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1.
李吉明  贾森  彭艳斌 《光电工程》2012,39(11):88-86
高光谱遥感图像中包含有大量的高维数据,传统的有监督学习算法在对这些数据进行分类时要求获取足够多的有标记样本用于分类器的训练.然而,对高光谱图像中大量的复杂地物像元所属类别进行准确标注通常需要耗费极大的人力.在本文中,我们提出了一种基于半监督学习的光谱和纹理特征协同学习(STF-CT)--法,利用协同学习机制将高光谱图像光谱特征和空间纹理特征这两种不同的特征结合起来,用于小训练样本集下的高光谱图像数据分类问题.STF-CT算法充分利用了高光谱图像的光谱和纹理特征这两个独立视图,构建起一种有效的半监督分类方法,用于提升分类器在小训练样本集情况下的分类精度.实验结果表明该算法在小训练样本集下的高光谱地物分类问题上具有很好的效果.  相似文献   

2.
杨蕴睿  郑东文 《中国测试》2022,(12):162-171
针对现有基于协同表示的分类算法对于高光谱遥感图像的空间光谱信息利用不充分而造成较低分类精度的问题,该文提出一种空谱协同编码方法用于高光谱图像分类。算法首先利用空间光谱信息对图像进行加权滤波。随后,对于协同编码模型,将空间光谱信息转化为空间光谱权重以对模型进行正则约束。在Indian Pines和University of Pavia真实数据集上的实验结果表明提出的算法能分别获得98.82%和99.09%的总体精度。实验证明了所提出的算法对高光谱遥感图像进行分类的有效性。  相似文献   

3.
张晓宇 《高技术通讯》2011,(12):1312-1317
针对多标签图像分类问题的特点,提出了一种多视角二维主动学习(MV-2DAL)算法,以通过多视角学习与主动学习的有机结合,深入挖掘样本、标签、视角三个维度上的相关性和冗余性.此算法以样本-标签对作为基本标注单位,在每个视角内,利用二维主动学习的方法计算样本、标签维度上的不确定度;在不同视角间,通过多视角融合的方法计算跨视...  相似文献   

4.
为了提高图像超分辨效果,针对以往稀疏字典超分辨算法仅适用于单特征空间的问题,提出基于贝塔过程联合字典学习(BPJDL)的图像超分辨重建(SRR)方法。首先,根据图像退化模型生成训练样本图像,分别对高、低分辨率图像进行7×7分块,并利用吉布斯采样对图像块进行采样,生成字典训练样本。然后,依据贝塔过程先验模型,建立连接高、低分辨率图像空间的双参数联合稀疏字典,将字典稀疏系数分解为系数权值和字典原子的乘积,通过训练和更新字典,得到同时适用于两个特征空间的字典映射矩阵。最后,进行图像超分辨稀疏重构。实验结果表明:本文方法能以更小尺寸的稀疏字典重建超分辨图像,与当前最先进的稀疏表示超分辨算法相比,结果图像主观视觉上纹理细节信息更丰富,客观评价参数峰值信噪比(PSNR)提高约1.5 dB,结构相似性(SSIM)提高约0.02,超分辨重建时间降低约50 s。  相似文献   

5.
6.
基于支持向量数据描述(SVDD)的高光谱图像异常检测算法常常会因为背景样本中混入异常像元(野值)而导致检测概率下降.针对此问题,提出一种基于带野值的支持向量描述的检测算法,引入原点和少量已检测出来的异常像元作为异常样本,以改善算法对异常和背景数据的描述能力;同时为抑制错误样本的影响,将异常和背景样本偏离背景样本均值的距离映射作为各样本的加权系数.结果表明,新算法在低虚警概率下较之SVDD模型有更高的检测概率.利用真实数据进行实验证明了算法的有效性.  相似文献   

7.
通过分析线性混合模型及几何端元在空间投影中所具有的特性,提出了用于高光谱图像端元提取的分层查找法.该方法基于几何形态学与几何端元的概念,将确定单形体端点的过程分层处理,以实现对高光谱图像中端元的快速、准确估计.该方法不需要预先确定端元个数,而是在提取端元过程中自动调整端元个数.基于模拟数据与真实数据的实验的结果表明,在端元个数未知的情况下,分层查找法能够对高光谱图像中所包含的端元及端元个数给出较准确的快速估计,较好地解决了实际高光谱图像端元提取过程中端元个数难以确定的问题.  相似文献   

