Multiple-image encryption based on Toeplitz matrix ghost imaging and elliptic curve cryptography

To improve the security of encryption systems, we propose a multiple-image encryption method via Toeplitz matrix ghost imaging and elliptic curve cryptography. Specifically, each unencrypted image is firstly compressed using wavelet transformation. Compressed images are merged into a single image via spatial multiplexing technology. Then, based on the ghost imaging, the phase mask matrix of the speckle sequence is modulated into a random Toeplitz matrix, through the logistic mapping sequence to achieve the encryption of the combined image. The detection data of all images is obtained through a bucket detector. Finally, the obtained detection data is encrypted twice using an elliptic curve asymmetric cryptographic algorithm to obtain the final ciphertext. In the decryption process, images are recovered using elliptic curve, compressive sensing technology and inverse wavelet transformation. This method provides strong security features for encryption systems. The basic principle of the encryption scheme is analyzed theoretically, and the security and robustness of the proposed method are verified by numerical simulation. (letter)