期刊文献+
共找到282篇文章
< 1 2 15 >
每页显示 20 50 100
Multi-task Joint Sparse Representation Classification Based on Fisher Discrimination Dictionary Learning 被引量:6
1
作者 Rui Wang Miaomiao Shen +1 位作者 Yanping Li Samuel Gomes 《Computers, Materials & Continua》 SCIE EI 2018年第10期25-48,共24页
Recently,sparse representation classification(SRC)and fisher discrimination dictionary learning(FDDL)methods have emerged as important methods for vehicle classification.In this paper,inspired by recent breakthroughs ... Recently,sparse representation classification(SRC)and fisher discrimination dictionary learning(FDDL)methods have emerged as important methods for vehicle classification.In this paper,inspired by recent breakthroughs of discrimination dictionary learning approach and multi-task joint covariate selection,we focus on the problem of vehicle classification in real-world applications by formulating it as a multi-task joint sparse representation model based on fisher discrimination dictionary learning to merge the strength of multiple features among multiple sensors.To improve the classification accuracy in complex scenes,we develop a new method,called multi-task joint sparse representation classification based on fisher discrimination dictionary learning,for vehicle classification.In our proposed method,the acoustic and seismic sensor data sets are captured to measure the same physical event simultaneously by multiple heterogeneous sensors and the multi-dimensional frequency spectrum features of sensors data are extracted using Mel frequency cepstral coefficients(MFCC).Moreover,we extend our model to handle sparse environmental noise.We experimentally demonstrate the benefits of joint information fusion based on fisher discrimination dictionary learning from different sensors in vehicle classification tasks. 展开更多
关键词 Multi-sensor fusion fisher discrimination dictionary learning(FDDL) vehicle classification sensor networks sparse representation classification(SRC)
在线阅读 下载PDF
Hyperspectral image classification based on spatial and spectral features and sparse representation 被引量:4
2
作者 杨京辉 王立国 钱晋希 《Applied Geophysics》 SCIE CSCD 2014年第4期489-499,511,共12页
To minimize the low classification accuracy and low utilization of spatial information in traditional hyperspectral image classification methods, we propose a new hyperspectral image classification method, which is ba... To minimize the low classification accuracy and low utilization of spatial information in traditional hyperspectral image classification methods, we propose a new hyperspectral image classification method, which is based on the Gabor spatial texture features and nonparametric weighted spectral features, and the sparse representation classification method(Gabor–NWSF and SRC), abbreviated GNWSF–SRC. The proposed(GNWSF–SRC) method first combines the Gabor spatial features and nonparametric weighted spectral features to describe the hyperspectral image, and then applies the sparse representation method. Finally, the classification is obtained by analyzing the reconstruction error. We use the proposed method to process two typical hyperspectral data sets with different percentages of training samples. Theoretical analysis and simulation demonstrate that the proposed method improves the classification accuracy and Kappa coefficient compared with traditional classification methods and achieves better classification performance. 展开更多
关键词 HYPERSPECTRAL classification sparse representation spatial features spectral features
在线阅读 下载PDF
Weighted Sparse Image Classification Based on Low Rank Representation 被引量:5
3
作者 Qidi Wu Yibing Li +1 位作者 Yun Lin Ruolin Zhou 《Computers, Materials & Continua》 SCIE EI 2018年第7期91-105,共15页
The conventional sparse representation-based image classification usually codes the samples independently,which will ignore the correlation information existed in the data.Hence,if we can explore the correlation infor... The conventional sparse representation-based image classification usually codes the samples independently,which will ignore the correlation information existed in the data.Hence,if we can explore the correlation information hidden in the data,the classification result will be improved significantly.To this end,in this paper,a novel weighted supervised spare coding method is proposed to address the image classification problem.The proposed method firstly explores the structural information sufficiently hidden in the data based on the low rank representation.And then,it introduced the extracted structural information to a novel weighted sparse representation model to code the samples in a supervised way.Experimental results show that the proposed method is superiority to many conventional image classification methods. 展开更多
关键词 Image classification sparse representation low-rank representation numerical optimization.
