The threshold-based segmentation method holds a significant position in traditional image segmentation techniques due to its simplicity, high efficiency, and broad applicability. This method categorizes images into two main categories: single-threshold and multi-threshold, based on the number of selected thresholds
[3]. Compared to single-threshold segmentation, multi-threshold segmentation is more suitable for processing color images that are rich in information. However, as the number of thresholds increases, the computational load of traditional enumeration methods escalates rapidly, lengthening the segmentation time and potentially compromising result accuracy. Therefore, improving the efficiency and accuracy of multi-threshold segmentation is an important research direction. In recent years, the development of intelligent optimization algorithms has provided new pathways to address this issue. Researchers have explored integrating swarm intelligence optimization algorithms with traditional multi-threshold segmentation techniques to reduce computational complexity. Lü et al.
[4] improved the position update strategies for explorers and followers in SSA, proposed an improved SSA that integrates bird flocking behavior optimization. The results show that this algorithm significantly enhanced speed, stability, and optimization accuracy in multi-threshold image segmentation. Zhao et al.
[5] combined piecewise linear chaotic mapping and the firefly algorithm (FA) to improve the SSA, enhancing its ability to explore global optimal solutions. This improved algorithm is employed to optimize a backpropagation (BP) neural network model, successfully predicting PM2. 5 concentrations in Xi'an. Jia et al.
[6] applied the emerging grasshopper optimization algorithm (GOA) to image segmentation, demonstrating that this algorithm not only increased computational speed but also improved segmentation quality. Gao et al.
[7] optimized the artificial bee colony (ABC) algorithm by adjusting adaptive parameters to automatically regulate the individuals' search steps. This improvement effectively addresses the high computational load and low efficiency of the original algorithm while boosting segmentation accuracy and convergence speed. Liu et al.
[8] proposed an improved firefly algorithm (IFA) based on adaptive parameter control, addressing the issues of premature convergence and oscillation in traditional algorithms. They applied it to optimize the maximum entropy image segmentation algorithm,enhancing the accuracy and efficiency of image segmentation. Mishra et al.
[9] proposed a multi-threshold image segmentation method based on WOA and social group optimization for brain magnetic resonance imaging (MRI) image segmentation, using Kapur's entropy as the objective function. The study indicated that this method outperformed particle swarm optimization (PSO)
[10] and genetic algorithm (GA)
[11] in robustness, fast convergence, and practical applicability. Experiments also point out that the segmentation method based on Otsu's method has a faster convergence speed compared to the one based on Kapur's entropy. Xue et al.
[12] proposed the SSA, a new swarm intelligence optimization algorithm inspired by the foraging and anti-predation behaviors of sparrows. Compared to methods like PSO and GWO
[13], SSA exhibits superior optimization performance. However, it has a longer runtime and occasionally became trapped in local optima. To address these shortcomings of the SSA, ISSA was proposed in this paper.