用模拟退火思想的粒子群算法实现图像分割

采用了一种模拟退火思想的粒子群算法与最大类间方差法相结合的快速阈值分割法对图像进行分割。用粒子群优化算法来搜索阈值向量,每个粒子代表一个可行的阈值向量,通过粒子间的协作来获得最优阈值。为了提高收敛速度,把模拟退火的思想应用在粒子群算法中,最后仿真结论表明,该方法在继承标准粒子群算法原理简单、易于实现、协同搜索等优点的同时,还避免了标准粒子群算法的收敛速度慢问题,有更强的寻优能力,得到理想的结果的同时计算量大大减少。权衡分割精度和计算效率两个方面,文中方法不失为一种实用有效的图像分割算法。     

基于量子粒子群优化算法的最小交叉熵多阈值图像分割*

首先提出了一种减少最小交叉熵适应度函数计算量的快速递推编程技术;然后采用量子粒子群优化法搜索获得图像最优多阈值,并用该阈值实现图像分割。实验分析结果表明,该方法具有实现阈值寻优速度快,最优解对应图像分割效果好的特点。     

基于改进粒子群优化算法的Otsu图像分割方法

Otsu算法分割图像时不依赖于图像的内容,具有较好的适应性,但计算量大和实时性差的缺点限制了其应用。针对这一问题,提出一种基于改进粒子群优化算法的Otsu分割方法。该方法以Otsu算法中的类间方差作为粒子群优化算法的适应度函数,以当前分割阈值作为粒子的当前位置,以阈值更新速度作为粒子的当前速度,以粒子最优适应值的改进量作为惯性权重,在灰度空间动态搜索使类间方差最大的阈值。实验结果表明:该方法能获得与经典Otsu相当的分割效果,而且显著地缩短了分割时间,算法效率更高。     

用模拟退火思想的粒子群算法实现图像分割

采用了一种模拟退火思想的粒子群算法与最大类间方差法相结合的快速阈值分割法对图像进行分割.用粒子群优化算法来搜索阈值向量,每个粒子代表一个可行的阈值向量,通过粒子间的协作来获得最优阈值.为了提高收敛速度,把模拟退火的思想应用在粒子群算法中,最后仿真结论表明,该方法在继承标准粒子群算法原理简单、易于实现、协同搜索等优点的同时,还避免了标准粒子群算法的收敛速度慢问题,有更强的寻优能力,得到理想的结果的同时计算量大大减少.权衡分割精度和计算效率两个方面,文中方法不失为一种实用有效的图像分割算法.     

基于粒子群优化算法和模糊熵的多级阈值图像分割算法

针对现有阈值分割算法利用穷举搜索寻找最优阈值而造成的计算成本较大的问题,提出了一种基于粒子群优化算法和模糊熵的多级阈值图像分割算法。图像分割是图像分析中非常重要的预处理步骤,在提出的方法中,首先选择香农熵和模糊熵作为优化技术的目标函数;然后建立一种基于粒子群优化算法的多层次图像阈值分割,通过最大化香农熵或模糊熵进行图像分割。最后从图像分割数据库中选取Lena、baboon和airplane作为测试图像进行性能分析（包括鲁棒性、效率和收敛性）,并与现有的几种阈值分割算法进行比较。结果显示,提出的算法得到了更高PSNR值和更少的分类误差,证明了该算法是一种高效的多级阈值图像分割算法。     

改进PSO算法在二维最佳阈值图像分割中的应用

针对二维熵图像分割在求取最佳阈值时存在计算量大及粒子群算法容易陷入局部最优、运算速度慢等问题,提出了改进的粒子群优化算法的二维熵图像分割方法。该方法是在雁群启示的粒子群算法基础上,对速度公式进行改进,并引入随机扰动策略,从两个方面同时改进以提高算法的收敛速度,以及克服局部极值的能力。仿真结果表明,将该方法用于阈值寻优减少了搜索时间,提高了收敛速度,强化了图像处理的实时性。     