在线阅读 下载PDF
Low-Rank and Sparse Representation with Adaptive Neighborhood Regularization for Hyperspectral Image Classification 被引量:8
4
作者 Zhaohui XUE Xiangyu NIE 《Journal of Geodesy and Geoinformation Science》 2022年第1期73-90,共18页
Low-Rank and Sparse Representation(LRSR)method has gained popularity in Hyperspectral Image(HSI)processing.However,existing LRSR models rarely exploited spectral-spatial classification of HSI.In this paper,we proposed... Low-Rank and Sparse Representation(LRSR)method has gained popularity in Hyperspectral Image(HSI)processing.However,existing LRSR models rarely exploited spectral-spatial classification of HSI.In this paper,we proposed a novel Low-Rank and Sparse Representation with Adaptive Neighborhood Regularization(LRSR-ANR)method for HSI classification.In the proposed method,we first represent the hyperspectral data via LRSR since it combines both sparsity and low-rankness to maintain global and local data structures simultaneously.The LRSR is optimized by using a mixed Gauss-Seidel and Jacobian Alternating Direction Method of Multipliers(M-ADMM),which converges faster than ADMM.Then to incorporate the spatial information,an ANR scheme is designed by combining Euclidean and Cosine distance metrics to reduce the mixed pixels within a neighborhood.Lastly,the predicted labels are determined by jointly considering the homogeneous pixels in the classification rule of the minimum reconstruction error.Experimental results based on three popular hyperspectral images demonstrate that the proposed method outperforms other related methods in terms of classification accuracy and generalization performance. 展开更多
关键词 Hyperspectral Image(HSI) spectral-spatial classification Low-Rank and sparse representation(LRSR) Adaptive Neighborhood Regularization(ANR)
在线阅读 下载PDF
Metasample-Based Robust Sparse Representation for Tumor Classification 被引量:1
5
作者 Bin Gan Chun-Hou Zheng Jin-Xing Liu 《Engineering(科研)》 2013年第5期78-83,共6页
In this paper, based on sparse representation classification and robust thought, we propose a new classifier, named MRSRC (Metasample Based Robust Sparse Representation Classificatier), for DNA microarray data classif... In this paper, based on sparse representation classification and robust thought, we propose a new classifier, named MRSRC (Metasample Based Robust Sparse Representation Classificatier), for DNA microarray data classification. Firstly, we extract Metasample from trainning sample. Secondly, a weighted matrix W is added to solve an l1-regular- ized least square problem. Finally, the testing sample is classified according to the sparsity coefficient vector of it. The experimental results on the DNA microarray data classification prove that the proposed algorithm is efficient. 展开更多
关键词 DNA MICROARRAY DATA sparse representation classification MRSRC ROBUST
在线阅读 下载PDF
Integrating absolute distances in collaborative representation for robust image classification
6
作者 Shaoning Zeng Xiong Yang +1 位作者 Jianping Gou Jiajun Wen 《CAAI Transactions on Intelligence Technology》 2016年第2期189-196,共8页
