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1.
高光谱图像目标检测的核信号空间正交投影法   总被引:1,自引:0,他引:1  
针对非线性混合下的亚像元目标检测问题, 提出一种基于核函数的信号空间正交投影方法(KSSP)。该方法作为信号空间正交投影方法(SSP)的非线性推广, 首先将原空间中像元矢量经非线性映射转换到高维特征空间,然后在特征空间中用线性信号空间正交投影进行目标检测。通过核技巧, 核信号空间正交投影不必知道具体的非线性映射形式。经模拟数据与真实高光谱图像数据实验证明, KSSP 方法在目标检测性能上优于SSP, 且对噪声的抑制也有很好的效果。  相似文献   

2.
提出了一种基于核函数度量相似性的遥感影像变化检测算法。该算法通过比较两个时相特征向量的概率密度进行变化判别,将概率密度的比较转化成核函数的形式,利用核函数的相似度量功能进行变化判别,通过指定的核函数避开概率密度的估计,达到概率密度比较的目的。  相似文献   

3.
一种遥感影像核变化检测方法   总被引:1,自引:0,他引:1  
提出了一种新的遥感影像核变化检测方法。该方法是将原始空间不同时相的输入矢量通过核函数非线性映射到高维特征空间,然后在高维特征空间中通过传统变化检测方法处理得到新的输入矢量,最后通过半监督的单类支持向量机算法对新的输入矢量构造变化区域与非变化区域的最优分割超平面。试验证实,本文的核变化检测方法具有较高的检测精度和效率。  相似文献   

4.
This letter proposes a nonlinear version of the eigenspace separation transform (EST) for subspace anomaly detection in hyperspectral imaging. The EST is defined in terms of the eigenvectors of the difference correlation matrix (DCOR) obtained using the data from the two classes. Using ideas found in the machine learning literature (i.e., the kernel trick), a nonlinear version-kernel EST (KEST)-is achieved by expressing the DCOR in terms of dot products in feature space and replacing all dot products with a Mercer kernel function that is defined in terms of input data space. Experimental results indicate that KEST outperforms many other commonly used subspace anomaly detection algorithms.  相似文献   

5.
高光谱遥感影像具有丰富的光谱信息,在地物分类识别方面具有明显的优势。针对复杂高光谱影像分类问题,应用了一种广义判别分析特征提取技术。将输入样本通过非线性函数映射到特征空间,在特征空间中应用线性判别特征提取方法;算法求解过程中涉及到在特征空间的内积用核函数代替,简化计算的同时也使得算法与非线性函数的具体形式无关。通过影像分类试验表明,该方法较常用特征提取方法更有利于分类精度的提高。  相似文献   

6.
This paper presents a kernel-based approach for the change detection of remote sensing images. It detects change by comparing the probability density (PD), expressed as kernel functions, of the feature vector extracted from bi-temporal images. PD is compared by defined kernel functions without immediate PD estimation. This algorithm is model-free and it can process multidimensional data, and is fit for the images with rich texture in particular. Experimental results show that overall accuracy of the algorithm is 98.9%, a little bit better than that of the change vector analysis and classification comparison method, which is 96.7 and 95.9% respectively.  相似文献   

7.
冯永玖  刘妙龙 《测绘科学》2011,36(3):216-218
利用元胞自动机(Cellular Automata,CA)模拟土地利用变化,已经成为认识和理解其复杂动态演化过程的有效手段.传统的元胞自动机基于线性转换规则,较难表达土地利用变化的非线性边界问题.本文研究利用最小二乘支持向量机方法(LS-SVM),将原空间下的非线性可分问题,通过高斯径向基核函数映射到高维特征空间,简化...  相似文献   

8.
In this research, an object-oriented image classification framework was developed which incorporates nonlinear scale-space filtering into the multi-scale segmentation and classification procedures. Morphological levelings, which possess a number of desired spatial and spectral properties, were associated with anisotropically diffused markers towards the construction of nonlinear scale spaces. Image objects were computed at various scales and were connected to a kernel-based learning machine for the classification of various earth-observation data from both active and passive remote sensing sensors. Unlike previous object-based image analysis approaches, the scale hierarchy is implicitly derived from scale-space representation properties. The developed approach does not require the tuning of any parameter—of those which control the multi-scale segmentation and object extraction procedure, like shape, color, texture, etc. The developed object-oriented image classification framework was applied on a number of remote sensing data from different airborne and spaceborne sensors including SAR images, high and very high resolution panchromatic and multispectral aerial and satellite datasets. The very promising experimental results along with the performed qualitative and quantitative evaluation demonstrate the potential of the proposed approach.  相似文献   