基于混沌粒子群算法的多阈值图像分割

针对单阈值图像分割方法在求取比较复杂的图像时效果不理想及粒子群算法容易陷入局部最优且速度较慢等等问题,提出了基于混沌粒子群优化算法的多阈值图像分割方法。该方法利用混沌运动随机性、遍历性和初值敏感性,将混沌粒子群优化算法与多阈值法相结合作全局搜索,实验结果表明了基于混沌粒子群优化算法的多阈值图像分割法用于阈值寻优减少了搜索时间,并且运行时间不随阈值数目的增加而显著增加。     

基于粒子群的图像分割

图像分割是图像处理的关键问题之一,为了能够快速有效地选取最优阈值进行图像分割,引入了粒子群算法（PSO）对阈值分割进行优化,提出基于PSO的最大熵图像分割,基于PSO的最大类间方差图像分割以及基于PSO的最小误差图像分割,并进行了分析和研究,可以得出该三种方法可以准确、快速地获取最优阈值进行图像分割。     

基于二进制量子微粒群算法的二维熵图像分割

分析量子计算的特点,对量子旋转门进行研究,给出了新的量子旋转门调整策略,并与离散二进制粒子群优化算法进行组合,提出了二进制量子粒子群优化算法。该算法具有收敛速度快、全局寻优能力强的特点。用典型复杂函数对其进行测试,测试结果表明,算法的优化质量和效率都优于离散二进制粒子群优化算法。将二进制量子粒子群优化算法与阈值法相结合应用于图像分割,结果表明了基于二进制量子粒子群优化算法的二维熵图像分割法用于阈值寻优具有更快的收敛速度和更好的全局寻优能力。     

基于积分图和粒子群优化的肤色分割

为了更快地将肤色区域从图像中分割出来,在二维Ostu方法的基础上,提出了一种将积分图和粒子群优化相结合用于寻找最优分割阈值点的新方法。该方法通过对经过颜色补偿后的图片在YCbCr颜色空间中用二维高斯肤色模型计算肤色概率图,根据二维Ostu算法确定粒子群优化的目标函数,将积分图的方法用于粒子群优化中目标函数的计算,在有效地获取最佳阈值点的同时减少了计算量。实验表明,该方法能有效并且快速地分割出肤色区域。     

自适应最小误差阈值分割算法

对二维最小误差法进行三维推广, 并结合三维直方图重建和降维思想提出了一种鲁 棒的最小误差阈值分割算法. 但该方法为全局算法, 仅适用于分割均匀光照图像. 为 提高其自适应性, 本文采用Water flow模型对非均匀光照图像进行背景估计, 以此获 得原始图像与背景图像的差值图像, 达到降低非均匀光照对图像分割造成干扰的目的. 为进 一步提高分割性能, 本文对差值图像采用γ 矫正进行增强, 然后采用鲁棒最小误差 法进行全局分割, 从而完成目标提取. 最后本文对均匀光照下以及非均匀光照下图像进行了 实验, 并与一维最小误差法、二维最小误差法、三维直方图重建和降维的Otsu阈值分割 算法、灰度波动变换自适应阈值方法以及一种改进的FCM方法在错误分割率和运行时间上进 行了对比. 实验结果表明, 相对于以上方法, 本算法的分割性能均有明显提升.     

高斯尺度空间下估计背景的自适应阈值分割算法

为有效分割非均匀光照图像,提出一种在高斯尺度空间下估计背景的自适应阈值分割算法. 首先,利用二维高斯函数对待处理图像进行卷积操作来构建一个高斯尺度空间,在此空间下进行背景估计,并采用背景差法来消除非均匀光照干扰,从而提取出目标图像;然后,采用 矫正进行增强处理以突出较暗目标信息;最后,经强调谷底的最大类间方差法进行全局分割得到最终结果. 为验证算法的有效性,对非均匀光照条件下文本图像以及非文本图像进行了测试,并与基于偏移场的模糊C均值方法、灰度波动变换自适应阈值分割算法和自适应最小误差阈值分割算法,在错误分割率和运行时间上进行了对比. 实验结果表明,对比以上三种方法,该算法的分割结果更为理想.     

