A new chaotic encrypted image based on the trigonometric circle

ABSTRACT

In this paper, we propose a new idea to encrypt images using the piecewise linear chaotic map (PWLCM). We converted the plaintext image abstractly and geometrically in the form of a cylinder so as to form a series of superimposed circles see Figure 2. This imagination allows us to process and encrypt the image using trigonometric operations in a different way. PWLCM used as a pseudo-random generator to perturb the angles generated by our transformation. Our algorithm has high sensitivity in plaintext image and the secret key. Moreover, the results show that the characteristics of our approach have excellent performance, with high scores (NPCR = 99.614%, UACI = 33.422%, entropy (Ciphertext Image) ≈ 8, PSNR = 8,4008 and Correlation Coefficient ≈ 0). The experimental results of the security analysis confirm a high level of security of the proposed cipher text.