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1.
In this work, a new human face recognition algorithm based on bidirectional two dimensional principal component analysis (B2DPCA) and extreme learning machine (ELM) is introduced. The proposed method is based on curvelet image decomposition of human faces and a subband that exhibits a maximum standard deviation is dimensionally reduced using an improved dimensionality reduction technique. Discriminative feature sets are generated using B2DPCA to ascertain classification accuracy. Other notable contributions of the proposed work include significant improvements in classification rate, up to hundred folds reduction in training time and minimal dependence on the number of prototypes. Extensive experiments are performed using challenging databases and results are compared against state of the art techniques.  相似文献   

2.
In this paper, a novel hybrid method, which integrates an effective filter maximum relevance minimum redundancy (MRMR) and a fast classifier extreme learning machine (ELM), has been introduced for diagnosing erythemato-squamous (ES) diseases. In the proposed method, MRMR is employed as a feature selection tool for dimensionality reduction in order to further improve the diagnostic accuracy of the ELM classifier. The impact of the type of activation functions, the number of hidden neurons and the size of the feature subsets on the performance of ELM have been investigated in detail. The effectiveness of the proposed method has been rigorously evaluated against the ES disease dataset, a benchmark dataset, from UCI machine learning database in terms of classification accuracy. Experimental results have demonstrated that our method has achieved the best classification accuracy of 98.89% and an average accuracy of 98.55% via 10-fold cross-validation technique. The proposed method might serve as a new candidate of powerful methods for diagnosing ES diseases.  相似文献   

3.
This paper proposes a classifier named ensemble of polyharmonic extreme learning machine, whose part weights are randomly assigned, and it is harmonic between the feedforward neural network and polynomial. The proposed classifier provides a method for human face recognition integrating fast discrete curvelet transform (FDCT) with 2-dimension principal component analysis (2DPCA). FDCT is taken to be a feature extractor to obtain facial features, and then these features are dimensionality reduced by 2DPCA to decrease the computational complexity before they are input to the classifier. Comparison experiments of the proposed method with some other state-of-the-art approaches for human face recognition have been carried out on five well-known face databases, and the experimental results show that the proposed method can achieve higher recognition rate.  相似文献   

4.
5.
张志禹  刘思媛 《计算机科学》2018,45(10):267-271, 305
相比于传统的降维算法,深度学习中的栈式自编码器(Stacked Autoencoder,SAE)能够有效地学习特征并实现高效降维,然而对输入特征极其敏感。第二代离散曲波变换(Discrete Curvelet Transform,DCT)能够提取出人脸的各向信息(包含边缘和概貌特征),确保SAE的输入特征充分,从而弥补了其不足。因此,提出了一种基于Curv-SAE特征融合的人脸识别降维算法,即对人脸图像进行DCT得到特征脸并将其作为SAE的输入特征进行训练,特征融合后将其输入到分类器中进行识别。在ORL和FERET人脸数据库上的实验表明,与小波变换相比,曲波的特征信息更丰富;与传统的降维算法相比,SAE的特征表达更充分且识别精度更高。  相似文献   

6.
针对现有恶意软件分类方法融合的静态特征维度高、特征提取耗时、Boosting算法对大量高维特征样本串行训练时间长的问题,提出一种基于静态特征融合的分类方法。提取原文件和其反编译的Lst文件的灰度图像素特征、原文件的结构特征和Lst文件的内容特征,对特征融合和分类。在训练集采样时启用GOSS算法减少对训练样本的采样,使用LightGBM作为分类器,该分类器通过EFB对互斥特征降维。实验证明在三类特征融合下分类准确率达到了97.04%,通过启用GOSS采样减少了29%的训练时间,在分类效果上,融合的特征优于融合Opcode n-gram的特征,LightGBM优于传统深度学习和机器学习算法。  相似文献   

7.
Fingerprint matching based on extreme learning machine   总被引:2,自引:2,他引:0  
Considering fingerprint matching as a classification problem, the extreme learning machine (ELM) is a powerful classifier for assigning inputs to their corresponding classes, which offers better generalization performance, much faster learning speed, and minimal human intervention, and is therefore able to overcome the disadvantages of other gradient-based, standard optimization-based, and least squares-based learning techniques, such as high computational complexity, difficult parameter tuning, and so on. This paper proposes a novel fingerprint recognition system by first applying the ELM and Regularized ELM (R-ELM) to fingerprint matching to overcome the demerits of traditional learning methods. The proposed method includes the following steps: effective preprocessing, extraction of invariant moment features, and PCA for feature selection. Finally, ELM and R-ELM are used for fingerprint matching. Experimental results show that the proposed methods have a higher matching accuracy and are less time-consuming; thus, they are suitable for real-time processing. Other comparative studies involving traditional methods also show that the proposed methods with ELM and R-ELM outperform the traditional ones.  相似文献   