8.
高光谱图像在地物观测领域得到了广泛的应用。由于高光谱图像具有数据量大、波段间相关度高等特性,波段选择技术成为降低地物识别计算复杂度的重要方法。根据不同波段数据之间的非线性关系,提出了基于谱聚类(SC)的波段选择技术。该方法首先以波段图像为样本点生成近邻图和相似度矩阵,然后借助谱聚类方法将所有数据样本分成 k类,从中选择 k个代表波段参与后继的分类识别任务。实验数据表明,新方法减小了计算复杂度,提高了地物识别的精度。  相似文献   

9.
显著性目标检测是计算机视觉中一项重要的任务.基于彩色图像的显著性目标检测已经取得了很好的成果,但是在复杂场景中,基于彩色图像的目标检测方法会失效,例如当目标物体与周围环境有着相似的颜色、轮廓、纹理时.与彩色图像不同,高光谱图像同时记录目标的二维空间信息和一维光谱相应信息,可以刻画目标的材质特性,是处理这类问题的重要方式...  相似文献   

10.
基于局部特征空间相关核的图像目标分类   总被引:1,自引:0,他引:1  
为了描述局部特征在图像空间中相对位置关系,提出一种局部特征空间相关核(Spatial Correlation Kernel,SCK)用于图像目标分类.该方法首先提取并量化图像中的局部特征,再计算量化后的局部特征的空间位置自相关度,然后利用直方图交叉匹配两幅图像的空间位置自相关度得到局部特征空间相关核.该核充分利用局部特征的强分辨能力及其空间位置,且SCK具有线性计算复杂度,满足正定条件,可以运用于基于核的学习算法.本文将SCK嵌入支持向量机对公共数据库中图像目标进行分类,实验结果表明,SCK可以获得良好的时间效率和分类性能.  相似文献   

11.
Recently, the sparse representation (SR) based algorithms have gained much attention from the researchers in the area of image fusion (IF). The building of a compact discriminative dictionary plays a vital role in the sparse-based IF techniques. In this context, an efficient multimodal IF method based on improved dictionary learning is investigated. The key contributions of this paper are: (a) An improved KSVD algorithm is suggested for the dictionary learning process, (b) to reduce the computational time, only the informative patches are selected using energy feature, and (c) a novel region-based fusion scheme is suggested for the first time for the problem on hand. The suggested technique is tested with a number of multimodal images from Harvard Medical School brain database. The results are compared with state-of-the-art multiscale transform-based methods and modified SR-based methods. Unlike earlier methods, our proposed technique generates an adaptive dictionary through selection of informative patches only. This results in a compact dictionary with improved computational efficiency. The experimental results reveal that our approach outperforms other methods. The potential application of the suggested method could be in pathological images for follow-up study and better treatment planning.  相似文献   

12.
王红  孙同晶  刘桐 《声学技术》2020,39(5):552-558
主动声呐目标分类在军事和民用方面都有重要的应用和价值。文章基于稀疏表示理论,结合K-奇异值分解和正交匹配追踪算法,提出一种基于学习字典的稀疏表示分类方法(Dictionary Learning Sparse Representation Classification,DLSRC)。首先,利用K-奇异值分解算法训练各个类别目标回波信号,得到带有目标特征信息的类别字典,类别字典对信号具有良好表征能力并且带有目标类别信息;然后,利用正交匹配追踪算法和各个类别字典稀疏分解测试信号,得到各个类别字典下的稀疏系数后重构信号;最后,根据各个重构信号与测试信号的匹配度判定类别,得到分类准确率。结果显示,200个测试数据在信噪比分别为-5、-3、6 dB时,DLSRC法的分类准确率分别达到87%、89%、95.5%。不同信噪比下基于学习字典稀疏表示分类方法的准确率均高于已有的支持向量机(Support Vector Machine,SVM)、K-最近邻(K-Nearest Neighbor,KNN)和柔性最大值分类器(SoftMax)等分类方法,具有较好的分类性能。  相似文献   

