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New normalized nonlocal hybrid level set method for image segmentation 被引量:1
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作者 LOU Qiong PENG Jia-lin +1 位作者 KONG De-xing WANG Chun-lin 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2017年第4期407-421,共15页
This article introduces a new normalized nonlocal hybrid level set method for image segmentation.Due to intensity overlapping,blurred edges with complex backgrounds,simple intensity and texture information,such kind o... This article introduces a new normalized nonlocal hybrid level set method for image segmentation.Due to intensity overlapping,blurred edges with complex backgrounds,simple intensity and texture information,such kind of image segmentation is still a challenging task.The proposed method uses both the region and boundary information to achieve accurate segmentation results.The region information can help to identify rough region of interest and prevent the boundary leakage problem.It makes use of normalized nonlocal comparisons between pairs of patches in each region,and a heuristic intensity model is proposed to suppress irrelevant strong edges and constrain the segmentation.The boundary information can help to detect the precise location of the target object,it makes use of the geodesic active contour model to obtain the target boundary.The corresponding variational segmentation problem is implemented by a level set formulation.We use an internal energy term for geometric active contours to penalize the deviation of the level set function from a signed distance function.At last,experimental results on synthetic images and real images are shown in the paper with promising results. 展开更多
关键词 image segmentation level set method nonlocal method intensity information active contours NORMALIZATION
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Segmentation of Bacteria Image Based on Level Set Method 被引量:1
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作者 WANG Hua CHEN Chun-xiao +1 位作者 HU Yong-hong YANG Wen-ge 《Chinese Journal of Biomedical Engineering(English Edition)》 2008年第4期146-152,共7页
In biology ferment engineering,accurate statistics of the quantity of bacteria is one of the most important subjects. In this paper,the quantity of bacteria which was observed traditionally manuauy can be detected aut... In biology ferment engineering,accurate statistics of the quantity of bacteria is one of the most important subjects. In this paper,the quantity of bacteria which was observed traditionally manuauy can be detected automatically. Image acquisition and processing system is designed to accomplish image preprocessing,image segmentation and statistics of the quantity of bacteria. Segmentation of bacteria images is successfully realized by means of a region-based level set method and then the quantity of bacteria is computed precisely,which plays an important role in optimizing the growth conditions of bacteria. 展开更多
关键词 bacteria image segmentation level set method STATISTICS
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MEDICAL IMAGE SEGMENTATION BASED ON A MODIFIED LEVEL SET ALGORITHM
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作者 杨勇 林盘 +1 位作者 郑崇勋 顾建文 《Journal of Pharmaceutical Analysis》 SCIE CAS 2005年第1期29-32,56,共5页
Objective To present a novel modified level set algorithm for medical image segmentation. Methods The algorithm is developed by substituting the speed function of level set algorithm with the region and gradient infor... Objective To present a novel modified level set algorithm for medical image segmentation. Methods The algorithm is developed by substituting the speed function of level set algorithm with the region and gradient information of the image instead of the conventional gradient information. This new algorithm has been tested by a series of different modality medical images. Results We present various examples and also evaluate and compare the performance of our method with the classical level set method on weak boundaries and noisy images. Conclusion Experimental results show the proposed algorithm is effective and robust. 展开更多
关键词 medical image segmentation level set speed function region information
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A CT Image Segmentation Algorithm Based on Level Set Method 被引量:1
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作者 QU Jing-yi SHI Hao-shan 《Chinese Journal of Biomedical Engineering(English Edition)》 2006年第2期47-52,共6页
Level Set methods are robust and efficient numerical tools for resolving curve evolution in image segmentation. This paper proposes a new image segmentation algorithm based on Mumford-Shah module. The method is used t... Level Set methods are robust and efficient numerical tools for resolving curve evolution in image segmentation. This paper proposes a new image segmentation algorithm based on Mumford-Shah module. The method is used to CT images and the experiment results demonstrate its efficiency and veracity. 展开更多
关键词 medical image segmentation level set Mumford-Shah model Curve evolution
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SVM for density estimation and application to medical image segmentation
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作者 ZHANG Zhao ZHANG Su ZHANG Chen-xi CHEN Ya-zhu 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE CAS CSCD 2006年第5期365-372,共8页
A method of medical image segmentation based on support vector machine (SVM) for density estimation is presented. We used this estimator to construct a prior model of the image intensity and curvature profile of the s... A method of medical image segmentation based on support vector machine (SVM) for density estimation is presented. We used this estimator to construct a prior model of the image intensity and curvature profile of the structure from training images. When segmenting a novel image similar to the training images, the technique of narrow level set method is used. The higher dimensional surface evolution metric is defined by the prior model instead of by energy minimization function. This method offers several advantages. First, SVM for density estimation is consistent and its solution is sparse. Second, compared to the traditional level set methods, this method incorporates shape information on the object to be segmented into the segmentation process. Segmentation results are demonstrated on synthetic images, MR images and ultrasonic images. 展开更多