Conventional sparse representation based classification (SRC) represents a test sample with the coefficient solved by each training sample in all classes. As a special version and improvement to SRC, collaborative r... Conventional sparse representation based classification (SRC) represents a test sample with the coefficient solved by each training sample in all classes. As a special version and improvement to SRC, collaborative representation based classification (CRC) obtains representation with the contribution from all training samples and produces more promising results on facial image classification. In the solutions of representation coefficients, CRC considers original value of contributions from all samples. However, one prevalent practice in such kind of distance-based methods is to consider only absolute value of the distance rather than both positive and negative values. In this paper, we propose an novel method to improve collaborative representation based classification, which integrates an absolute distance vector into the residuals solved by collaborative representation. And we named it AbsCRC. The key step in AbsCRC method is to use factors a and b as weight to combine CRC residuals rescrc with absolute distance vector disabs and generate a new dviaetion r = a·rescrc b.disabs, which is in turn used to perform classification. Because the two residuals have opposite effect in classification, the method uses a subtraction operation to perform fusion. We conducted extensive experiments to evaluate our method for image classification with different instantiations. The experimental results indicated that it produced a more promising result of classification on both facial and non-facial images than original CRC method. 展开更多
关键词 sparse representation Collaborative representation INTEGRATION Image classification Face recognition
在线阅读 下载PDF
A new discriminative sparse parameter classifier with iterative removal for face recognition
7
作者 TANG De-yan ZHOU Si-wang +2 位作者 LUO Meng-ru CHEN Hao-wen TANG Hui 《Journal of Central South University》 SCIE EI CAS CSCD 2022年第4期1226-1238,共13页
Face recognition has been widely used and developed rapidly in recent years.The methods based on sparse representation have made great breakthroughs,and collaborative representation-based classification(CRC)is the typ... Face recognition has been widely used and developed rapidly in recent years.The methods based on sparse representation have made great breakthroughs,and collaborative representation-based classification(CRC)is the typical representative.However,CRC cannot distinguish similar samples well,leading to a wrong classification easily.As an improved method based on CRC,the two-phase test sample sparse representation(TPTSSR)removes the samples that make little contribution to the representation of the testing sample.Nevertheless,only one removal is not sufficient,since some useless samples may still be retained,along with some useful samples maybe being removed randomly.In this work,a novel classifier,called discriminative sparse parameter(DSP)classifier with iterative removal,is proposed for face recognition.The proposed DSP classifier utilizes sparse parameter to measure the representation ability of training samples straight-forward.Moreover,to avoid some useful samples being removed randomly with only one removal,DSP classifier removes most uncorrelated samples gradually with iterations.Extensive experiments on different typical poses,expressions and noisy face datasets are conducted to assess the performance of the proposed DSP classifier.The experimental results demonstrate that DSP classifier achieves a better recognition rate than the well-known SRC,CRC,RRC,RCR,SRMVS,RFSR and TPTSSR classifiers for face recognition in various situations. 展开更多
