Chaotic systems are suitable for image encryption owing to their numerous intrinsic characteristics. However, chaotic maps and algorithmic structures employed in many existing chaos-based image encryption algorithms exhibit various shortcomings. To overcome these, in this study, we first construct a two-dimensional logistic tent modular map (2D-LTMM) and then develop a new colour image encryption algorithm (CIEA) using the 2D-LTMM, which is referred to as the LTMM-CIEA. Compared with the existing chaotic maps used for image encryption, the 2D-LTMM has a fairly wide and continuous chaotic range and more uniformly distributed trajectories. The LTMM-CIEA employs cross-plane permutation and non-sequential diffusion to obtain the diffusion and confusion properties. The cross-plane permutation concurrently shuffles the row and column positions of pixels within the three colour planes, and the non-sequential diffusion method processes the pixels in a secret and random order. The main contributions of this study are the construction of the 2D-LTMM to overcome the shortcomings of existing chaotic maps and the development of the LTMM-CIEA to concurrently encrypt the three colour planes of images. Simulation experiments and security evaluations show that the 2D-LTMM outperforms recently developed chaotic maps, and the LTMM-CIEA outperforms several state-of-the-art image encryption algorithms in terms of security.

混沌系统由于其众多的固有特性而适用于图像加密。然而，在许多现有的基于混沌的图像加密算法中采用的混沌图和算法结构表现出各种缺点。为了克服这些问题，在本研究中，我们首先构建了二维逻辑帐篷模块化地图（2D-LTMM），然后使用2D-LTMM开发了一种新的彩色图像加密算法（CIEA），称为LTMM- CIEA。与用于图像加密的现有混沌图相比，二维LTMM具有相当宽且连续的混沌范围和更均匀分布的轨迹。LTMM-CIEA采用跨平面排列和非顺序扩散来获得扩散和混淆特性。跨平面置换同时使三个颜色平面内像素的行和列位置混洗，并且非顺序扩散方法以秘密和随机顺序处理像素。这项研究的主要贡献是构建2D-LTMM以克服现有混沌图的缺点，以及开发LTMM-CIEA以同时加密图像的三个彩色平面。仿真实验和安全性评估表明，在安全性方面，二维LTMM的性能优于最近开发的混沌图，而LTMM-CIEA的性能优于几种最新的图像加密算法。这项研究的主要贡献是构建2D-LTMM以克服现有混沌图的缺点，以及开发LTMM-CIEA以同时加密图像的三个彩色平面。仿真实验和安全性评估表明，在安全性方面，二维LTMM的性能优于最近开发的混沌图，而LTMM-CIEA的性能优于几种最新的图像加密算法。这项研究的主要贡献是构建2D-LTMM以克服现有混沌图的缺点，以及开发LTMM-CIEA以同时加密图像的三个彩色平面。仿真实验和安全性评估表明，在安全性方面，二维LTMM的性能优于最近开发的混沌图，而LTMM-CIEA的性能优于几种最新的图像加密算法。