关键词 Support vector machine (SVM) Density estimation medical image segmentation level set method
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The Method of Flotation Froth Image Segmentation Based on Threshold Level Set
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作者 Ji Zhao Huibin Wang +1 位作者 Lina Zhang Conghui Wang 《Advances in Molecular Imaging》 2015年第2期38-48,共11页
A novel flotation froth image segmentation based on threshold level set method is put forward in view of the problem of over-segmentation and under-segmentation which occurs when the existing method segmented the flot... A novel flotation froth image segmentation based on threshold level set method is put forward in view of the problem of over-segmentation and under-segmentation which occurs when the existing method segmented the flotation froth images. Firstly, the proposed method adopts histogram equalization to improve the contrast of the image, and then chooses the upper threshold and lower threshold from grey value of histogram of the image equalization, and complete image segmentation using the level set method. In this paper, the model which integrates edge with region level set model is utilized, and the speed energy term is introduced to segment the target. Experimental results show that the proposed method has better segmentation results and higher segmentation efficiency on the images with under-segmentation and incorrect segmentation, and it is meaningful for ore dressing industrial. 展开更多
关键词 FLOTATION Froth image segmentation Active CONTOUR Model HISTOGRAM EQUALIZATION Speed Function threshold level set
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An Efficient Liver-Segmentation System Based on a Level-Set Method and Consequent Processes 被引量:1
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作者 Walita Narkbuakaew Hiroshi Nagahashi +1 位作者 Kota Aoki Yoshiki Kubota 《Journal of Biomedical Science and Engineering》 2014年第12期994-1004,共11页
This paper presents an efficient liver-segmentation system developed by combining three ideas under the operations of a level-set method and consequent processes. First, an effective initial process creates mask and s... This paper presents an efficient liver-segmentation system developed by combining three ideas under the operations of a level-set method and consequent processes. First, an effective initial process creates mask and seed regions. The mask regions assist in prevention of leakage regions due to an overlap of gray-intensities between liver and another soft-tissue around ribs and verte-brae. The seed regions are allocated inside the liver to measure statistical values of its gray-intensities. Second, we introduce liver-corrective images to represent statistical regions of the liver and preserve edge information. These images help a geodesic active contour (GAC) to move without obstruction from high level of image noises. Lastly, the computation time in a level-set based on reaction-diffusion evolution and the GAC method is reduced by using a concept of multi-resolution. We applied the proposed system to 40 sets of 3D CT-liver data, which were acquired from four patients (10 different sets per patient) by a 4D-CT imaging system. The segmentation results showed 86.38% ± 4.26% (DSC: 91.38% ± 2.99%) of similarities to outlines of manual delineation provided by a radiologist. Meanwhile, the results of liver segmentation only using edge images presented 79.17% ± 5.15% or statistical regions showed 74.04% ± 9.77% of similarities. 展开更多
关键词 LIVER segmentation level-set GEODESIC Active CONTOUR Speed images STATISTICAL thresholds
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Image segmentation based on Mumford-Shah functional 被引量:5
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作者 陈旭锋 管志成 《Journal of Zhejiang University Science》 CSCD 2004年第1期123-128,共6页
In this paper, the authors propose a new model for active contours segmentation in a given image, based on Mumford-Shah functional (Mumford and Shah, 1989). The model is composed of a system of differential and integr... In this paper, the authors propose a new model for active contours segmentation in a given image, based on Mumford-Shah functional (Mumford and Shah, 1989). The model is composed of a system of differential and integral equations. By the experimental results we can keep the advantages of Chan and Vese's model (Chan and Vese, 2001 ) and avoid the regularization for Dirac function. More importantly, in theory we prove that the system has a unique viscosity solution. 展开更多
关键词 image segmentational Mumford Shah functional Viscosity solution level set method
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Fast Image Segmentation Based on a Two-Stage Geometrical Active Contour 被引量:1
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作者 肖昌炎 张素 陈亚珠 《Journal of Shanghai University(English Edition)》 CAS 2005年第1期40-45,共6页
A fast two-stage geometric active contour algorithm for image segmentation is developed. First, the Eikonal equation problem is quickly solved using an improved fast sweeping method, and a criterion of local minimum o... A fast two-stage geometric active contour algorithm for image segmentation is developed. First, the Eikonal equation problem is quickly solved using an improved fast sweeping method, and a criterion of local minimum of area gradient (LMAG) is presented to extract the optimal arrival time. Then, the final time function is passed as an initial state to an area and length minimizing flow model, which adjusts the interface more accurately and prevents it from leaking. For object with complete and salient edge, using the first stage only is able to obtain an ideal result, and this results in a time complexity of O(M), where M is the number of points in each coordinate direction. Both stages are needed for convoluted shapes, but the computation cost can be drastically reduced. Efficiency of the algorithm is verified in segmentation experiments of real images with different feature. 展开更多
关键词 geometric active contours level set method image segmentation stopping criterion.