关键词 collaborative representation-based classification discriminative sparse parameter classifier face recognition iterative removal sparse representation two-phase test sample sparse representation
在线阅读 下载PDF
Robust Hierarchical Framework for Image Classification via Sparse Representation 被引量:4
8
作者 左圆圆 张钹 《Tsinghua Science and Technology》 SCIE EI CAS 2011年第1期13-21,共9页
The sparse representation-based classification algorithm has been used for human face recognition. But an image database was restricted to human frontal faces with only slight illumination and expression changes. Crop... The sparse representation-based classification algorithm has been used for human face recognition. But an image database was restricted to human frontal faces with only slight illumination and expression changes. Cropping and normalization of the face needs to be done beforehand. This paper uses a sparse representation-based algorithm for generic image classification with some intra-class variations and background clutter. A hierarchical framework based on the sparse representation is developed which flexibly combines different global and local features. Experiments with the hierarchical framework on 25 object categories selected from the Caltech101 dataset show that exploiting the advantage of local features with the hierarchical framework improves the classification performance and that the framework is robust to image occlusions, background clutter, and viewpoint changes. 展开更多
关键词 image classification keypoint detector keypoint descriptor sparse representation
原文传递
Discriminative Structured Dictionary Learning for Image Classification
9
作者 王萍 兰俊花 +1 位作者 臧玉卫 宋占杰 《Transactions of Tianjin University》 EI CAS 2016年第2期158-163,共6页
In this paper, a discriminative structured dictionary learning algorithm is presented. To enhance the dictionary's discriminative power, the reconstruction error, classification error and inhomogeneous representat... In this paper, a discriminative structured dictionary learning algorithm is presented. To enhance the dictionary's discriminative power, the reconstruction error, classification error and inhomogeneous representation error are integrated into the objective function. The proposed approach learns a single structured dictionary and a linear classifier jointly. The learned dictionary encourages the samples from the same class to have similar sparse codes, and the samples from different classes to have dissimilar sparse codes. The solution to the objective function is achieved by employing a feature-sign search algorithm and Lagrange dual method. Experimental results on three public databases demonstrate that the proposed approach outperforms several recently proposed dictionary learning techniques for classification. 展开更多
关键词 sparse representation dictionary learning sparse coding image classification
