Research And Implementation Of A Fast Encryption Algorithm For MPEG-2 Video

With the development of the digital network, digital multimedia application has become popular deeply and commonly. The security of the High-resolution television program and service on-play becomes more and more important because of such application with different security level—video on-demand, TV program on–pay, television meeting. The encryption for multimedia video can be used widely—not only in the conditional access receiving system of set-top box, digital right management and so on. The biggest difference between general computer application and multimedia application is the large size of video and the real-time requirement in much network application. Most current modern encryption algorithms, which only transform a plaintext message that is the simplest form of multimedia data into unintelligible cipher text, are not appropriate for higher forms such video with very large file sizes. New encryption algorithm is on demand.The key to develop an algorithm to reach the real-time requirement and security quality is to make a good balance between security and the excessive cost of the encryption arithmetic operation. The security quality and the operation time of the algorithm will fall if we reduce the complexity of the encryption; conversely, the security quality and the operation time will increase with the decrease of the complexity of the algorithm. Selective encryption of MPEG video streams has been proposed to reduce encryption requirements, saving in complexity and facilitating new system functionality. In this paper, a two-way selective encryption algorithm (TWVEA) for MPEG video is proposed to compromise the security and speed in the process of encryption. TWVEA adopt key video data to encrypt during the encoding progress to reduce the excessive operation spending; utilize cryptogrammic method with high intensity to protect video and make use of ECC to protect the key in the transmission to receive high security quality.Well, a simple encryption system based on TWVEA with mixed- cryptography is tested. The video encrypted is inapprehensible and the seep of TWVEA is faster than algorithm, a little slower than RVEA algorithm while more secure than RVEA. The performance can be improved in future.