Image encryption based on a hyperchaotic hyperbolic optoelectronic oscillator and the Tetris game

In this paper, we propose, to our knowledge, a novel image encryption scheme based on a hyperchaotic hyperbolic optoelectronic oscillator and the Tetris game. We first demonstrate that a hyperbolic optoelectronic oscillator is capable of displaying highly complex dynamical behavior such as hyperchaos in almost the entire range of its control parameter. Later on, leveraging on such hyperchaotic behavior, we perform efficient image encryption. In the image encryption process, we use a simultaneous permutation-diffusion by channel operation. Prior to that, a plain image pixel rewriting operation and a new pixel-channel permutation based on the rank orders of the values in the hyperchaotic sequence generated by the optoelectronic oscillator are performed. The major core of the permutation phase is a new scrambling by extraction and recombination technique, which is inspired by the Tetris game. In the entire encryption process, the hyperchaotic key stream used is made dependent on the plain image by the SHA-256 function. Results demonstrate that the proposed technique is more efficient than some existing ones and is secure enough to resist existing attack strategies.