming at the problems of limited space and low security of the encryption in frame prediction model and MVD, an improved frame prediction model encryption and MVD encryption scheme is proposed. Experiments show that this scheme can disrupt the detail information of the video, and it has stronger ability to resist attack, lower computational complexity and smaller compression rate, moreover, the encrypted video also has good format compatibility.(5) For the confideisiarlity lequirernents of the real-time video system, combined with the proposed fast detecting licence plate effective area scheme and improved video encryption scheme, a license plate protection scheme based on h.264 is proposed in this papa; where a chaos-based key distribution plan is designed. Experrments show that the scheme has lower computational complexity, and it also can protect the license plate area safely and fast.