9.
谭琨  杜培军 《测绘学报》2011,40(2):142-147
针对支持向量机用于高光谱遥感影像分类存在的分类精度不高、参数选择困难等问题,提出一种再生核Hilbert空间的小波核.其可以逼近任意非线性函数,能够有效改进参数估计的效果,进而实现基于再生核Hilbert空间的小波核函数支持向量机(小波支持向量机).并选取北京昌平地区的国产高光谱数据operational modula...  相似文献   

10.
11.
苏红军  顾梦宇 《遥感学报》2021,25(5):1055-1070
目前,高光谱遥感特征提取方法往往因受到噪声的干扰而导致降维效果欠佳.近年来,判别局部对齐DLA(Discriminative Locality Alignment)由于可以处理非线性分布样本、保留局部判别信息,同时避免矩阵奇异性问题,受到了很多学者的关注;但该方法无法有效估计和减少噪声对高光谱遥感影像的影响.针对以上问...  相似文献   

12.
In this letter, a new nonlinear approach based on a combination of the fuzzy c-means clustering (FCMC), feature vector selection and principal component analysis (PCA) is proposed to extract features of multispectral images when a very large number of samples need to be processed. The main contribution of this letter is to provide a preprocessing method for classifying these images with higher accuracy compared to the single PCA and kernel PCA. Finally, some experimental results demonstrate that our proposed approach is effective and efficient in analyzing multispectral images.  相似文献   

13.
为了进一步提高基于独立分量分析ICA(Independent Component Analysis)的遥感图像变化检测精确度,更好地实现地表覆盖的动态监测,将多尺度几何分析和核独立分量分析KICA(Kernel Independent Component Analysis)相结合应用于遥感图像的地表覆盖变化检测。首先利用Contourlet变换、复Contourlet变换CCT(Complex Contourlet Transform)、非下采样Contourlet变换NSCT(Nonsubsampled Contourlet Transform)等多尺度几何分析对土地遥感图像进行多尺度分解;然后对分解后的数据进行核独立分量分析,通过核函数将数据映射到高维特征空间中,再在该空间中用ICA方法分离出互相独立的分量;最后将分离后的地表变化分量转化为图像分量,再采用最大类间方差法对变化图像进行分割,实现地表覆盖的变化检测。给出了本文方法和近年来提出的基于ICA、基于KICA、基于小波变换和ICA等变化检测方法的实验结果,并进行了分析和定量比较。实验结果表明,基于多尺度几何分析和KICA的变化检测方法能更好地分离出遥感图像的变化信息,其中基于NSCT和KICA方法的错判和漏检误差最小,且在边缘细节方面处理得更好,而基于Contourlet变换和KICA方法的检测效率相对较高。  相似文献   

14.
This article presents a novel supervised target detection approach on hyperspectral images based on Fukunaga–Koontz Transform (FKT) with compositional kernel combination. The Fukunaga–Koontz Transform is one of the most effective techniques for solving problems that involve two-pattern characteristics. To capture nonlinear properties of data, researchers have extended FKT to kernel FKT (KFKT) by means of kernel machines. However, the performance of KFKT depends on choosing convenient kernel functions and/or selection of the proper parameter(s). In this work, instead of selecting a single kernel for nonlinear version of FKT, we have applied a compositional kernel combination approach to capture the underlying local distributions of hyperspectral remote sensing data. Optimal parameter selection for each kernel function is achieved applying an evolutionary technique called differential evolution algorithm. The proposed new nonlinear target detection algorithm is tested for hyperspectral images. The experimental results verify that the proposed target detection algorithm has effective and promising performance compared to the conventional version for supervised target detection applications.  相似文献   