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Color Cell Image Segmentation Based on Chan-Vese Model for Vector-Valued Images
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作者 Jinping Fan Shiguo Li Chunxiao Zhang 《Journal of Software Engineering and Applications》 2013年第10期554-558,共5页
In this paper, we propose a color cell image segmentation method based on the modified Chan-Vese model for vectorvalued images. In this method, both the cell nuclei and cytoplasm can be served simultaneously from the ... In this paper, we propose a color cell image segmentation method based on the modified Chan-Vese model for vectorvalued images. In this method, both the cell nuclei and cytoplasm can be served simultaneously from the color cervical cell image. Color image could be regarded as vector-valued images because there are three channels, red, green and blue in color image. In the proposed color cell image segmentation method, to segment the cell nuclei and cytoplasm precisely in color cell image, we should use the coarse-fine segmentation which combined the auto dual-threshold method to separate the single cell connection region from the original image, and the modified C-V model for vectorvalued images which use two independent level set functions to separate the cell nuclei and cytoplasm from the cell body. From the result we can see that by using the proposed method we can get the nuclei and cytoplasm region more accurately than traditional model. 展开更多
关键词 CELL image COLOR image segmentation level set method Active CONTOUR Model
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基于Level Set方法的医学图像分割 被引量:48
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作者 朱付平 田捷 +1 位作者 林瑶 葛行飞 《软件学报》 EI CSCD 北大核心 2002年第9期1866-1872,共7页
对图像分割进行了研究,这是医学图像处理中的关键问题之一.提出了一种结合Fast Marching算法和Watershed变换的医学图像分割方法.首先用非线性扩散滤波对原始图像进行平滑,然后利用Watershed算法对图像进行过度分割,最后用改进的Fast Ma... 对图像分割进行了研究,这是医学图像处理中的关键问题之一.提出了一种结合Fast Marching算法和Watershed变换的医学图像分割方法.首先用非线性扩散滤波对原始图像进行平滑,然后利用Watershed算法对图像进行过度分割,最后用改进的Fast Marching方法对图像进行分割.除此之外,根据区域之间的统计特性的相似度重新定义了Fast Marching方法的速度函数.实验结果表明,该方法能够快速、准确地得到医学图像的分割结果. 展开更多
关键词 level set方法 医学图像分割 水平集 图像处理 Watershed变换
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基于Level Set算法的医学图像分割的研究与实现 被引量:3
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作者 党建武 晁颖 +1 位作者 胡铁钧 张芳 《计算机科学》 CSCD 北大核心 2008年第10期236-237,265,共3页
提出了一种改进的结合基于阈值分割特点的Level Set方法。首先用滤波器对原始图像进行平滑,然后根据当前曲线找到区域的统计特性,最后根据区域之间的统计特性的相似度重新定义了Level Set方法的演化停止准则,从而提高了算法的准确性和... 提出了一种改进的结合基于阈值分割特点的Level Set方法。首先用滤波器对原始图像进行平滑,然后根据当前曲线找到区域的统计特性,最后根据区域之间的统计特性的相似度重新定义了Level Set方法的演化停止准则,从而提高了算法的准确性和自动性。实验结果表明,该方法具有较好的分割效果和较高的分割效率。 展开更多
关键词 level set方法 阈值分割 医学图像分割
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基于GPU的快速Level Set图像分割 被引量:8
