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Cryptanalysis of an MPEG-Video Encryption Scheme Based on Secret Huffman Tables

Shujun Li·Guanrong Chen·Albert Cheung·Kwok-Tung Lo
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Abstract

This paper studies the security of a recently-proposed MPEG-video encryption scheme based on secret Huffman tables. Our cryptanalysis shows that: 1) the key space of the encryption scheme is not sufficiently large against divide-and-conquer (DAC) attack and known-plaintext attack; 2) it is possible to decrypt a cipher-video with a partially-known key, thus dramatically reducing the complexity of the DAC brute-force attack in some cases; 3) its security against the chosen-plaintext attack is very weak. Some experimental results are included to support the cryptanalytic results with a brief discuss on how to improve this MPEG-video encryption scheme.

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Shujun Li, Guanrong Chen, Albert Cheung, Kwok-Tung Lo. 2007-10-24. Cryptanalysis of an MPEG-Video Encryption Scheme Based on Secret Huffman Tables. https://doi.org/10.1007/978-3-540-92957-4_78

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