15.
We propose a kernel nonlocal joint collaborative representation classification method based on column generation for hyperspectral imagery. The proposed approach first maps the original spectral space to a higher implicit kernel space by directly taking the similarity measures between spectral pixels as a feature, and then utilizes a nonlocal joint collaborative regression model for kernel signal reconstruction and the subsequent pixel classification. We also develop two kinds of specific radial basis function kernels for measuring the similarities. The experimental results indicate that the proposed algorithms obtain a competitive performance and outperform other state-of-the-art regression-based classifiers and the classical support vector machines classifier.  相似文献   

16.
李东宸  向文豪  党倩楠  吴艳 《测绘学报》1957,49(12):1583-1590
针对SAR与可见光图像配准中存在的非线性灰度差异与斑点噪声,同时考虑不同的成像视角问题,提出了基于均匀分布与结构描述ASIFT的SAR与可见光图像配准算法。该算法首先采用引导滤波建立引导尺度空间以达到噪声抑制与边缘保持,在特征点提取阶段,由于非线性灰度差异引入相位一致性强度信息,并与尺度空间网格划分相结合,指导筛选图像中均匀特征点的获取;然后在特征描述阶段,引入扩展相位一致性方法计算SAR与可见光图像的一致性梯度幅值和方向,提高了主方向和描述符的准确性;最后利用Optimal-RANSAC进行特征描述符匹配实现有效配准。通过对4组实测图像进行试验及结果分析,证明该算法相比SAR-SIFT与传统ASIFT算法具有更准确的配准精度。  相似文献   

17.
在遥感影像自动分类中仅使用光谱特征很难产生正确的分类,OLI影像是波段数较多的多光谱影像,如果增加纹理、几何等多种特征以提高分类精度,就会使得特征的维度很高.支持向量机善于解决小样本、非线性和高维的影像分类问题,但是核函数和参数的设置只能依靠实验来获得.文中在OLI影像中提取了23个特征,逐个测试核函数和参数值对分类结果的影响.研究的主要结论如下:RBF核的支持向量机分类精度最高,Sigmoid核支持向量机分类精度最低;核函数的选择对分类精度的影响最大;核函数和参数值的变化不会影响重要特征的使用,3种核的支持向量机分类所使用的重要特征基本一致.  相似文献   

18.
图像分类中基于核映射的光谱匹配度量方法   总被引:1,自引:0,他引:1  
夏列钢  王卫红  胡晓东  骆剑承 《测绘学报》2012,41(4):591-596,604
针对多光谱遥感数据特点利用SSV匹配技术改进高斯核函数得到新的KSSV函数,然后在由KSSV核函数映射得到的高维空间中利用SAM匹配技术代替基于欧氏距离的相似性度量。如此可以充分挖掘多光谱影像中的波谱特征信息并有效利用,提高模式识别方法应用的有效性。将此方法分别应用于非监督分类(k均值)与监督分类(最小距离、SVM)的试验表明,改进度量的分类方法可显著提高地类间的可区分度并有效降低类内的不一致性,更有效针对多光谱遥感影像中的地物类型,获得较好的精度改进。  相似文献   

19.
This letter presents two kernel-based methods for semisupervised regression. The methods rely on building a graph or hypergraph Laplacian with both the available labeled and unlabeled data, which is further used to deform the training kernel matrix. The deformed kernel is then used for support vector regression (SVR). Given the high computational burden involved, we present two alternative formulations based on the Nystrom method and the incomplete Cholesky factorization to achieve operational processing times. The semisupervised SVR algorithms are successfully tested in multiplatform leaf area index estimation and oceanic chlorophyll concentration prediction. Experiments are carried out with both multispectral and hyperspectral data, demonstrating good generalization capabilities when a low number of labeled samples are available, which is usually the case in biophysical parameter retrieval.  相似文献   

20.
基于核Fisher判别分析的高光谱遥感影像分类   总被引:5,自引:2,他引:3  
高光谱遥感技术,将反映目标辐射特性的光谱信息与反映目标空间位置关系的图像信息有机地结合在一起.高光谱影像具有丰富的光谱信息,较全色、多光谱影像能够更好的进行地面目标的分类识别.在介绍核Fisher判别分析算法的基础上,选用径向基核函数,使用一对一或一对余构造多类构造法,并利用交叉验证网格搜索法优化核函数参数,构建了快速稳定的多类核Fisher判别分析分类器.通过OMIS和AVIRIS影像的分类实验,表明了核Fisher判别分析与支持向量机的分类精度相当,但是所需的训练时间较短.  相似文献   

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