Optimizing color image security using hybrid cryptographic techniques based on sine and logistic maps.

This paper proposes an innovative method to enhance the security of color images by integrating hybrid cryptographic techniques, specifically using Sine maps and a double application of the logistic map. The proposed method encrypts a color image in several distinct phases. In the first phase, the image is converted into an M×N matrix. In addition, the Sine maps generate sequences for each color channel: red, green, and blue. A bit-by-bit XOR operation is applied between the matrix and the sequences, producing the first encrypted image. In the second phase, the logistic map is applied to the output from the first phase, following the same sequence-generation procedure until the encrypted image is obtained. The final phase involves reapplying the Logistic map to the image from phase two using modified Logistic map parameters. A comparison with established techniques demonstrates the effectiveness of the proposed strategy in terms of both security and computational efficiency. Experimental results confirm strong performance, with an average correlation coefficient of −0.00014, NPCR = 99.61%, UACI = 33.61%, entropy = 7.9992, and PSNR = 8.60 dB. The average encryption time is 0.445 s for a 512 × 512 color image, demonstrating high robustness and resistance to various attacks, thereby offering valuable insights for practical integration into image-security frameworks.