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作者 吴仲乐 王遵亮 罗立民 《中国图象图形学报(A辑)》 CSCD 北大核心 2004年第6期679-683,共5页
水平集 (level set)图像分割方法是图像分割中的一个重要方法 ,但是该算法的计算量大 ,往往不能达到实时处理的要求。给出了利用新一代的可编程图形处理器 (GPU)实现 level set的加速算法。首先介绍了如何在 GPU上利用片元渲染程序进行... 水平集 (level set)图像分割方法是图像分割中的一个重要方法 ,但是该算法的计算量大 ,往往不能达到实时处理的要求。给出了利用新一代的可编程图形处理器 (GPU)实现 level set的加速算法。首先介绍了如何在 GPU上利用片元渲染程序进行网格化的线性运算和有限差分 PDE计算 ,把 level set方法的离散化算子映射到 GPU上。由于以数据流处理方式的 GPU的存储访问快 ,具有并行运算能力 ,同时 level set算法演化的显示不再需要把数据从 CPU传到 GPU,因此较大地提高了算法速度与交互显示。文中实现并测试了一个与初始化状态独立的二维 level set的算子用于图像分割 ,并对其运算结果和性能进行了比较 ,结果表明该方法具有更快的速度。 展开更多
关键词 图像分割 水平集方法 level set模型 GPU计算实现 可编程渲染器 图形处理器
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基于Level Set方法的Visible Human Being虚拟人图像处理 被引量:3
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作者 张坤 罗立民 +1 位作者 舒华忠 杨芳 《安徽大学学报(自然科学版)》 CAS 北大核心 2005年第4期66-69,共4页
提出了将基于区域的VectorConfidenceConnected的低级分割方法和基于边界的LevelSet高级分割方法相组合的分割方法,使得边界的平滑性得到了保持;既有效地结合了医学专家的医学背景知识,又提高了分割处理的速度,很好的处理了医学图像中... 提出了将基于区域的VectorConfidenceConnected的低级分割方法和基于边界的LevelSet高级分割方法相组合的分割方法,使得边界的平滑性得到了保持;既有效地结合了医学专家的医学背景知识,又提高了分割处理的速度,很好的处理了医学图像中常见的拓扑结构,实验结果表明该方法切实可行。 展开更多
关键词 VECTOR CONFIDENCE Connected方法 level set方法 医学图像 图像分割
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基于变分Level Set方法的图像分割 被引量:3
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作者 王文杰 封建湖 《计算机工程与应用》 CSCD 北大核心 2006年第18期68-70,共3页
文章主要利用levelset函数隐式地追踪图像的边界来实现图像分割。在该文中首先给出了一个变分问题以及相应的Euler-Lagrange方程,并且提出了一种求解该方程的数值算法,使得计算速度有了很大的提高。数值算例表明,该水平集算法具有数值... 文章主要利用levelset函数隐式地追踪图像的边界来实现图像分割。在该文中首先给出了一个变分问题以及相应的Euler-Lagrange方程,并且提出了一种求解该方程的数值算法,使得计算速度有了很大的提高。数值算例表明,该水平集算法具有数值稳定性,不会出现振荡现象,可以很好地处理拓扑结构的变化。 展开更多
关键词 图像处理 level set方法 level set函数 图像分割
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基于level sets的医学图像分割 被引量:4
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作者 吴月娥 周康源 +1 位作者 李传富 张卿 《北京生物医学工程》 2006年第3期240-243,268,共5页
医学图像分割是一个非常重要的研究领域。它主要应用于病人诊断、图像引导手术,以及医学数据可视化。解决这个问题的一个常用方法就是利用活动轮廓或“snake”来分割感兴趣的物体。文中给出两种活动轮廓模型,其中一种基于边缘停止函数,... 医学图像分割是一个非常重要的研究领域。它主要应用于病人诊断、图像引导手术,以及医学数据可视化。解决这个问题的一个常用方法就是利用活动轮廓或“snake”来分割感兴趣的物体。文中给出两种活动轮廓模型,其中一种基于边缘停止函数,而另一种是一个能量最小化算法。两种方法都采用level-sets模型,利用一个Lipschitz函数来进行自动拓扑变化。实验表明第一种方法仅仅只能检测边缘梯度较大的物体,而第二种方法没有这样的限制。 展开更多
关键词 医学图像分割 level-sets模型 活动轮廓
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A distribution prior model for airplane segmentation without exact template 被引量:1
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作者 DAI Ming ZHOU Zhiheng GUO Yongfan 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2020年第1期56-63,共8页
