Enhanced multiple Huffman table (MHT) encryption scheme using key hopping

Efficient multimedia encryption algorithms play a key role in multimedia security protection. One algorithm known as the MHT (multiple Huffman tables) method was recently developed by Wu and Kuo (2001; 2000). Although MHT has many desirable advantages, it is vulnerable under the chosen-plaintext attack (CPA). In this work, an enhanced MHT encryption scheme is proposed to remedy this drawback using the idea of key hopping. It is demonstrated by mathematical analysis that our proposed scheme is secure against chosen plaintext attack.