A visually meaningful image encryption algorithm based on adaptive 2D compressive sensing and chaotic system

A novel visually meaningful image encryption algorithm is proposed based on adaptive 2D compressive sensing and chaotic system. The plain image is first compressed and encrypted simultaneously by adaptive 2D compressive sensing to obtain the pre-encrypted compressed image. In this process, 3D cat map is used to generate the measurement matrix and the scrambling sequence. Then, the pre-encrypted compressed image is embedded into the host image by dynamic LSB method based on 2(K) correction so as to get cipher images with higher visual quality. A four-dimensional discrete chaotic system is used for region scrambling in the embedding process in order to further improve the security of the algorithm. In the simulation tests, the plain image with the maximum size 2048 x 2048 can be compressed and embedded into a host image of size 512 x 512. The embedding ratio is better than the existing algorithms. Most importantly, our algorithm is tens or even hundreds of times more efficient than other algorithms.