13.
Biopsy is one of the most commonly used modality to identify breast cancer in women, where tissue is removed and studied by the pathologist under the microscope to look for abnormalities in tissue. This technique can be time-consuming, error-prone, and provides variable results depending on the expertise level of the pathologist. An automated and efficient approach not only aids in the diagnosis of breast cancer but also reduces human effort. In this paper, we develop an automated approach for the diagnosis of breast cancer tumors using histopathological images. In the proposed approach, we design a residual learning-based 152-layered convolutional neural network, named as ResHist for breast cancer histopathological image classification. ResHist model learns rich and discriminative features from the histopathological images and classifies histopathological images into benign and malignant classes. In addition, to enhance the performance of the developed model, we design a data augmentation technique, which is based on stain normalization, image patches generation, and affine transformation. The performance of the proposed approach is evaluated on publicly available BreaKHis dataset. The proposed ResHist model achieves an accuracy of 84.34% and an F1-score of 90.49% for the classification of histopathological images. Also, this approach achieves an accuracy of 92.52% and F1-score of 93.45% when data augmentation is employed. The proposed approach outperforms the existing methodologies in the classification of benign and malignant histopathological images. Furthermore, our experimental results demonstrate the superiority of our approach over the pre-trained networks, namely AlexNet, VGG16, VGG19, GoogleNet, Inception-v3, ResNet50, and ResNet152 for the classification of histopathological images.  相似文献   

14.
ABSTRACT

In this paper, we propose a robust subspace learning method, based on RPCA, named Robust Principal Component Analysis with Projection Learning (RPCAPL), which further improves the performance of feature extraction by projecting data samples into a suitable subspace. For Subspace Learning (SL) methods in clustering and classification tasks, it is also critical to construct an appropriate graph for discovering the intrinsic structure of the data. For this reason, we add a graph Laplacian matrix to the RPCAPL model for preserving the local geometric relationships between data samples and name the improved model as RPCAGPL, which takes all samples as nodes in the graph and treats affinity between pairs of connected samples as weighted edges. The RPCAGPL can not only globally capture the low-rank subspace structure of the data in the original space, but also locally preserve the neighbor relationship between the data samples.  相似文献   

15.
This paper presents a semisupervised dimensionality reduction (DR) method based on the combination of semisupervised learning (SSL) and metric learning (ML) (CSSLML-DR) in order to overcome some existing limitations in HSIs analysis. Specifically, CSSML focuses on the difficulties of high dimensionality of hyperspectral images (HSIs) data, the insufficient number of labelled samples and inappropriate distance metric. CSSLML aims to learn a local metrics under which the similar samples are pushed as close as possible, and simultaneously, the different samples are pulled away as far as possible. CSSLML constructs two local-reweighted dynamic graphs in an iterative two-steps approach: L-step and V-step. In L-step, the local between-class and within-class graphs are updated. In V-step, the transformation matrix and the reduced space are updated. The algorithm is repeated until a stopping criterion is satisfied. Experimental results on two well-known hyperspectral image data sets demonstrate the superiority of CSSLML algorithm compared to some traditional DR methods.  相似文献   

16.
《Advanced Powder Technology》2021,32(10):3885-3903
Mineral image segmentation plays a vital role in the realization of machine vision based intelligent ore sorting equipment. However, the existing image segmentation methods still cannot effectively solve the problem of adhesion and overlap between mineral particles, and the segmentation performance of small and irregular particles still needs to be improved. To overcome these bottlenecks, we propose a deep learning based image segmentation method to segment the key areas in mineral images using morphological transformation to process mineral image masks. This investigation explores four aspects of the deep learning-based mineral image segmentation model, including backbone selection, module configuration, loss function construction, and its application in mineral image classification. Specifically, referring to the designs of U-Net, FCN, Seg Net, PSP Net, and DeepLab Net, this experiment uses different backbones as Encoder to building ten mineral image segmentation models with different layers, structures, and sampling methods. Simultaneously, we propose a new loss function suitable for mineral image segmentation and compare CNNs-based segmentation models' training performance under different loss functions. The experiment results show that the proposed mineral image segmentation has excellent segmentation performance, effectively solves adhesion and overlap between adjacent particles without affecting the classification accuracy. By using the Mobile Net as backbone, the PSP Net and DeepLab can achieve a high segmentation performance in mineral image segmentation tasks, and the 15 × 15 is the most suitable size for erosion element structure to process the mask images of the segmentation models.  相似文献   