在线阅读 下载PDF
Semi-Supervised Dimensionality Reduction of Hyperspectral Image Based on Sparse Multi-Manifold Learning
10
作者 Hong Huang Fulin Luo +1 位作者 Zezhong Ma Hailiang Feng 《Journal of Computer and Communications》 2015年第11期33-39,共7页
In this paper, we proposed a new semi-supervised multi-manifold learning method, called semi- supervised sparse multi-manifold embedding (S3MME), for dimensionality reduction of hyperspectral image data. S3MME exploit... In this paper, we proposed a new semi-supervised multi-manifold learning method, called semi- supervised sparse multi-manifold embedding (S3MME), for dimensionality reduction of hyperspectral image data. S3MME exploits both the labeled and unlabeled data to adaptively find neighbors of each sample from the same manifold by using an optimization program based on sparse representation, and naturally gives relative importance to the labeled ones through a graph-based methodology. Then it tries to extract discriminative features on each manifold such that the data points in the same manifold become closer. The effectiveness of the proposed multi-manifold learning algorithm is demonstrated and compared through experiments on a real hyperspectral images. 展开更多
关键词 HYPERSPECTRAL IMAGE classification Dimensionality Reduction Multiple MANIFOLDS Structure sparse representation SEMI-SUPERVISED Learning
在线阅读 下载PDF
Spatial-Aware Supervised Learning for Hyper-Spectral Image Classification Comprehensive Assessment
11
作者 SOOMRO Bushra Naz XIAO Liang +1 位作者 SOOMRO Shahzad Hyder MOLAEI Mohsen 《Journal of Donghua University(English Edition)》 EI CAS 2016年第6期954-960,共7页
A comprehensive assessment of the spatial.aware mpervised learning algorithms for hyper.spectral image (HSI) classification was presented. For this purpose, standard support vector machines ( SVMs ), mudttnomial l... A comprehensive assessment of the spatial.aware mpervised learning algorithms for hyper.spectral image (HSI) classification was presented. For this purpose, standard support vector machines ( SVMs ), mudttnomial logistic regression ( MLR ) and sparse representation (SR) based supervised learning algorithm were compared both theoretically and experimentally. Performance of the discussed techniques was evaluated in terms of overall accuracy, average accuracy, kappa statistic coefficients, and sparsity of the solutions. Execution time, the computational burden, and the capability of the methods were investigated by using probabilistie analysis. For validating the accuracy a classical benchmark AVIRIS Indian pines data set was used. Experiments show that integrating spectral.spatial context can further improve the accuracy, reduce the misclassltication error although the cost of computational time will be increased. 展开更多
关键词 learning algorithms hyper-spectral image classification support vector machine(SVM) multinomial logistic regression(MLR) elastic net regression(ELNR) sparse representation(SR) spatial-aware
在线阅读 下载PDF
Weighted average integration of sparse representation and collaborative representation for robust face recognition 被引量:1
12
作者 Shaoning Zeng Yang Xiong 《Computational Visual Media》 2016年第4期357-365,共9页
