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1.
Extracting geometric data of landmarks from fluoroscopic images plays an important role in camera calibration process of a fluoroscopic-image-based surgical navigation system. Connected components labeling is the essential technique for the extraction. A new fast connected components labeling algorithm was presented. The definition of upward concave set was introduced to explain the algorithm. Feasibility and efficiency of the algorithm were verified with experiments. This algorithm performs well in labeling non-upward concave set connected components and applies to landmarks labeling well. Moreover, the proposed algorithm possesses a desirable characteristic that will facilitate the subsequent processing of fluoroscopic images.  相似文献   

2.
IntroductionDataminingistheprocessofidentifyinguseful,valid,novelandultimatelyunderstandablepat-ternsindata[1],andis“themostd...  相似文献   

3.
A New Algorithm for Mining Frequent Pattern   总被引:3,自引:0,他引:3  
Mining frequent pattern in transaction database,time-series databases,and many other kinds of databases have been studied popularly in data mining research.Most of the previous studies adopt Apriori-like candidate set generation-and-test approach.However,candidate set generation is very costly.Han J.proposed a novel algorithm FP-growth that could generate frequent pattern without candidate set.Based on the analysis of the algorithm FP-growth,this paper proposes a concept of equivalent FP-tree and proposes an improved algorithm,denoted as FP-growth,which is much faster in speed,and easy to realize,FP-growth adopts a modifeid structure of FP-tree and header table,and only generates a header table in each recursive operation and projects the tree to the original FP-tree,The two algorithms get the same frequent pattern set in the same transaction database,but the performance study on computer shows that the speed of the improved algorithm,FP-growth,is at least two times as fast as that of FP-growth.  相似文献   

4.
采用更接近实际的随机值脉冲噪声对混合噪声图像中的脉冲噪声部分进行描述,基于自适应Volterra滤波方法,提出了一种能够有效去除图像混合噪声的LMSV滤波算法.在此基础上,针对LMS算法收敛速度慢,步长因子不易确定的特点,提出了一种改进的自适应Volterra图像滤波算法(NLMSV算法).理论分析和计算机仿真实验表明,相比于传统的图像去噪方法,本文方法在去除图像混合噪声和保留图像边缘细节方面的性能要明显优于其他算法,并且图像受污染率越高,该方法表现出的性能越好.  相似文献   

5.
Imagesegmentationplaysanimportantrolein imageanalysisaswellasinhigh levelimageinter pretationandunderstandingsuchasrobotvision, objectrecognition,andmedicalimaging.Numerous segmentationmethodshavebeendeveloped.How ever,medicalimagesareoftencorruptedbyno…  相似文献   

6.
本文提出一种快速递推滤波算法,用于估计自回归(AR)模型系数。数值试验表明高分辨率的功率谱都是由高阶AR模型构成,高阶范围内有一最佳阶数存在,由于本算法是一种最优滤波算法,对噪声不敏感,小数据量时优于Marple算法,大数据量时优于快速付利叶变换,从文献记载的结果以及我们计算的实例看,有较高的分辨率。从本算法原理还能派生出若干类似算法。  相似文献   

7.
将图像稀疏表示方法引入到交通图像处理中,实现了一种基于K-SVD的正交匹配追踪的交通图像去噪算法.该算法通过奇异值分解,DCT字典进行自适应更新,形成更能表示图像结构的超完备字典.实验结果表明,相对于传统图像增强方法(中值滤波、均值滤波、基于小波滤波)和基于DCT冗余字典的稀疏表示图像增强方法,该算法能更有效地去除交通图像噪声,得到更高的峰值信噪比.  相似文献   

8.
提出一种求精简规则的带支持信息的增量式算法IDMA,该算法改进了传统挖掘算法的缺点,可充分利用已挖掘出的规则集来对新增实例进行决策规则挖掘,同经典Rough集挖掘算法比较,算法IDMA计算过程简单,而且效率较高.  相似文献   

