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1.
The eigenface method that uses principal component analysis (PCA) has been the standard and popular method used in face recognition. This paper presents a PCA - memetic algorithm (PCA-MA) approach for feature selection. PCA has been extended by MAs where the former was used for feature extraction/dimensionality reduction and the latter exploited for feature selection. Simulations were performed over ORL and YaleB face databases using Euclidean norm as the classifier. It was found that as far as the recognition rate is concerned, PCA-MA completely outperforms the eigenface method. We compared the performance of PCA extended with genetic algorithm (PCA-GA) with our proposed PCA-MA method. The results also clearly established the supremacy of the PCA-MA method over the PCA-GA method. We further extended linear discriminant analysis (LDA) and kernel principal component analysis (KPCA) approaches with the MA and observed significant improvement in recognition rate with fewer features. This paper also compares the performance of PCA-MA, LDA-MA and KPCA-MA approaches.  相似文献   

2.
改进的人脸识别主分量分析算法   总被引:3,自引:0,他引:3  
在应用于人脸识别领域的主分量分析(PCA)算法中,为了降低与外界光照变化相关的特征向量对提取特征的影响,提出了一种改进的主分量分析(MPCA)算法,利用相对应的标准方差对提取的特征矢量元素进行归一化处理.采用耶鲁大学的2个人脸数据库(Yale face database和Yaleface database B)进行了验证,实验结果表明,对于正面人脸和具有小角度姿态变化情况下的人脸,提出方法的性能优于传统的PCA和LDA(线性判别分析)算法,而运算量和PCA算法相同,大大低于LDA算法.  相似文献   

3.
二维最大散度差线性鉴别分析方法不仅有效地避免了在人脸识别中传统的Fisher线性鉴别分析通常存在的“小样本问题”,而且使其特征抽取的速度有了大幅度的提高.本文通过引入著名的“核技巧”,将二维最大散度差线性鉴别分析扩展到非线性空间,提出了一种新的二维核最大散度差鉴别分析方法.该方法不仅抽取了图像中更加有效的非线性鉴别特征,使正确识别率显著提高,而且为二维非线性鉴别分析提供了一个统一的构架.最后在AR标准人脸库中的实验结果验证了本文算法的有效性.  相似文献   

4.
二维最大散度差鉴别准则和二维Fisher鉴别准则抽取的特征具有很强的相关性.本文在此基础上,通过对传统的基于向量的典型相关分析方法进行分析改进,提出了一种新的直接基于图像二维鉴别特征矩阵融合的二维典型相关分析方法,并将其应用于人脸识别的特征融合过程中.较基于向量的典型相关分析,该方法计算过程中构造的协方差矩阵维数大幅度减小.这在一定程度上避免了人脸识别中存在的"高维小样本问题",另一方面也使算法的速度明显提高.  相似文献   

5.
为了提高人脸识别率,研究了一种基于边缘二值图像特征向量提取的方法。通过局部二值模式提取特征向量,考虑到边缘二值图像特征向量与局部二值模式提取的特征向量的区别,提出了将这两类特征向量通过PCA方法融合实现人脸识别的方法。实验结果表明基于两类特征向量融合的人脸识别方法可以有效地提高识别率。  相似文献   

6.
A kernel-based discriminant analysis method called kernel direct discriminant analysis is employed, which combines the merit of direct linear discriminant analysis with that of kernel trick. In order to demonstrate its better robustness to the complex and nonlinear variations of real face images , such as illumination, facial expression, scale and pose variations, experiments are carried out on the Olivetti Research Laboratory, Yale and self-built face databases. The results indicate that in contrast to kernel principal component analysis and kernel linear discriminant analysis, the method can achieve lower (7%) error rate using only a very small set of features. Furthermore, a new corrected kernel model is proposed to improve the recognition performance. Experimental results confirm its superiority (1% in terms of recognition rate) to other polynomial kernel models.  相似文献   

7.
将基于多个嵌入图组合形式的半监督判别分析(SDA)以及核SDA(KSDA)应用于全监督的语音情感识别.在语音信号样本情感成分的预处理阶段,从样本语段中提取出多种特征及其统计参数,包括基音、过零率、能量、持续长度、共振峰和MFCC(Mel频率倒谱系数).在将样本特征送入分类器之前的维数约简阶段,使用经过参数优化的SDA或KSDA进行降维.Berlin语音情感数据库上的实验表明,在使用多类SVM分类器时的全监督语音情感识别中,SDA优于其他一些先进的基于谱图学习的维数约简算法,如LDA,LPP,MFA等,而KSDA通过核化的数据映射,能够取得比上述所有算法更好的识别效果.  相似文献   

8.
人脸识别是计算机视觉和模式识别领域的一个活跃课题,有着十分广泛的应用前景。给出了一种基于PCA和LDA方法的人脸识别系统的实现。首先该算法采用奇异值分解技术提取主成分,然后用F isher线性判别分析技术来提取最终特征,最后将测试图像的投影与每一训练图像的投影相比较,与测试图像最接近的训练图像被系统识别出,图像的比较采用了欧几里德距离,仿真结果表明了该方法的有效性。  相似文献   

9.
为了提高图像检索系统的精度,提出了一种基于多种异质特征的新颖哈希函数学习方法.该方法首先利用特征空间中相似样本与非相似样本分布的不平衡性来提升每个弱分类器的性能,从而建立非对称的Boosting框架;然后将一种基于异质特征子空间学习的线性判别弱分类器融入该框架下,并利用每轮算法中的误判样本的信息来依次学习紧致且平衡的哈希编码.该方法能有效地融合具有互补功能的不同模态的信息,实现了检索系统的性能提升.在2个公开数据集上的实验结果表明该方法优于其他算法,由此看出增加多源异质特征和利用不平衡性学习紧致哈希编码都可以大大提高图像检索的精度.  相似文献   

