Designing an arithmetic code for multimedia files compression and encryption

The requirements for encrypting multimedia files are very different than general purpose symmetric encryptions. With constraints including low computation power, minimum data size, and resilient to chosen ciphertext attacks, neither common block ciphers like DES/AES nor other stream ciphers are applicable to protect multimedia files. Recently, many works have been proposed to compress and encrypt these files simultaneously. However, most of them are found with severe security deficits. In this paper, we present a novel and efficient scheme to jointly compress and encrypt multimedia files base on arithmetic code. Compare to other proposed schemes, only our scheme introduces the diffusion property, which further enhances the security of the code. At the end of the paper, varies properties of the scheme are also discussed to prove that the scheme is suitable for compressing and encrypting multimedia files.