Shaimaa A. El-said, Khalid F. A. Hussein, & Mohamed M. Fouad International Journal of Computer Science and Security, (IJCSS), Volume (4): Issue (5) 366 SECURING IMAGE TRANSMISSION USING IN-COMPRESSION ENCRYPTION TECHNIQUE Shaimaa A. El-said e-mail: Eng.sahmed@windowslive.com Faculty of Engineering / Electronics and Communication Department Zagazig University Zagazig,44519, Egypt . Khalid F. A. Hussein e-mail: khalid_elgabaly@yahoo.com Electronics research institute / Microwaves Department Researches National Institute Dokki, Egypt Mohamed M. Fouad e-mail: fouadzu@hotmail.com Faculty of Engineering / Electronics and Communication Department Zagazig University Zagazig,44519, Egypt . Abstract Multimedia is one of the most popular data shared in the Web, and the protection of it via encryption techniques is of vast interest. In this paper, a secure and computationally feasible Algorithm called Optimized Multiple Huffman Tables (OMHT) technique is proposed. OMHT depends on using statistical-model-based compression method to generate different tables from the same data type of images or videos to be encrypted leading to increase compression efficiency and security of the used tables. A systematic study on how to strategically integrate different atomic operations to build a multimedia encryption system is presented. The resulting system can provide superior performance over other techniques by both its generic encryption and its simple adaptation to multimedia in terms of a joint consideration of security, and bitrate overhead. The effectiveness and robustness of this scheme is verified by measuring its security strength and comparing its computational cost against other techniques. The proposed technique guarantees security, and fastness without noticeable increase in encoded image size. Keywords: Image encryption and compression, optimized multiple Huffman tables, OMHT performance analysis, computational cost analysis 1. INTRODUCTION With the rapid development of multimedia and network technologies, the security of multimedia becomes more and more important, since multimedia data are transmitted over open networks more and more frequently. Typically, reliable security is necessary to content protection of digital images and videos. Encryption schemes for multimedia data need to be specifically designed to protect multimedia content and fulfill the security requirements for a particular multimedia application. For example, real-time encryption of an entire video stream using classical ciphers requires heavy computation due to the large amounts of data involved, but many multimedia