10.
所统计分析的数据集是前列腺癌基因数据集.采用分片逆回归方法和线性判别分析(LDA),二次判别分析(QDA).对基因芯片(微阵列)数据进行分析.用SIR降维,用LDA和QDA分类.讨论分片逆回归方法和二种方法对基因样本进行分类的效果.  相似文献   

11.
提出了一种新的基于核判别分析的手写汉字识别方法。核判别是对线性判别式分析的非线性判别分布的扩展。阐述了核判别分析法的基本原理,建立了核判别分析手写体识别模型,研究分析了核判别分析手写体识别模型的缺陷并提出了优化策略。在此基础上,采用C#与核判别分析相结合的算法,更好地展示了核判别算法的算法优势,采用高级语言提高了网络的学习训练速度和识别效果。  相似文献   

12.
提出了一种基于gamma分布的NMF算法(GNMF),并将之用于人脸特征抽取.构造了特征子空间,并在特征子空间内实现脸部识别.结果表明,GNMF算法可行且有效,以GNMF为基础的人脸识别率较高.  相似文献   

13.
14.
INTRODUCTION Recent techniques based on oligonucleotide or cDNA microarrays allow the expression level of thousands of genes to be monitored in parallel (Golub et al., 1999). A critically important factor for cancer diagnosis and treatment is the reliable prediction of tumor progression. A remarkable advance for mo- lecular biology and for cancer research is cDNA mi- croarray technology. cDNA microarray datasets havea high dimensionality corresponding to the large number of genes monit…  相似文献   

15.
Power Quality (PQ) combined disturbances become common along with ubiquity of voltage flickers and harmonics. This paper presents a novel approach to classify the different patterns of PQ combined disturbances. The classification system consists of two parts, namely the feature extraction and the automatic recognition. In the feature extraction stage, Phase Space Reconstruction (PSR), a time series analysis tool, is utilized to construct disturbance signal trajectories. For these trajectories, several indices are proposed to form the feature vectors. Support Vector Machines (SVMs) are then implemented to recognize the different patterns and to evaluate the efficiencies. The types of disturbances discussed include a combination of short-term disturbances (voltage sags, swells) and long-term disturbances (flickers, harmonics), as well as their homologous single ones. The feasibilities of the proposed approach are verified by simulation with thousands of PQ events. Comparison studies based on Wavelet Transform (WT) and Artificial Neural Network (ANN) are also reported to show its advantages.  相似文献   

16.
面向动画创作的三维人脸表情动画生成框架由人脸模型简化、特征点驱动以及表情动画生成等三部分组成。以MPEG-4人脸动画定义标准为基础,提出了以脸部定义参数流驱动关键特征点的动画生成算法。实验结果表明:该方法实现了真实感和实时性的有效结合,能满足动画创作的要求。  相似文献   

17.
改进传统的活动形状模型法,准确地提取人脸特征点后,利用人脸特征点初步估计人脸姿态,以初步估计值为初始值,通过线性回归迭代算法,精确估计3D人脸空间姿态。实验结果表明,本文提出的新方法不仅可以获得稳定和唯一的3D人脸空间姿态.而且与同类方法比较具有较好的姿态估计精确度。  相似文献   

18.
A new customization approach based on support vector regression (SVR) is proposed to obtain individual headrelated
impulse response (HRIR) without complex measurement and special equipment. Principal component analysis (PCA) is
first applied to obtain a few principal components and corresponding weight vectors correlated with individual anthropometric
parameters. Then the weight vectors act as output of the nonlinear regression model. Some measured anthropometric
parameters are selected as input of the model according to the correlation coefficients between the parameters and the weight
vectors. After the regression model is learned from the training data, the individual HRIR can be predicted based on the
measured anthropometric parameters. Compared with a back-propagation neural network (BPNN) for nonlinear regression,
better generalization and prediction performance for small training samples can be obtained using the proposed PCA-SVR
algorithm.  相似文献   

19.
A two-layer method based on support vector machines (SVMs) has been developed to distinguish epoxide hydrolases (EHs) from other enzymes and to classify its subfamilies using its primary protein sequences. SVM classifiers were built using three different feature vectors extracted from the primary sequence of EHs: the amino acid composition (AAC), the dipeptide composition (DPC), and the pseudo-amino acid composition (PAAC). Validated by 5-fold cross tests, the first layer SVM classifter can differentiate EHs and non-EHs with an accuracy of 94.2% and has a Matthew's correlation coefficient (MCC) of 0.84. Using 2-fold cross validation, PAAC-based second layer SVM can further classify EH subfamilies with an overall accuracy of 90.7% and MCC of 0.87 as compared to AAC (80.0%) and DPC (84.9%). A program called EHPred has also been developed to assist readers to recognize EHs and to classify their subfamilies using primary protein sequences with greater accuracy.  相似文献   

20.
本文采用基于递归算法的去除离散点法消除孤立噪声,选用扫描边界的方法分割字符,来研究验证码自动识别技术,选择和提取稳定而又便于表示的特征向量是本系统的核心之一。本文提出了简单的字符特征提取方法:采用网格灰度特征并对该特征进行线性鉴别分析(LDA,Linear discrimlnant analysis)变换,结合最小距离分类器完成字符识别过程,通过提高训练样本数,有效解决了形近字符识别率低的问题,取得了很好的识别效果。  相似文献   

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