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1.
This paper proposes a novel and real-time classifiers combination approach, group decision-making combination (GDC) approach, which can dynamically select the classifiers and perform linear combination. We also prove that the orthogonal wavelet transform can be regarded as an effective image's preprocessing tool adapted to classifiers combination. GDC has been successfully used for face recognition, which can improve on the recognition rate for the algebraic features. Experiment results also show that it is superior to the conventional combination method, majority voting method.  相似文献   

2.
Robust CDMA multiuser detection using a neural-network approach   总被引:1,自引:0,他引:1  
Abstract-Recently, a robust version of the linear decorrelating detector (LDD) based on the Huber's M-estimation technique has been proposed. In this paper, we first demonstrate the use of a three-layer recurrent neural network (RNN) to implement the LDD without requiring matrix inversion. The key idea is based on minimizing an appropriate computational energy function iteratively. Second, it will be shown that the M-decorrelating detector (MDD) can be implemented by simply incorporating sigmoidal neurons in the first layer of the RNN. A proof of the redundancy of the matrix inversion process is provided and the computational saving in realistic network is highlighted. Third, we illustrate how further performance gain could be achieved for the subspace-based blind MDD by using robust estimates of the signal subspace components in the initial stage. The impulsive noise is modeled using non-Gaussian alpha-stable distributions, which do not include a Gaussian component but facilitate the use of the recently proposed geometric signal-to-noise ratio (G-SNR). The characteristics and performance of the proposed neural-network detectors are investigated by computer simulation.  相似文献   

3.
针对人体活动识别,现有的研究更多关注于传感器之间的融合,较少将研究方向转移到三轴加速度计等传感器内轴之间的相关性方面。为有效利用轴之间的相关性,提出一种基于数据融合的卷积神经网络方法。借助利用轴之间的相关性的单通道数据融合方法得到融合数据,将融合数据输入到卷积神经网络中提取特征。在WISDM数据集上的实验结果表明,该方法的准确率达到了98.80%,优于不使用数据融合的卷积神经网络方法。  相似文献   

4.
Eigenpaxels and a neural-network approach to image classification   总被引:1,自引:0,他引:1  
A expansion encoding approach to image classification is presented. Localized principal components or "eigenpaxels" are used as a set of basis functions to represent images. That is, principal-component analysis is applied locally rather than on the entire image. The "eigenpaxels" are statistically determined using a database of the images of interest. Classification based on visual similarity is achieved through the use of a single-layer error-correcting neural network. Expansion encoding and the technique of subsampling are key elements in the processing stages of the eigenpaxel algorithm. Tested using a database of frontal face images consisting of 40 individuals, the algorithm exhibits equivalent performance to other comparable but more cumbersome methods. In addition, the technique is shown to be robust to various types of image noise.  相似文献   

5.
Multimedia Tools and Applications - In order to accurately track and recognize faces in video moving images, a method for tracking and recognizing faces in video moving images based on...  相似文献   

6.
This paper uses principal component analysis(PCA) to train the face and extract the characteristic value. This approach achieves the purpose of rapid attendance. PCA is an early and important approach for face recognization. It can reduce the dimension of face image space as well as describe the variation characteristics between different face images. The attendance system is a realtime system that requires shorter response time, for which PCA is a best choice. We use histogram equalization to eliminate the noise and improve the performance. With convenient MATLAB GUI visual operation interface, users can click on the corresponding button to implement face recognition tasks.  相似文献   

7.
Two-dimensional (2D) discrimination analysis using methods such as 2D PCA and Image LDA is of interest in face recognition because it extracts discriminative features faster than one-dimensional (1D) discrimination analysis. However, existing 2D methods generally use more discriminative features and take longer to test than 1D methods. 2D PCA in particular cannot make full use of the Fisher discriminant criterion. Image LDA also has drawbacks in that it cannot perform 2D principal component analysis and discards components with poor discriminative capabilities. In addition, existing 2D methods cannot provide an automatic strategy to choose 2D principal components or discriminant vectors. In this paper, we propose 2D Fisherface, a novel discrimination approach that combines the two-stage “PCA+LDA” strategy and 2D discrimination techniques. It can extract face discriminative features by automatically selecting two-dimensional principal components and discriminant vectors. Using the AR database as the test data, it is shown that the proposed approach is faster and more effective than several representative 1D and 2D discrimination methods.  相似文献   

8.
为有效解决小样本问题 ,从线性子空间的角度出发 ,构造了一种矩阵变换 ,得到了类内散布矩阵的另一个对称线性子空间 ;通过对两个子空间的分别求解 ,从而得到样本有效的鉴别信息。该方法有效地解决了传统 Fisher鉴别分析方法中的最终特征维数受类别数限制的问题。在 NUST603和 ORL人脸数据库上的实验结果验证了算法的有效性。  相似文献   

9.
Multimedia Tools and Applications - Recognition of an object from an image or image sequences is an important task in computer vision. It is an important low-level image processing operation and...  相似文献   

10.
Face recognition is challenging because variations can be introduced to the pattern of a face by varying pose, lighting, scale, and expression. A new face recognition approach using rank correlation of Gabor-filtered images is presented. Using this technique, Gabor filters of different sizes and orientations are applied on images before using rank correlation for matching the face representation. The representation used for each face is computed from the Gabor-filtered images and the original image. Although training requires a fairly substantial length of time, the computation time required for recognition is very short. Recognition rates ranging between 83.5% and 96% are obtained using the AT&T (formerly ORL) database using different permutations of 5 and 9 training images per subject. In addition, the effect of pose variation on the recognition system is systematically determined using images from the UMIST database.  相似文献   