In many practical applications of image segmentation problems,employing prior information can greatly improve segmentation results.This paper continues to study one kind of prior information,called prior distribution.... In many practical applications of image segmentation problems,employing prior information can greatly improve segmentation results.This paper continues to study one kind of prior information,called prior distribution.Within this research,there is no exact template of the object;instead only several samples are given.The proposed method,called the parametric distribution prior model,extends our previous model by adding the training procedure to learn the prior distribution of the objects.Then this paper establishes the energy function of the active contour model(ACM)with consideration of this parametric form of prior distribution.Therefore,during the process of segmenting,the template can update itself while the contour evolves.Experiments are performed on the airplane data set.Experimental results demonstrate the potential of the proposed method that with the information of prior distribution,the segmentation effect and speed can be both improved efficaciously. 展开更多
关键词 image segmentation active contour model(ACM) prior distribution level set method
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基于Level Set方法的低对比度医学图像分割 被引量:5
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作者 陆东莹 庄天戈 《上海交通大学学报》 EI CAS CSCD 北大核心 2006年第8期1444-1447,共4页
基于Level Set方法,提出了一种应用于对低对比度医学图像进行分割的改进的FastMarching方法.该方法结合演化曲线在演化过程中平均能量的变化特性,重新定义Fast Marching算法的停止准则,从而提高了算法的鲁棒性和自动性.实验结果表明,所... 基于Level Set方法,提出了一种应用于对低对比度医学图像进行分割的改进的FastMarching方法.该方法结合演化曲线在演化过程中平均能量的变化特性,重新定义Fast Marching算法的停止准则,从而提高了算法的鲁棒性和自动性.实验结果表明,所提出算法的分割效果良好. 展开更多
关键词 FAST Marching方法 level set方法 医学图像分割 停止准则
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基于Level Set的交互式快速分割算法 被引量:3
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作者 孙海鹏 余伟巍 席平 《工程图学学报》 CSCD 北大核心 2011年第3期45-51,共7页
三维医学图像数据量大,并且受噪声、边界模糊等原因的影响,致使三维分割过程消耗时间较长,容易产生欠分割或过度分割。针对以上问题,提出一种基于Level Set的三维快速分割算法,采用Fast Marching获取二维分割区域,优化轮廓边界,利用直... 三维医学图像数据量大,并且受噪声、边界模糊等原因的影响,致使三维分割过程消耗时间较长,容易产生欠分割或过度分割。针对以上问题,提出一种基于Level Set的三维快速分割算法,采用Fast Marching获取二维分割区域,优化轮廓边界,利用直线数值微分算法(Digital Differential Analyzer,DDA)提取轮廓像素;进一步引入扫描线种子填充思想,实现医学图像的三维快速分割。实验结果表明,上述算法能够快速准确地分割出感兴趣区域。 展开更多
关键词 计算机应用 医学图像三维分割 levelset算法 数值微分算法 扫描线种子填充
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基于形变模型Level Set方法的图像分割 被引量:5
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作者 胡赛荣 周付根 《中国体视学与图像分析》 2003年第1期49-54,共6页
本文阐述了基于形变模型(Deformable Models)的Level Set分割方法的基本原理及其特点,介绍了在图像域的实现方法,实现并改进了基于该模型的Narrow Band快速算法。该算法的基本流程是:先在需要分割的目标内或外给定一封闭的初始曲线,通过... 本文阐述了基于形变模型(Deformable Models)的Level Set分割方法的基本原理及其特点,介绍了在图像域的实现方法,实现并改进了基于该模型的Narrow Band快速算法。该算法的基本流程是:先在需要分割的目标内或外给定一封闭的初始曲线,通过Gaussian滤波后计算图像的梯度,最后通过Narrow Band 算法完成轮廓线的抽取。该算法应用于医学CT/ MRI影像以及显微图像的目标分割中,取得了较好的实验结果,证明该方法非常适合于对具有分支、突触以及拓扑结构变化的目标进行快速精确分割。文中给出了算法实现的基本流程、相关参数的选取准则和部分实验结果。实验发现算法中涉及的参数对提取的轮廓线的精确和光滑程度有较大影响。 展开更多
关键词 形变模型 level set NARROW Band算法 图像分割 医学影像
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