17.
Multi-modality medical image fusion (MMIF) procedures have been generally utilized in different clinical applications. MMIF can furnish an image with anatomical as well as physiological data for specialists that could advance the diagnostic procedures. Various models were proposed earlier related to MMIF though there is a need still exists to enhance the efficiency of the previous techniques. In this research, the authors proposed a novel fusion model based on optimal thresholding with deep learning concepts. An enhanced monarch butterfly optimization (EMBO) is utilized to decide the optimal threshold of fusion rules in shearlet transform. Then, low and high-frequency sub-bands were fused on the basis of feature maps and were given by the extraction part of the deep learning method. Here, restricted Boltzmann machine (RBM) was utilized to conduct the MMIF procedure. A benchmark dataset was utilized for training and testing purposes. The investigations were conducted utilizing a set of generally-utilized pre-enrolled CT and MR images that are publicly accessible. From the usage of fused low and high level frequency groups, the fused image can be attained. The simulation performance results were attained and the proposed model was proved to offer effective performance in terms of SD, edge quality (EQ), mutual information (MI), fusion factor (FF), entropy, correlation factor (CF), and spatial frequency (SF) with respective values being 97.78, 0.96, 5.71, 6.53, 7.43, 0.97, and 25.78 over the compared methods.  相似文献   

18.
基于卷积神经网络模型的遥感图像分类   总被引:2,自引:0,他引:2  
研究了遥感图像的分类,针对遥感图像的支持向量机(SVM)等浅层结构分类模型特征提取困难、分类精度不理想等问题,设计了一种卷积神经网络(CNN)模型,该模型包含输入层、卷积层、全连接层以及输出层,采用Soft Max分类器进行分类。选取2010年6月6日Landsat TM5富锦市遥感图像为数据源进行了分类实验,实验表明该模型采用多层卷积池化层能够有效地提取非线性、不变的地物特征,有利于图像分类和目标检测。针对所选取的影像,该模型分类精度达到94.57%,比支持向量机分类精度提高了5%,在遥感图像分类中具有更大的优势。  相似文献   

19.
Automated retinal disease detection and grading is one of the most researched areas in medical image analysis. In recent years, Deep Learning models have attracted much attention in this field. Hence, in this paper, we present a Deep Learning-based, lightweight, fully automated end-to-end diagnostic system for the detection of the two major retinal diseases, namely diabetic macular oedema (DME) and drusen macular degeneration (DMD). Early detection of these diseases is important to prevent vision impairment. Optical coherence tomography (OCT) is the main imaging technique for detecting these diseases. The model proposed in this work is based on residual blocks and channel attention modules. The performance of the model is evaluated using the publicly available Mendeley OCT dataset and the Duke dataset. We were able to achieve a classification accuracy of 99.5% in the Mendeley test dataset and 94.9% in the Duke dataset with the proposed model. For the application, we performed an extensive evaluation of pre-trained models (LeNet, AlexNet, VGG-16, ResNet50 and SE-ResNet). The proposed model has a much smaller number of trainable parameters and shows superior performance compared to existing methods.  相似文献   

20.
针对人-机器人语音交互中经过语音识别的文本指令,提出了一种利用汉语拼音中声韵母作为特征的深度学习文本分类模型。首先,以无人驾驶车语音导航控制为人机交互的应用背景,分析其文本指令结构并分别构建单一意图与复杂意图语料库;其次,在以字符作为文本分类特征的基础上,结合汉语拼音与英文单词的区别,提出了一种利用拼音声韵母字符作为中文文本分类的特征表示方法;然后,用门控递归单元(GRU)代替传统递归神经网络单元以解决其难以捕获长时间维度特征的不足,为提取信息的高阶特征、缩短特征序列长度并加快模型收敛速度,建立了一种结合卷积神经网络及GRU递归神经网络的深度学习文本分类模型。最后,为验证模型在处理长、短序列任务上的表现,在上述两个语料库上对提出的模型分别进行十折交叉测试,并与其他分类方法进行比较与分析,结果表明该模型显著地提高了分类准确率。  相似文献   

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