共查询到18条相似文献,搜索用时 62 毫秒
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基于优化水平集方法的CT图像肺结节检测算法 总被引:1,自引:0,他引:1
对Chan-Vese水平集图像分割方法进行分析和改进,提出了结合全局区域均值和局部边界信息的水平集改进算法,应用于肺部CT图像分割和肺结节检测。在图像分割的目标函数中,在Chan-Vese方法基础上,引入局部边界统计特性能量项,以利于提高肺部医学图像分割的准确率和分割速度。实验表明,该方法可以很好地分割出肺实质轮廓和肺结节病灶区域,在分割速度上比Chan-Vese方法有了明显的提高,检测结果不依赖于初始设置,将人工交互降至最低,有利于实现CT图像肺结节自动检测。 相似文献
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一种基于Canny算子的level-set肺部血管分割算法 总被引:1,自引:0,他引:1
提出一种应用基于CANNY算子的level-set分割方法,三维分割肺部血管.首先根据肺部解剖结构确定肺部血管不同部位的阚值范围进行对血管初始分割,然后再应用高斯过滤异布扩散对初始血管分割的结果进行平滑去噪和CANNY算子检测出初始图像真正的边缘,最后应用level-set细分初始血管分割的结果,解决由于边界模糊产生肺部血管分割不准确的问题.并提出并描述基于Level-set肺部血管树枝杈点的判定方案. 相似文献
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针对Berkels提出的无约束严格凸的图像分割模型,在Bermudez-Moreno对偶算法的基础上提出了一种不仅易于实现并能快速得到全局极小值的梯度投影算法.首先,解释了Bermudez-Moreno对偶算法可用于模型问题的求解并推导出迭代计算格式;然后,证明了迭代格式的收敛性并分析了其收敛速度;最后,仿其实验表明了所提出算法能够有效地、快速地求解图像分割问题. 相似文献
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基于分形理论和神经网络的红外图像分割算法 总被引:2,自引:0,他引:2
针对实现红外图像的分割,快速准确地检测出红外序列中的人造目标的需要,结合分形特征和Ko-honen神经网络的特点,提出了一种基于分形技术的图像分割算法。该算法利用自然背景和人造目标的不同分形特征检测目标,提出了包括分形维数在内的7个红外图像特征,结合神经网络的自组织学习能力来进行图像分割。给出了算法实现的具体步骤。仿真试验结果表明,该算法能有效地实现红外图像的分割。 相似文献
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基于Snake模型的低对比度噪声心脏MRI图像分割 总被引:4,自引:0,他引:4
提出了一种基于Snake模型的低对比度、噪声心脏MRI图像分割算法。Snake模型通过轮廓线的变形得到感兴趣区域(ROI)的边界,但其分割结果依赖于初始轮廓线的位置,且变形曲线容易收敛于局部梯度极大值区域或从弱边界处泄漏,对于深度凹陷的区域也难以分割。通过增加局部面积能量项,扩大了Snake模型寻找边界的范围;在模糊C均值集群分类的基础上,构造模糊能量项,能够较好地处理心脏MRI图像中的弱边界、局部梯度极大值区域、伪影等现象。分割实验证明了改进的模型能够有效地分割低对比度、噪声心脏MRI图像。 相似文献
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介绍了S-粗集的概念, 结合其动态迁移特性给出了可以适应复杂背景和含噪环境的图像S-粗集表示模型, 使静态目标可以将"不好"特性像素点迁移出去. 利用粗糙熵平衡目标和背景粗糙度对边界的影响, 提出一种更具适应性的 图像阈值分割算法. 为了适应离散点的迁移, 同时避免粒度大小的选择, 结合包含度概念给出了图像变精度S-粗集表示模型, 利用精度参数来 控制调节获取最佳分割阈值, 实现目标提取. 仿真实验表明, 所提出算法具有更好的图像分割效果. 相似文献
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Although cardiac magnetic resonance imaging (MRI) can provide high spatial resolution image, the area gray level inhomogenization, weak boundary and artifact often can be found in MR images. So, the MR images segmentation using the gradient-based methods is poor in quality and efficiency. An algorithm, based on the competitive hopfield neural network (CHNN) and the curve propagation, is proposed for cardiac MR images segmentation in this paper. The algorithm is composed of two phases. In first phase, a CHNN is used to classify the image objects, and to make gray level homogenization and to recognize weak boundaries in objects. In second phase, based on the classified results, the level set velocity function is created and the object boundaries are extracted with the curve propagation algorithm of the narrow band-based level set. The test results are promising and encouraging. 相似文献
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基于最大模糊熵原理的多阈值图像分割新算法 总被引:11,自引:2,他引:11
吴薇 《系统工程与电子技术》2005,27(2):357-360
基于最大模糊熵准则,提出了一种新的多阈值图像分割算法。该算法通过定义一种简单的线性模糊隶属度函数,将图像模糊划分为若干个不同的区域;同时采用自适应遗传算法搜索最大模糊熵准则下图像的一组最佳分割阈值,并对遗传算法中的编码方式及交叉算子、变异算子进行了一些有益的改进,极大地减少了计算量和存储空间,加快了算法的搜索速度。通过仿真实验证明该算法对复杂图像良好的分割效果和较强的实时处理能力。 相似文献
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Fast interactive segmentation algorithm of image sequences based on relative fuzzy connectedness 总被引:1,自引:0,他引:1
Tian Chunna & Gao XinboSchool of Electronic Engineering Xidian Univ. Xi''''an P. R. China 《系统工程与电子技术(英文版)》2005,16(4)