11.
针对传统Gabor滤波器组在人脸识别过程中特征提取时间长、计算量大的问题,提出一种利用局部Gabor滤波器组进行人脸图像中频特征提取的方法.选择中频带的Gabor滤波器构造局部中频Gabor滤波器组;提取局部Gabor中频特征;采用线性判别分析法(linear discriminate analysis,LDA)进一步提取Fisher特征,得到图像的Gabor+ Fisher特征,利用最近邻法进行人脸图像识别.基于ORL和AR人脸库的实验结果表明,基于此局部Gabor滤波器组的人脸识别方法较传统的Gabor特征提取方法降低了40%的特征维数,加快了特征提取速度,提高了人脸识别率.  相似文献   

12.
A time-series approach has been employed to devise neural-network topologies for time dependent partial discharge pulse pattern recognition applications. The cascaded output neural-network structure was found to provide the highest success rate in differentiating between two different partial discharge patterns. This was accomplished by utilizing the indexed feature of the first stage output as one of the inputs into the second stage of the cascaded neural network.  相似文献   

13.
In this paper we propose a multiobjective decision making based neural-network model and algorithm for image reconstruction from projections. This model combines the Hopfield's model and multiobjective decision making approach. We develop a weighted sum optimization based neural-network algorithm. The dynamical process of the net is based on minimization of a weighted sum energy function and Euler's iteration, and apply this algorithm to image reconstruction from computer-generated noisy projections and Siemens Somatson DR scanner data, respectively. Reconstructions based on this method is shown to be superior to conventional iterative reconstruction algorithms such as the multiplicate algebraic reconstruction technique (MART) and convolution from the point of view of accuracy of reconstruction. Computer simulation using the multiobjective method shows a significant improvement in image quality and convergence behavior over the conventional algorithms  相似文献   

14.
It is generally assumed when using Bayesian inference methods for neural networks that the input data contains no noise or corruption. For real-world (errors in variable) problems this is clearly an unsafe assumption. This paper presents a Bayesian neural-network framework which allows for input noise provided that some model of the noise process exists. In the limit where the noise process is small and symmetric it is shown, using the Laplace approximation, that this method gives an additional term to the usual Bayesian error bar which depends on the variance of the input noise process. Further, by treating the true (noiseless) input as a hidden variable and sampling this jointly with the network weights using a Markov chain Monte Carlo method, it is demonstrated that it is possible to infer the regression over the noiseless input.  相似文献   

15.
The ensemble approach to neural-network learning and generalization   总被引:2,自引:0,他引:2  
A method is suggested for learning and generalization with a general one-hidden layer feedforward neural network. This scheme encompasses the use of a linear combination of heterogeneous nodes having randomly prescribed parameter values. The learning of the parameters is realized through adaptive stochastic optimization using a generalization data set. The learning of the linear coefficients in the linear combination of nodes is achieved with a linear regression method using data from the training set. One node is learned at a time. The method allows for choosing the proper number of net nodes, and is computationally efficient. The method was tested on mathematical examples and real problems from materials science and technology.  相似文献   

16.
Face and gesture recognition: overview   总被引:5,自引:0,他引:5  
Computerised recognition of faces and facial expressions would be useful for human-computer interface, and provision for facial animation is to be included in the ISO standard MPEG-4 by 1999. This could also be used for face image compression. The technology could be used for personal identification, and would be proof against fraud. Degrees of difference between people are discussed, with particular regard to identical twins. A particularly good feature for personal identification is the texture of the iris. A problem is that there is more difference between images of the same face with, e.g., different expression or illumination, than there sometimes is between images of different faces. Face recognition by the brain is discussed  相似文献   

17.
Face recognition: features versus templates   总被引:22,自引:0,他引:22  
Two new algorithms for computer recognition of human faces, one based on the computation of a set of geometrical features, such as nose width and length, mouth position, and chin shape, and the second based on almost-gray-level template matching, are presented. The results obtained for the testing sets show about 90% correct recognition using geometrical features and perfect recognition using template matching  相似文献   

18.
卷积神经网络在检测不同尺度的人脸时所需要的计算量很大,检测过程由多个分离的步骤组成,过于复杂。针对这两方面的不足,提出一种多尺度卷积神经网络模型。根据卷积神经网络各个层具有大小不同的感受野,从不同层提取多个尺度的特征向量分别进行人脸分类与回归,并将网络的全连接层改成卷积层,以适应不同大小的图片输入。该方法将人脸检测的多个步骤集成到一个卷积神经网络中,降低了模型复杂度。实验结果表明,相同测试条件下,所提方法相比其他人脸检测模型在准确率和检测速度上均有显著提升。  相似文献   

19.
由于光照、遮挡、尺度变化等原因,在真实多变场景下完成人脸追踪面临挑战。探究了基于卷积神经网络(CNN)的人脸追踪,将基本的卷积神经网络改进为孪生神经网络,在OTB数据集上采用端到端的方式,以成对图像区域作为输入,输出两者距离,通过距离评估图像区域相似性;加入边框回归算法(bounding box regression)微调追踪结果。实验结果表明,改进后的神经网络优于传统的卷积神经网络,能达到更好的人脸追踪效果。  相似文献   

20.
人脸图像的易取性和人脸变化的多样性使人脸识别研究更富有挑战性.按照人脸检测、特征提取和识别3个关键过程,分别对基于二维和三维人脸信息的人脸识别技术和方法进行了详细的阐述;展望了人脸识别研究的趋势,并提出了可能取得突破性研究进展的研究途径.  相似文献   

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