Multiple-Image Encryption Based on Compressive Ghost Imaging and Coordinate Sampling

A multiple-image encryption method that is based on a modified logistic map algorithm, compressive ghost imaging, and coordinate sampling is proposed. In the encryption process, random phase-only masks are first generated with the modified logistic map algorithm; multiple secret images are transformed to be sparsed by the 2-D discrete cosine transformation (DCT) operation and scrambled by different random sequences; the scrambled images are then grouped to one combined image with the help of the coordinate sampling matrices; finally, putting the combined image in the object plane of the compressive ghost imaging system, the ciphertext will be obtained from the buck detector and transferred to the receivers. During the decryption, which is the possession of the correct principle keys and the assistant geometrical parameter key, the original secret images can be successfully decrypted by the logistic map algorithm, measurement matrix generations, compressive sensing reconstruction, DCT distribution extraction, inverse DCT transform, and filtering operation.