9.
基于小波卡尔曼滤波的加速度计降噪方法   总被引:1,自引:0,他引:1  
针对GF-INS中加速度计降噪的实际问题,提出了一种非零均值观测噪声小波卡尔曼滤波算法.在非标准观测噪声条件下,利用滑动数据窗内的小波变换实时在线估计出观测噪声的方差和均值,作为标准卡尔曼滤波的修正信息,从而实现了标准卡尔曼滤波算法的扩展.实验结果表明,在观测噪声为非标准噪声且统计规律未知的条件下,该自适应降噪方法能获得较好的滤波效果,加速度计信号的噪声方差强度减少了3个数量级.  相似文献   

10.
物流园区功能区块的合理布局对于降低物流成本、提高物流作业效率有重要意义.传统的研究主要建立在假定物流园区是矩形的理想情况下,本文基于栅格数据结构,构建了以运输成本最小为目标的不规则物流园区功能区块布局的集合划分模型,并引入了栅格图像矢量化技术,用于提取布局形成后的图像拓扑结构,获得路网信息,然后设计了基于割树技术的变邻域搜索算法进行求解.最后以某物流园区为例,通过MATLAB编程计算得出布局方案,验证了本文模型和算法的有效性.  相似文献   

11.
针对声发射数据采集过程易受随机噪声干扰,提出了Rao—Blackwellised粒子滤波的信号降噪方法。在地震波模型的基础上,建立了声发射信号的状态空间模型。由于两者在某些方面有相通性,从而把降噪问题转为在状态空间模型下的滤波问题。首先,通过对构造信号的仿真实验,验证Rao—Black—wellised粒子滤波能够用于信号滤波;其次,利用Rao—Blackwellised粒子滤波,对石灰岩声发射信号进行降噪处理,并取得较好的滤波效果,从而为处理声发射数据提供一条新途径。  相似文献   

12.
为改善图像效果,在对现有的椒盐噪声自适应中值滤波算法分析的基础上,提出了基于邻域相关的自适应中值偏移滤波算法。算法对自适应中值滤波算法的处理过程进行改进。当滤波窗口大于设定的最大值时,根据像素点邻域内的像素点灰度值分布在不同的区间,将像素点灰度值的复原分为偏大或偏小两种情况。受污染像素点的滤波输出值为偏移的中值,偏移的距离根据改进的自适应中值滤波算法运行时滤波窗口的大小来决定。从仿真结果可见:该算法滤波后的图像具有较高的峰值信噪比,对图像细节的保留能力和抑制椒盐噪声的能力都有一定的提高。  相似文献   

13.
A new algorithm based on rough core was proposed to extract all relative-attribute reducts in decision information systems of large-scale records. In the algorithm, the rough core of the decision-making information system is first calculated. Then, an approach based on a top-down strategy is adopted to select the non-core condition attributes and generate candidate relative-attribute reducts. Finally, the set of all relative-attribute reducts is obtained by pruning the candidate relative-attribute reducts. Experimental results show that the proposed algorithm is superior to the other methods such as the algorithm without computing core, the exhaustive method and the discernibility matrix method in extracting all relative-attribute reducts for large-scale data sets.  相似文献   

14.
We adapted Russo's image noise filtering technique by introducing an adaptive parameter, noise possibility. This parameter potentially indicates whether a pixel is noise. The improved Russo's method was applied to process the Lena image and a remote sensing image corrupted by noise. The results show that it has a stronger noise filtering ability than other traditional techniques such as Wiener filtering.  相似文献   

15.
交通信息的完整性直接影响着城市交通管理的效率.针对城市道路交通中因路段检测器覆盖不全或设备损坏等造成的流量检测数据缺失问题,本文提出基于生成式对抗网络 (Generative Adversarial Network,GAN)算法的交通流量数据补全方法.首先,以路段实际流量为基础,进行图像化处理生成路网二维信息图;其次,计算考虑时空信息补偿的路网关联矩阵,利用GAN算法分析并实现路网二维信息图缺失部分的补全,进而得到路段交通流量的完整数据;最后,利用实际数据,对比分析了本文方法与相空间重构的卡尔曼滤波方法对缺失数据的补全情况.实例分析结果验证了本文方法的可行性和有效性.  相似文献   