8.
纺织品缺陷分类是利用计算机视觉技术检测纺织品品质的一个关键环节。提出了一种基于小波框架的纺织品缺陷分类新方法。该方法使用纺织品图像的小波框架来描述缺陷的纹理特征。在最小分类误差训练框架下,通过联合设计一个基于线性变换矩阵的特征提取器和一个分类器,来获取面向缺陷分类的小波框架特征,并最小化分类器的错误概率。该方法对包含9类纺织品缺陷的329个样本,以及328个无缺陷样本进行了分类实验评估,获得了931%的分类准确率,相比传统的基于小波变换的分类方法提高了272%。  相似文献   

9.
This paper proposes a supervised multiscale Bayesian texture classifier. The classifier exploits the dual-tree complex wavelet transform (DT-CWT) to obtain complex-valued multiscale representations of training texture samples for each texture class. The high-pass subbands of DT-CWT decomposition of a texture image are used to form a multiscale feature vector representing magnitude and phase features. For computational efficiency, the dimensionality of feature vectors is reduced using principal component analysis (PCA). The class conditional probability density function of low-dimensional feature vectors for each texture class is then estimated by using Parzen-window estimate with identical Gaussian kernels and is used to represent the texture class. A query texture image is classified as the corresponding texture class with the highest a posteriori probability according to a Bayesian inferencing. The superior performance and robustness of the proposed classifier is demonstrated for classifying texture images from image databases. The proposed multiscale texture feature vector extracted from both magnitude and phase of DT-CWT subbands of a query image is also shown to be effective for texture retrieval.  相似文献   

10.
Textures and patterns are the distinguishing characteristics of objects. Texture classification plays fundamental role in computer vision and image processing applications. In this paper, texture classification using PDE (partial differential equation) approach and wavelet transform is presented. The proposed method uses wavelet transform to obtain the directional information of the image. A PDE for anisotropic diffusion is employed to obtain texture component of the image. The feature set is obtained by computing different statistical features from the texture component. The linear discriminant analysis (LDA) enhances separability of texture feature classes. The features obtained from LDA are class representatives. The proposed approach is experimented on three gray scale texture datasets: VisTex, Kylberg, and Oulu. The classification accuracy of the proposed method is evaluated using k-NN classifier. The experimental results show the effectiveness of the proposed method as compared to the other methods in the literature.  相似文献   

11.
In this paper, a novel recognition algorithm based on discriminant tensor subspace analysis (DTSA) and extreme learning machine (ELM) is introduced. DTSA treats a gray facial image as a second order tensor and adopts two-sided transformations to reduce dimensionality. One of the many advantages of DTSA is its ability to preserve the spatial structure information of the images. In order to deal with micro-expression video clips, we extend DTSA to a high-order tensor. Discriminative features are generated using DTSA to further enhance the classification performance of ELM classifier. Another notable contribution of the proposed method includes significant improvements in face and micro-expression recognition accuracy. The experimental results on the ORL, Yale, YaleB facial databases and CASME micro-expression database show the effectiveness of the proposed method.  相似文献   

12.
目前纹理图像分类有不同的方法,但对纹理的描述还不够全面,而且当有新方法提取的特征加入时,系统的可扩展性也不够,通用性不好。本文针对上述问题提出了一种将D-S证据理论与极限学习机相结合的决策级融合模型,用来对纹理图像进行分类。采用三种不同方法来提取特征以获得更多更全面的纹理表现形式,并对提取的每种特征向量用极限学习机建立相应的分类器,最后用D-S证据理论在不确定性表示、度量和组合方面有着的优势来进行决策级融合。对于证据理论中基本概率赋值函数(BPAF)难以有效获取的问题,由于极限学习机具有学习速度快,泛化性能好的优点并且产生唯一的最优解的优点,所以利用其来构造其基本概率赋值函数。实验结果表明这种方法比单个分类器具有更高的识别正确率,降低了识别的不确定性。  相似文献   

13.
Smartphones have different kinds of applications that help to promote health and care of humans. This paper proposes a practical and low-cost method for predicting air pollution which is applicable to the smartphones based on an image taken by their camera. To find the best method, in the first approach, some convenionalconventional feature extraction methods including wavelet transform, scale-invariant feature transform and histogram of oriented gradients are implemented. Then, to reduce the dimension of the extracted feature vectors, principal component analysis is employed. For classification of the obtained reduced feature vectors, multilayer perceptron is employed. In the second approach, the performance of convolutional neural network (CNN) in classifying the sky images in terms of air quality is investigated. In CNN, the fully connected classifier can be replaced by other classifiers such as extreme learning machine (ELM). The results illustrate that if the deep features obtained by CNN are fed to the ELM, an accuracy of 66.92% in predicting the level of air quality is achieved, which is higher than the results of other previous and conventional methods.  相似文献   

14.
高光谱图像的高维特性和波段间的高相关性,导致高光谱图像地物识别问题研究中,面临着数据量大、信息冗余的问题,降低了高光谱图像的分类识别精度。针对以上问题,提出了基于局部保留降维(Local Fisher Discriminant Analysis,LFDA)结合遗传算法(Genetic Algorithm, GA )优化极限学习机(Extreme Learning Machine, ELM)的高光谱图像分类方法。首先,采用LFDA对高光谱图像数据进行降维处理,消除信息冗余并保留局部邻域内主要特征;然后用GA优化ELM,对降维处理后的特征样本进行分类,提高高光谱图像的分类识别精度。将该方法应用于Salinas和Pavia University高光谱图像的地物识别问题研究,分类精度分别达到了98.56%和97.11%,由此验证了该方法的有效性。  相似文献   

