A novel image encryption algorithm based on two-dimensional general Logostic mapping and output-feedback

A nonlinear coupled two-dimensional generalized Logistic chaotic mapping was proposed by using phase maps and bifurcation graphics, and the complex nonlinear dynamic activities of two-dimensional formula were studied. By using the coupled two-dimensional generalized Logistic chaotic mapping a chaotic sequence was generated, then the chaotic sequence was optimized into secret key stream, and output-feedback technology was introduced in this encryption algorithm, which changes pixels. The results show that the encryption algorithm is extremely sensitive to the key and the encrypted image, the choice of chaotic sequence sensitively depends on the plaintext that enhances the ability of resisting the chosen plaintext attack, and the information entropy of the cipher image is 7.9743, which is very close to the ideal value 8.0000. The encrypted image has random-like distribution behavior of grey values, and the correlation between the encrypted image and the plain image is close to 0. The adjacent pixels have zero co-correlat ion properties, and the encryption method changes the pixel of the original image greatly, which makes the ciphertext resist statistical attack, and the algorithm has the advantages of large space, and the key space reaches 299 bit.