A NOVEL DATA DEPENDENT MULTIMEDIA ENCRYPTION ALGORITHM SECURE AGAINST CHOSEN-PLAINTEXT ATTACKS

摘要

A novel encryption algorithm secure to chosen-plaintext attacks is presented. As opposed to traditional key algorithms, one of the keys in the algorithm presented depends on the message itself. Two encryption matrices are generated by means of singular value decomposition (SVD), using a portion of the message. The two encryption matrices generated are further multiplied into the left and right sides of other data frames for encryption in the transmitter. Without additional information, except for a key and an integer for signs, the encryption matrices can be found and, thus, the original data obtained at the receiver. This is done by exploiting special properties of the SVD of real symmetric matrices. Hence, the algorithm performs time-varying encryption (and, thus, decryption), i.e. the algorithm generates time-varying ciphertexts depending on both the design parameters and the plaintext itself. Since the encryption depends on message data, it leads to a good solution to various known attacks, including chosen-plaintext attacks. The algorithm can be applied to any signal such as text, audio, and image, etc.