Sparse representation is a significant method to perform image classification for face recognition. Sparsity of the image representation is the key factor for robust image classification.As an improvement to sparse re... Sparse representation is a significant method to perform image classification for face recognition. Sparsity of the image representation is the key factor for robust image classification.As an improvement to sparse representation-based classification, collaborative representation is a newer method for robust image classification. Training samples of all classes collaboratively contribute together to represent one single test sample. The ways of representing a test sample in sparse representation and collaborative representation are very different, so we propose a novel method to integrate both sparse and collaborative representations to provide improved results for robust face recognition.The method first computes a weighted average of the representation coefficients obtained from two conventional algorithms, and then uses it for classification. Experiments on several benchmark face databases show that our algorithm outperforms both sparse and collaborative representation-based classification algorithms, providing at least a 10%improvement in recognition accuracy. 展开更多
关键词 sparse representation collaborative representation image classification face recognition
原文传递
基于张量字典学习的高光谱图像稀疏表示分类 被引量:2
13
作者 宫学亮 李玉 +2 位作者 贾淑涵 赵泉华 王丽英 《光谱学与光谱分析》 北大核心 2025年第3期798-807,共10页
高光谱图像因其蕴含十分丰富的光谱和空间信息已被广泛应用于生产生活的各个领域。为了充分挖掘高光谱图像中蕴含的光谱和空间信息,从高光谱数据固有的三维属性出发,以空-谱张量为基本处理单元,提出一种基于张量字典学习的稀疏表示分类(... 高光谱图像因其蕴含十分丰富的光谱和空间信息已被广泛应用于生产生活的各个领域。为了充分挖掘高光谱图像中蕴含的光谱和空间信息,从高光谱数据固有的三维属性出发,以空-谱张量为基本处理单元,提出一种基于张量字典学习的稀疏表示分类(Tensor-DLSRC)算法,以提高高光谱图像分类精度。首先,构建以像素及其空间邻域像素光谱向量组成的像素空-谱张量;其次,将作为训练样本像素的空-谱张量按照不同维度展开成矩阵,并以其列向量均值作为字典原子组成初始化张量字典;同时,在张量稀疏性约束条件下构建张量稀疏表示(Tensor-SR)模型,并利用张量字典学习算法学习一组能够精确刻画该类张量空-谱特征的字靛矩阵;最后,对待分类像素利用Tensor-SR模型求解其空-谱张量的稀疏表示系数张量,根据重构残差最小化原则确定该像素类别。为了分析参数对提出算法分类精度的影响,在进行分类对比实验之前,通过一系列实验分别讨论训练样本数M、邻域窗口尺寸(2δ+1)×(2δ+1)、字典学习阶段的稀疏度μ1和稀疏表示阶段的稀疏度μ2等参数对总体分类精度(OA)的影响。为了验证提出算法的有效性,分别在Indian Pines、Salinas和Xuzhou三个高光谱数据上进行实验,对比分析本算法与基于光谱向量的SRC算法和DLSRC算法、增加邻域空间信息的JSRC算法和DLJSRC算法和基于空-谱张量的Tensor-DLSRC算法等五种算法的分类结果,并采用基于混淆矩阵的平均准确率(APR)、平均精度(PA)、OA和Kappa系数对分类结果定量分析。所提出的Tensor-DLSRC算法在OA和Kappa系数的平均值水平是六种算法中最高的,且具有最小的标准差,说明本算法与五种其他算法相比能够提供更准确且稳定的分类结果。 展开更多
关键词 高光谱图像 空-谱张量 稀疏表示 张量字典学习 张量稀疏表示分类
在线阅读 下载PDF
引信目标与干扰信号稀疏分类识别方法 被引量:1
14
作者 刘冰 郝新红 +2 位作者 秦高林 时明心 刘佳琪 《北京航空航天大学学报》 北大核心 2025年第2期498-506,共9页
为提升复杂电磁环境战场中调频无线电引信的抗干扰能力,基于稀疏表示理论,将稀疏表示系数重构用于调频无线电的目标和干扰信号分类识别,提出一种目标信号和扫频式干扰信号的分类识别方法,解决了调频无线电引信的抗干扰能力不足的问题。... 为提升复杂电磁环境战场中调频无线电引信的抗干扰能力,基于稀疏表示理论,将稀疏表示系数重构用于调频无线电的目标和干扰信号分类识别,提出一种目标信号和扫频式干扰信号的分类识别方法,解决了调频无线电引信的抗干扰能力不足的问题。采集了模拟目标及干扰信号作用于无线电引信的检波端输出信号,构建了目标信号过完备字典和干扰信号过完备字典,分别将测试信号在2类字典上进行稀疏分解并重构,依据重构误差对测试样本类别进行识别。结果表明:基于稀疏表示的调频无线电引信目标和干扰信号分类识别方法,可以对目标和干扰信号进行有效的识别,同时能够满足较低的虚警概率。研究成果对于调频无线电引信在复杂电磁环境中的抗干扰具有重要的借鉴意义。 展开更多
关键词 调频无线电引信 抗干扰 电子战 稀疏表示 信号分类
原文传递
双稀疏表示下海量病案信息多维属性分类方法
15
作者 倪红波 缪兵 李立果 《计算机仿真》 2025年第5期385-389,502,共6页