15.
提出了一种新的纹理分类的方法,该方法把基于无抽样小波变换的特征提取器和基于欧几里得距离的分类器进行了合并。把方差、偏态系数、峰态系数、三者的联合及谱直方图作为描述纹理图像不相重叠的图像窗的特征。一个使用线性转换矩阵的特征提取器对分类导向的特征做进一步的提取。利用基于欧几里得距离的分类器,每个纹理图像不相重叠的图像窗被确定到属于它的那一类。基于最小分类错误训练方法的特征提取器和分类器设计的合并使分类错误达到了最小化。使用该方法对25类BrodTex纹理图像进行了评估,分类精确度达到90%以上。  相似文献   

16.
王鑫  李可  徐明君  宁晨 《计算机应用》2019,39(2):382-387
针对传统的基于深度学习的遥感图像分类算法未能有效融合多种深度学习特征,且分类器性能欠佳的问题,提出一种改进的基于深度学习的高分辨率遥感图像分类算法。首先,设计并搭建一个七层卷积神经网络;其次,将高分辨率遥感图像样本输入到该网络中进行网络训练,得到最后两个全连接层输出作为遥感图像两种不同的高层特征;再次,针对该网络第五层池化层输出,采用主成分分析(PCA)进行降维,作为遥感图像的第三种高层特征;然后,将上述三种高层特征通过串联的形式进行融合,得到一种有效的基于深度学习的遥感图像特征;最后,设计了一种基于逻辑回归的遥感图像分类器,可以对遥感图像进行有效分类。与传统基于深度学习的遥感图像分类算法相比,所提算法分类准确率有较高提升。实验结果表明,该算法在分类准确率、误分类率和Kappa系数上表现优异,能实现良好的分类效果。  相似文献   

17.
目前多数图像分类的方法是采用监督学习或者半监督学习对图像进行降维,然而监督学习与半监督学习需要图像携带标签信息。针对无标签图像的降维及分类问题,提出采用混阶栈式稀疏自编码器对图像进行无监督降维来实现图像的分类学习。首先,构建一个具有三个隐藏层的串行栈式自编码器网络,对栈式自编码器的每一个隐藏层单独训练,将前一个隐藏层的输出作为后一个隐藏层的输入,对图像数据进行特征提取并实现对数据的降维。其次,将训练好的栈式自编码器的第一个隐藏层和第二个隐藏层的特征进行拼接融合,形成一个包含混阶特征的矩阵。最后,使用支持向量机对降维后的图像特征进行分类,并进行精度评价。在公开的四个图像数据集上将所提方法与七个对比算法进行对比实验,实验结果表明,所提方法能够对无标签图像进行特征提取,实现图像分类学习,减少分类时间,提高图像的分类精度。  相似文献   

18.
针对处理高维度属性的大数据的属性约减方法进行了研究。发现属性选择和子空间学习是属性约简的两种常见方法,其中属性选择具有很好的解释性,子空间学习的分类效果优于属性选择。而往往这两种方法是各自独立进行应用。为此,提出了综合这两种属性约简方法,设计出新的属性选择方法。即利用子空间学习的两种技术(即线性判别分析(LDA)和局部保持投影(LPP)),考虑数据的全局特性和局部特性,同时设置稀疏正则化因子实现属性选择。基于分类准确率、方差和变异系数等评价指标的实验结果比较,表明该算法相比其它对比算法,能更有效的选取判别属性,并能取得很好的分类效果。  相似文献   

19.
极端学习机以其快速高效和良好的泛化能力在模式识别领域得到了广泛应用,然而现有的ELM及其改进算法并没有充分考虑到数据维数对ELM分类性能和泛化能力的影响,当数据维数过高时包含的冗余属性及噪音点势必降低ELM的泛化能力,针对这一问题本文提出一种基于流形学习的极端学习机,该算法结合维数约减技术有效消除数据冗余属性及噪声对ELM分类性能的影响,为验证所提方法的有效性,实验使用普遍应用的图像数据,实验结果表明本文所提算法能够显著提高ELM的泛化性能。  相似文献   

20.
In machine learning the so-called curse of dimensionality, pertinent to many classification algorithms, denotes the drastic increase in computational complexity and classification error with data having a great number of dimensions. In this context, feature selection techniques try to reduce dimensionality finding a new more compact representation of instances selecting the most informative features and removing redundant, irrelevant, and/or noisy features. In this paper, we propose a filter-based feature selection method for working in the multiple-instance learning scenario called ReliefF-MI; it is based on the principles of the well-known ReliefF algorithm. Different extensions are designed and implemented and their performance checked in multiple instance learning. ReliefF-MI is applied as a pre-processing step that is completely independent from the multi-instance classifier learning process and therefore is more efficient and generic than wrapper approaches proposed in this area. Experimental results on five benchmark real-world data sets and 17 classification algorithms confirm the utility and efficiency of this method, both statistically and from the point of view of execution time.  相似文献   

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