A new social and momentum component adaptive PSO algorithm for image segmentation

In this paper, we present a new variant of Particle Swarm Optimization (PSO) for image segmentation using optimal multi-level thresholding. Some objective functions which are very efficient for bi-level thresholding purpose are not suitable for multi-level thresholding due to the exponential growth of computational complexity. The present paper also proposes an iterative scheme that is practically more suitable for obtaining initial values of candidate multilevel thresholds. This self iterative scheme is proposed to find the suitable number of thresholds that should be used to segment an image. This iterative scheme is based on the well known Otsu’s method, which shows a linear growth of computational complexity. The thresholds resulting from the iterative scheme are taken as initial thresholds and the particles are created randomly around these thresholds, for the proposed PSO variant. The proposed PSO algorithm makes a new contribution in adapting ‘social’ and ‘momentum’ components of the velocity equation for particle move updates. The proposed segmentation method is employed for four benchmark images and the performances obtained outperform results obtained with well known methods, like Gaussian-smoothing method (Lim, Y. K., & Lee, S. U. (1990). On the color image segmentation algorithm based on the thresholding and the fuzzy c-means techniques. Pattern Recognition, 23, 935–952; Tsai, D. M. (1995). A fast thresholding selection procedure for multimodal and unimodal histograms. Pattern Recognition Letters, 16, 653–666), Symmetry-duality method (Yin, P. Y., & Chen, L. H. (1993). New method for multilevel thresholding using the symmetry and duality of the histogram. Journal of Electronics and Imaging, 2, 337–344), GA-based algorithm (Yin, P. -Y. (1999). A fast scheme for optimal thresholding using genetic algorithms. Signal Processing, 72, 85–95) and the basic PSO variant employing linearly decreasing inertia weight factor.     

结合遗传算法的局部最小误差孔穴图像分割法

针对遗传算法和最小误差分割法各自的优缺点,将最小误差分割法与遗传算法进行改进并且相互结合,提出了一种结合遗传算法的局部最小误差孔穴图像分割法。该方法利用局部图像信息确定最佳阈值范围,并根据模拟退火思想对个体适应度进行自适应的调整,从而避免了早熟现象,提高了运算速度。实验结果表明:该方法不但能够准确地分割出孔穴图像,而且运算速度较快,是一种有效的孔穴图像分割方法。     

灰度图像最小误差阈值分割法的二维推广

一维最小误差阈值法假设了目标和背景的灰度分布服从混合正态分布. 考虑到噪声等因素对图像质量的影响, 本文在二维灰度直方图上, 基于二维混合正态分布假设, 给出一维最小误差阈值法的二维推广表达式. 为了提高算法的运行速度, 也给出了快速递推算法. 实验表明, 二维最小误差阈值法是一个有效的图像分割算法, 能够更好地适应目标和背景方差相差较大的图像及噪声图像的分割问题.     

An improved scheme for minimum cross entropy threshold selection based on genetic algorithm

Image segmentation is one of the most critical tasks in image analysis. Thresholding is definitely one of the most popular segmentation approaches. Among thresholding methods, minimum cross entropy thresholding (MCET) has been widely adopted for its simplicity and the measurement accuracy of the threshold. Although MCET is efficient in the case of bilevel thresholding, it encounters expensive computation when involving multilevel thresholding for exhaustive search on multiple thresholds. In this paper, an improved scheme based on genetic algorithm is presented for fastening threshold selection in multilevel MCET. This scheme uses a recursive programming technique to reduce computational complexity of objective function in multilevel MCET. Then, a genetic algorithm is proposed to search several near-optimal multilevel thresholds. Empirically, the multiple thresholds obtained by our scheme are very close to the optimal ones via exhaustive search. The proposed method was evaluated on various types of images, and the experimental results show the efficiency and the feasibility of the proposed method on the real images.     

