CMBS: Chaotic Mapping and Bit Level Shift Based Image Encryption

Many scholars have proposed various encryption algorithms to address the correlation and consistency between image pixels, particularly when the entire image exhibits uniformity. However, these algorithms suffer from the problems of not being able to fully realise encryption and being vulnerable to plaintext attacks. Aiming at the problems of how to reduce the consistency and strong correlation among pixels and enhance the security of encrypted image data, this bit-level image encryption algorithm utilizes chaotic mapping. The structure of the algorithm is two disruptions and two diffusions: firstly, the image is disrupted by Arnold chaotic mapping; secondly, the image is processed in chunks, and if there is still strong correlation or consistency between the pixels in the chunks, the pixels of the original image are diffused by combining the coordinate information and logistic chaos. For pixel blocks that have already been processed or do not have strong correlation or consistency, image pixel disambiguation and diffusion are accomplished simultaneously by logistic chaotic mapping and bit-level positional permutation. Finally, S-boxes are introduced to further diffuse the image. By verifying the experimental results, the method in this paper is highly secure and resistant to common attacks.