16.
针对噪声符合高斯分布的曲面图像分割问题,提出了一种基于变分水平集方法的隐式曲面上噪声符合高斯分布的图像分割模型。为定义隐式曲面上图像区域划分的动态轮廓线,引入另一个动态水平集函数,其零水平集与隐式曲面的交线即为曲面上区域划分的轮廓线。该模型采用N个水平集函数划分2^N个区域的区域竞争策略。通过变分方法得到图像分割空间轮廓线演化的梯度降方程。通过显式差分格式对演化方程进行离散。实验结果表明,该模型对曲面上噪声符合高斯分布的图像具有良好的分割效果,并且在图像分割的同时能够完全保持曲面固有的几何特征。  相似文献   

17.
IntroductionWith the development of medical imagingtechniques,many devices such as computed tomo-graphy,positron emission tomography,singlephoton emissioin computed tomography,magneticresonance imaging,and ultrasound scanners arewidely available for capturing the planar images ofhuman organs directly in machine- readable form.These medical imaging methods bring a lot of ad-vantages to clinical diagnosis and treatment.How-ever,due to these systems'2 - D imaging modali-ties,it is difficult to un…  相似文献   

18.
Block-matching and 3D-filtering(BM3D) is a state of the art denoising algorithm for image/video,which takes full advantages of the spatial correlation and the temporal correlation of the video. The algorithm performance comes at the price of more similar blocks finding and filtering which bring high computation and memory access. Area, memory bandwidth and computation are the major bottlenecks to design a feasible architecture because of large frame size and search range. In this paper, we introduce a novel structure to increase data reuse rate and reduce the internal static-random-access-memory(SRAM) memory. Our target is to design a phase alternating line(PAL) or real-time processing chip of BM3 D. We propose an application specific integrated circuit(ASIC) architecture of BM3 D for a 720 × 576 BT656 PAL format. The feature of the chip is with 100 MHz system frequency and a 166-MHz 32-bit double data rate(DDR). When noise is σ = 25, we successfully realize real-time denoising and achieve about 10 d B peak signal to noise ratio(PSNR) advance just by one iteration of the BM3 D algorithm.  相似文献   

19.
针对应用卡尔曼滤波器进行车辆GPS导航信号的动态滤波时难以建立精确的数学模型以及传统小波变换在实时性方面存在不足,提出了基于提升小波变换的GPS动态滤波新算法.该算法采用提升小波变换对车辆GPS导航信号进行分解;用3σ准则和多项式插值方法对各层提升小波变换系数进行粗差探测与数据修复;采用模平方软阈值去噪算法对各层提升小波变换系数进行去噪;最后进行提升小波逆变换,从而实现车辆GPS导航信号的动态滤波。仿真实验结果表明,该算法的导航定位精度优于卡尔曼滤波算法;虽然在导航定位精度方面稍比传统小波变换算法的性能高,但比传统小波变换算法速度快一倍;显然该算法对车辆GPS导航系统是有效的.  相似文献   

20.
针对基于视频监控的密集行人群识别难度大,运动轨迹提取困难,运动语义信息挖掘不足 等问题,本文提出基于多目标跟踪FairMOT框架及K-means聚类的行人轨迹捕获和运动语义信 息感知方法。首先,利用多目标跟踪算法提取视频中行人群目标过街时的运动轨迹特征向量;然 后,通过分析轨迹坐标的数值分布特点,设计了一种协方差滤波算法STCCF,以检测和剔除“准静 态轨迹”,得到行人群目标运动轨迹簇;最后,针对已提取的轨迹簇,应用K-means聚类方法,选取 S系数(Silhouette Coefficient)和DB指数(Davies Bouldin Index)两个指标,感知行人聚集和消散点 等场景语义特征。实验分析表明,算法从提取到的2689条轨迹中辨识出179条“准静态轨迹”,检 出率为81.73%;视频场景中的行人目标源点和消失点的解析结果与人工辨识结果吻合,验证了密 集行人群轨迹提取和运动语义信息感知方法的有效性。本文研究可为数据驱动的行为预测和轨 迹建模提供基础。  相似文献   

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