医疗卫生事业的高速发展致使病案信息海量增长,加剧了数据存储与挖掘难度,为提升病案信息属性分类性能,针对公共医疗数据集CMeEE,通过BDP数据优化算法与DSR特征稀疏算法,在SVM分类器的基础上,构建了BDP-DSR-SVM病案信息属性分类模型。... 医疗卫生事业的高速发展致使病案信息海量增长,加剧了数据存储与挖掘难度,为提升病案信息属性分类性能,针对公共医疗数据集CMeEE,通过BDP数据优化算法与DSR特征稀疏算法,在SVM分类器的基础上,构建了BDP-DSR-SVM病案信息属性分类模型。模型首先基于Z-SCORE标准化算法与LOF离群识别算法,对数据集进行平滑、归一处理,并采用PEREASON分析算法,对多维数据集降维优化,提升数据计算效率;接着在L_(1)与L_(2)双稀疏表示算法的基础上,通过优化权重矩阵,提升数据稀疏特征,提高函数收敛度;最后利用SVM分类器,通过十折交叉优化参数寻优,在超参数gamma_(AVE)=0.3681,C_(AVE)=7.4219下,构建出BDP-DSR-SVM模型,完成病案信息输出分类挖掘输出。基线属性分类模型对比仿真结果说明,与AdaBoost、K-Means、BP、CNN与RF五类传统属性分类模型相比,BDP-DSR-SVM模型的P、R、F_(1)指标参数平均提升了9.67%、11.50%与9.44%,达91.49%、90.85%与91.17%,同时本文模型的分类时效性更高。提出算法在病案信息属性分类上具有更高的准确性、稳定性与综合性,同时具有较高的时效性,在医疗数据处理领域具有较高仿真意义。 展开更多
关键词 属性分类 病案信息 稀疏表示
在线阅读 下载PDF
基于空间相关性约束稀疏表示的高光谱图像分类 被引量:15
16
作者 刘建军 吴泽彬 +2 位作者 韦志辉 肖亮 孙乐 《电子与信息学报》 EI CSCD 北大核心 2012年第11期2666-2671,共6页
该文提出一种新的基于稀疏表示的高光谱图像分类方法。首先利用训练数据构造结构化字典,建立基于稀疏表示的高光谱图像分类模型;然后添加空间相关性约束项和训练数据的空间信息,提高稀疏表示模型分类的准确性;最后采用快速的交替方向乘... 该文提出一种新的基于稀疏表示的高光谱图像分类方法。首先利用训练数据构造结构化字典,建立基于稀疏表示的高光谱图像分类模型;然后添加空间相关性约束项和训练数据的空间信息,提高稀疏表示模型分类的准确性;最后采用快速的交替方向乘子法求解模型。实验结果表明:该文方法能够有效提高分类精度,且分类结果稳定。 展开更多
关键词 高光谱图像 稀疏表示 分类 空间相关性
在线阅读 下载PDF
基于多种植被指数信息与联合稀疏表示的红树林种类识别 被引量:10
17
作者 苏岫 耿杰 +2 位作者 马晓瑞 王洪玉 王祥 《海洋环境科学》 CAS CSCD 北大核心 2017年第1期114-120,共7页
红树林种类识别对于研究红树林生态系统的变化具有重要意义。本文以广西铁山港红树林区为研究区域,以国产资源三号测绘卫星数据为数据源,分析区内各种红树林的光谱特性,并结合多项植被指数(RVI,NDVI,VARI和NDGI)信息,采用联合稀疏表示... 红树林种类识别对于研究红树林生态系统的变化具有重要意义。本文以广西铁山港红树林区为研究区域,以国产资源三号测绘卫星数据为数据源,分析区内各种红树林的光谱特性,并结合多项植被指数(RVI,NDVI,VARI和NDGI)信息,采用联合稀疏表示分类器进行红树林种类遥感识别。本文主要分析了桐花树、海漆、白骨壤、红海榄、秋茄、海桑、木榄这7种红树林种类以及陆地灌丛、泥滩、草地这些非红树林种类的几项植被指数,并结合多光谱图像的几何空间与光谱特征空间,采用联合稀疏表示算法进行红树林种类分类。利用组合光谱和4种植被指数信息进行分类可以达到最好的分类效果,总体精度为95.37%,kappa系数为0.9347。实验结果表明:光谱特征结合植被指数信息进行分类能提高分类精度,四种植被指数中NDVI对于区分红树林种类具有更大的贡献,联合稀疏表示分类器在红树林种类识别中表现出优异的分类效果。 展开更多
关键词 红树林 稀疏表示 植被指数 资源三号 遥感分类
原文传递
Gabor特征集结合判别式字典学习的稀疏表示图像识别 被引量:23
18
作者 胡正平 徐波 白洋 《中国图象图形学报》 CSCD 北大核心 2013年第2期189-194,共6页
稀疏编码中字典的选择无论对图像重建还是模式分类都有重要影响,为此提出Gabor特征集结合判别式字典学习的稀疏表示图像识别算法。考虑到Gabor局部特征对光照、表情和姿态等变化的鲁棒性,首先提取图像对应不同方向、不同尺度的多个Gabo... 稀疏编码中字典的选择无论对图像重建还是模式分类都有重要影响,为此提出Gabor特征集结合判别式字典学习的稀疏表示图像识别算法。考虑到Gabor局部特征对光照、表情和姿态等变化的鲁棒性,首先提取图像对应不同方向、不同尺度的多个Gabor特征;然后将降维的增广Gabor特征矩阵作为初始特征字典,通过对该字典的学习得到字典原子对应类别标签的新结构化字典,新字典中特定类的子字典对相关的类具有好的表示能力,同时应用Fisher判别约束编码系数,使它们具有小的类内散度和大的类间散度;最后同时用具有判别性的重构误差和编码系数来进行模式分类。基于3个数据库的实验结果表明本文方法具有可行性和有效性。 展开更多
关键词 稀疏表示 稀疏模式分类 GABOR特征 Fisher字典学习
原文传递
基于图像块分类稀疏表示的超分辨率重构算法 被引量:52
19
作者 练秋生 张伟 《电子学报》 EI CAS CSCD 北大核心 2012年第5期920-925,共6页
目前基于图像块稀疏表示的超分辨率重构算法对所有图像块都用同一字典表示,不能反映不同类型图像块间的差别.针对这一缺点,本文提出基于图像块分类稀疏表示的方法.该方法先利用图像局部特征将图像块分为平滑、边缘和不规则结构三种类型... 目前基于图像块稀疏表示的超分辨率重构算法对所有图像块都用同一字典表示,不能反映不同类型图像块间的差别.针对这一缺点,本文提出基于图像块分类稀疏表示的方法.该方法先利用图像局部特征将图像块分为平滑、边缘和不规则结构三种类型,其中边缘块细分为多个方向.然后利用稀疏表示方法对边缘和不规则结构块分别训练各自对应的低分辨率和高分辨率字典.重构时对平滑块利用简单双三次插值方法,边缘和不规则结构块由其对应的高、低分辨率字典通过正交匹配追踪算法重构.实验结果表明,与单字典稀疏表示算法相比,本文算法对图像边缘部分重构质量明显改善,同时重构速度显著提高. 展开更多
关键词 超分辨率 稀疏表示 块分类 正交匹配追踪
在线阅读 下载PDF
基于稀疏表示的绝缘子紫外图谱闪络状态分类评估方法 被引量:13
20
作者 刘云鹏 纪欣欣 +1 位作者 裴少通 王胜辉 《高电压技术》 EI CAS CSCD 北大核心 2018年第10期3352-3358,共7页
绝缘子运行状态的检测和故障诊断对于维持电力系统安全稳定运行至关重要。针对目前存在输变电绝缘子的紫外检测图像故障特征不明显、诊断准确率不高的问题,提出了一种基于稀疏表示法的绝缘子紫外图谱的闪络状态分类评估方法。通过字典... 绝缘子运行状态的检测和故障诊断对于维持电力系统安全稳定运行至关重要。针对目前存在输变电绝缘子的紫外检测图像故障特征不明显、诊断准确率不高的问题,提出了一种基于稀疏表示法的绝缘子紫外图谱的闪络状态分类评估方法。通过字典学习构建图谱信号自适应的过完备字典,采用加速近邻梯度算法和正交匹配追踪算法对待测紫外图像进行稀疏求解,依据稀疏矩阵的非零项进行分类诊断。结果表明,该方法的检测准确率较高,最高可达98%,其中正交匹配追踪算法依赖于字典的健全程度,当训练样本充足时算法识别时间仅为0.000 8 s。而加速近邻梯度算法则选取多个较优参量,适用于样本量较小的分类评估。此外,稀疏度参数敏感度较低,具有较好的鲁棒性。该算法同多分类支持向量机(M-SVM)算法相比,具有更好的表现性能,在绝缘子紫外检测分级预警和故障检测方面具有良好的应用前景。 展开更多
关键词 绝缘子 稀疏表示 紫外图谱 闪络分级 正交匹配追踪法 加速近邻梯度法
原文传递
上一页 1 2 15 下一页 到第
使用帮助 返回顶部