Visually secure encryption embedded with multiple types of images using semi-tensor product compressed sensing

An image encryption scheme with visual security is designed by combining the semi-tensor product compressed sensing (STP-CS) with multi-embedding strategy. Specifically, the optimized measurement matrix is firstly generated by chaotic system and singular value decomposition (SVD), and the optimized measurement matrix is used to obtain the measurement value matrix by STP-CS operation on the color image. Next, the reorganized measurement value matrix is scrambled and diffused with the key matrix generated by 2D Logistic-Sine-coupling map (2D-LSCM) to obtain the noise-like encrypted image. Finally, an image embedding method is introduced to embed the compressed noise-like encrypted image into a color or grayscale carrier image to obtain a visually secure color or grayscale encrypted image. SHA-256 is used to generate the initial values of chaotic systems, which are embedded into the carrier image to effectively reduce transmission and storage. The simulation results show that the visually secure encryption scheme is more reliable and outperforms other encryption algorithms.