Multilevel minimum cross entropy threshold selection based on the firefly algorithm

The minimum cross entropy thresholding (MCET) has been widely applied in image thresholding. The search mechanism of firefly algorithm inspired by the social behavior of the swarms of firefly and the phenomenon of bioluminescent communication, is used to search for multilevel thresholds for image segmentation in this paper. This new multilevel thresholding algorithm is called the firefly-based minimum cross entropy thresholding (FF-based MCET) algorithm. Four different methods that are the exhaustive search, the particle swarm optimization (PSO), the quantum particle swarm optimization (QPSO) and honey bee mating optimization (HBMO) methods are implemented for comparison with the results of the proposed method. The experimental results show that the proposed FF-based MCET algorithm can efficiently search for multiple thresholds which are very close to the optimal ones examined by the exhaustive search method when the number of thresholds is less than 5. The need of computation time of using the FF-based MCET algorithm is the least, meanwhile, the results using the FF-based MCET algorithm is superior to the ones of PSO-based and QPSO-based MCET algorithms but is not significantly different to the HBMO-based MCET algorithm.     

采用高斯拟合的全局阈值算法阈值优化框架

采用最大类间方差法、最大熵法和最小误差法3种经典全局阈值方法获得的阈值,存在一定偏差.针对该问题,提出了一种采用高斯拟合的全局阈值算法阈值优化框架(TOF).本优化框架先利用全局阈值算法获得初始阈值,将图像粗分为背景和目标2个部分,然后分别计算各部分均值和方差来拟合出2个高斯分布.由于最佳阈值位于2个高斯分布的交点位置,为此本框架采用多次迭代方式来优化阈值,直至最终收敛到最佳阈值.为提高抗噪性能,结合三维直方图重建和降维思想,提出了一种鲁棒的采用高斯拟合的全局阈值算法阈值优化框架(RTOF).实验结果表明,对于以上经典全局算法,采用本优化方法均能收敛到一个最佳阈值,同时本算法还具有鲁棒的抗噪性能和较高的执行效率.     

Multilevel thresholding selection based on the artificial bee colony algorithm for image segmentation

Multilevel thresholding is an important technique for image processing and pattern recognition. The maximum entropy thresholding (MET) has been widely applied in the literature. In this paper, a new multilevel MET algorithm based on the technology of the artificial bee colony (ABC) algorithm is proposed: the maximum entropy based artificial bee colony thresholding (MEABCT) method. Four different methods are compared to this proposed method: the particle swarm optimization (PSO), the hybrid cooperative-comprehensive learning based PSO algorithm (HCOCLPSO), the Fast Otsu’s method and the honey bee mating optimization (HBMO). The experimental results demonstrate that the proposed MEABCT algorithm can search for multiple thresholds which are very close to the optimal ones examined by the exhaustive search method. Compared to the other four thresholding methods, the segmentation results of using the MEABCT algorithm is the most, however, the computation time by using the MEABCT algorithm is shorter than that of the other four methods.     

Multilevel thresholding using grey wolf optimizer for image segmentation

Multilevel thresholding is one of the most important areas in the field of image segmentation. However, the computational complexity of multilevel thresholding increases exponentially with the increasing number of thresholds. To overcome this drawback, a new approach of multilevel thresholding based on Grey Wolf Optimizer (GWO) is proposed in this paper. GWO is inspired from the social and hunting behaviour of the grey wolves. This metaheuristic algorithm is applied to multilevel thresholding problem using Kapur's entropy and Otsu's between class variance functions. The proposed method is tested on a set of standard test images. The performances of the proposed method are then compared with improved versions of PSO (Particle Swarm Optimization) and BFO (Bacterial Foraging Optimization) based multilevel thresholding methods. The quality of the segmented images is computed using Mean Structural SIMilarity (MSSIM) index. Experimental results suggest that the proposed method is more stable and yields solutions of higher quality than PSO and BFO based methods. Moreover, the proposed method is found to be faster than BFO but slower than the PSO based method.