1.INTRODUCTION Imagesegmentationistoseparatetheobjectofinter estfrombackground.Itistheimportantfoundation ofhigher levelimageanalysis,anditremainsanopen problem.Sofar,variousalgorithmshavebeenpro posed.However,mostofthealgorithmscanonly dealwithspecifickindsofimages.Theseavailableal gorithmscanbeclassifiedintothreegroupsaccording tothesegmentationstyle,automaticsegmentation,manualsegmentation,andinteractivesegmenta tion[1~5].Theautomaticsegmentationmethods,suchas algorithmsbasedonthegra… 相似文献
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针对传统多阈值图像分割方法中存在的分割精度低、计算量大、分割速度慢等问题,提出了一种基于改进麻雀搜索算法(improved sparrow search algorithm,ISSA)的多阈值图像分割方法.首先,结合鸟群算法(bird swarm algorithm,BSA)中飞行行为的思想优化麻雀搜索算法(sparr... 相似文献
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Tang Yinggan Liu Dong & Guan Xinping Inst. of Electrical Engineering Yanshan Univ. Qinhuangdao P. R. China 《系统工程与电子技术(英文版)》2006,17(4):870-874
1. INTRODUCTION Image segmentation, which groups an image’s pixels into some homogeneous regions with respect to one or more characteristics such as gray-level, color and texture, is a basic and challenging problem in image processing. Many researchers have devoted their efforts to this problem and many segmentation algorithms have been proposed[1], histogram based thresholding algorithm, edge detection method and region growing and merging method for instance. Gaussian mixture model bas… 相似文献
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The active contour model based on local image fitting (LIF) energy is an effective method to deal with intensity inhomo- geneities, but it always conflicts with the local minimum problem because LIF has a nonconvex energy function form. At the same time, the parameters of LIF are hard to be chosen for better per- formance. A global minimization of the adaptive LIF energy model is proposed. The regularized length term which constrains the zero level set is introduced to improve the accuracy of the bound- aries, and a global minimization of the active contour model is presented, in addition, based on the statistical information of the intensity histogram, the standard deviation σ with respect to the truncated Gaussian window is automatically computed according to images. Consequently, the proposed method improves the performance and adaptivity to deal with the intensity inhomo- geneities. Experimental results for synthetic and real images show desirable performance and efficiency of the proposed method. 相似文献
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In imaging on moving target,it is easy to get spacevariant blurred image.In order to recover the image and gain recognizable target,an approach to recover the space-variant blurred image is presented based on image segmentation.Because of motion blur's convolution process,the pixels of observed image's target and background will be displaced and piled up to produce two superposition regions.As a result,the neighboring pixels in the superposition regions will have similar grey level change.According to the pixel's motion-blur character,the target's blurred edge of superposition region could be detected.Canny operator can be recurred to detect the target edge which parallels the motion blur direction.Then in the segmentation process,the whole target image which has the character of integral convolution between motion blur and real target image can be obtained.At last,the target image is restored by deconvolution algorithms with adding zeros.The restoration result indicates that the approach can effectively solve the kind of problem of space-variant motion blurred image restoration. 相似文献