Image encryption method and decryption method based on Hash chain compressed sensing

TL;DR: In this paper, an image encryption method and decryption method based on Hash chain compressed sensing was proposed, in which a first Hash chain and a second Hash chain are generated according to an initial key; a measurement matrix and an encryption matrix are acquired according to the first hash chain and the second hash chain; compressed measurement is carried out on a sparse representation matrix of a plaintext image through the measurement matrix, thereby acquiring a measurement result matrix; and an encrypted image matrix is acquired according with the measurement result matrices and the encryption matrix.

Abstract: The invention provides an image encryption method and decryption method based on Hash chain compressed sensing. According to the encryption method, a first Hash chain and a second Hash chain are generated according to an initial key; a measurement matrix and an encryption matrix are acquired according to the first Hash chain and the second Hash chain; compressed measurement is carried out on a sparse representation matrix of a plaintext image through the measurement matrix, thereby acquiring a measurement result matrix; and an encrypted image matrix is acquired according to the measurement result matrix and the encryption matrix. Only the initial key needs to be stored in a whole encryption process, so the key storage space and communication consumption are reduced. The key sensitivity ofa Hash function is very high, so completely different Hash sequences are generated due to small changes of an initial key value. The measurement matrix does not need to be stored at a position of a relay node, so the possibility that data is stolen at the position of the relay node is reduced, and the data transmission security is improved. The data security is ensured, and moreover, the key spaceoccupation quantity is reduced.