基于脑电信号的情感识别研究

针对如何提高脑电信号情感识别的正确率这一问题,在得到的原始脑电信号进行分频带特征提取后,一方面采用支持向量机、K近邻算法、朴素贝叶斯和神经网络算法对小波熵、近似熵、功率谱密度、微分熵,进行训练和分类学习;另一方面,基于四种不同的电极放置方式,对微分熵特征采用支持向量机和经遗传算法参数寻优的支持向量机算法进行训练。结果显示,在12通道条件下能够得到91.99%的总体准确率,最高情感识别准确率已经达到97.59%。研究结果表明,减少电极可以获得较高的情感识别分类结果,并且采用参数寻优后的支持向量机算法能够有效提升准确率。     

Classification of defects in steel strip surface based on multiclass support vector machine

In this paper, we use support vector machine to classify the defects in steel strip surface images. After image binarization, three types of image features, including geometric feature, grayscale feature and shape feature, are extracted by combining the defect target image and its corresponding binary image. For the classification model based on support vector machine, we utilize Gauss radial basis as the kernel function, determine model parameters by cross-validation and employ one-versus-one method for multiclass classifier. Experiment results show that support vector machine model outperforms the traditional classification model based on back-propagation neural network in average classification accuracy.     

Modular neural-SVM scheme for speech emotion recognition using ANOVA feature selection method

The speech signal consists of linguistic information and also paralinguistic one such as emotion. The modern automatic speech recognition systems have achieved high performance in neutral style speech recognition, but they cannot maintain their high recognition rate for spontaneous speech. So, emotion recognition is an important step toward emotional speech recognition. The accuracy of an emotion recognition system is dependent on different factors such as the type and number of emotional states and selected features, and also the type of classifier. In this paper, a modular neural-support vector machine (SVM) classifier is proposed, and its performance in emotion recognition is compared to Gaussian mixture model, multi-layer perceptron neural network, and C5.0-based classifiers. The most efficient features are also selected by using the analysis of variations method. It is noted that the proposed modular scheme is achieved through a comparative study of different features and characteristics of an individual emotional state with the aim of improving the recognition performance. Empirical results show that even by discarding 22% of features, the average emotion recognition accuracy can be improved by 2.2%. Also, the proposed modular neural-SVM classifier improves the recognition accuracy at least by 8% as compared to the simulated monolithic classifiers.     

基于SAE和GNDO-SVM的脑电信号情绪识别

情感计算是现代人机交互中的关键问题, 随着人工智能的发展, 基于脑电信号(electroencephalogram, EEG)的情绪识别已经成为重要的研究方向. 为了提高情绪识别的分类精度, 本研究引入堆叠自动编码器(stacked auto-encoder, SAE)对EEG多通道信号进行深度特征提取, 并提出一种基于广义正态分布优化的支持向量机(generalized normal distribution optimization based support vector machine, GNDO-SVM)情绪识别模型. 实验结果表明, 与基于遗传算法、粒子群算法和麻雀搜索算法优化的支持向量机模型相比, 所提出的GNDO-SVM模型具有更优的分类性能, 基于SAE深度特征的情感识别准确率达到了90.94%, 表明SAE能够有效地挖掘EEG信号不同通道间的深度相关性信息. 因此, 利用SAE深度特征结合GNDO-SVM模型可以有效地实现EEG信号的情绪识别.     

疲劳驾驶面部表情识别算法

针对疲劳驾驶的六种表情 ,提出几何规范化结合 Gabor滤波提取表情特征 ,使用支持向量机对疲劳驾驶的面部表情分类识别的系统。首先对视频图像预处理进行几何规范化 ,利用二维 Gabor核函数构造最优滤波器 48个,获取 48个面部表情特征点 ,最后利用支持向量机进行面部表情分类识别。实验结果表明径向基函数的 SVM性能最好。     

Facial expression recognition based on local region specific features and support vector machines

Facial expressions are one of the most powerful, natural and immediate means for human being to communicate their emotions and intensions. Recognition of facial expression has many applications including human-computer interaction, cognitive science, human emotion analysis, personality development etc. In this paper, we propose a new method for the recognition of facial expressions from single image frame that uses combination of appearance and geometric features with support vector machines classification. In general, appearance features for the recognition of facial expressions are computed by dividing face region into regular grid (holistic representation). But, in this paper we extracted region specific appearance features by dividing the whole face region into domain specific local regions. Geometric features are also extracted from corresponding domain specific regions. In addition, important local regions are determined by using incremental search approach which results in the reduction of feature dimension and improvement in recognition accuracy. The results of facial expressions recognition using features from domain specific regions are also compared with the results obtained using holistic representation. The performance of the proposed facial expression recognition system has been validated on publicly available extended Cohn-Kanade (CK+) facial expression data sets.     

Recognition of control chart patterns using an intelligent technique

Control chart patterns (CCPs) are important statistical process control tools for determining whether a process is run in its intended mode or in the presence of unnatural patterns. Automatic recognition of abnormal patterns in control charts has seen increasing demands nowadays in the manufacturing processes. This paper presents a novel hybrid intelligent method for recognition of common types of CCP. The proposed method includes three main modules: the feature extraction module, the classifier module and optimization module. In the feature extraction module, a proper set of the shape features and statistical features is proposed as the efficient characteristic of the patterns. In the classifier module multilayer perceptron neural network and support vector machine (SVM) are investigated. In support vector machine training, the hyper-parameters have very important roles for its recognition accuracy. Therefore, in the optimization module, improved bees algorithm is proposed for selecting of appropriate parameters of the classifier. Simulation results show that the proposed algorithm has very high recognition accuracy.     

基于音乐情感识别的舞台灯光控制方法研究

为了实现音乐情感识别的舞台灯光自动控制,需对音乐文件进行情感标记。针对人工情感标记效率低、速度慢的问题,开展了基于音乐情感识别的舞台灯光控制方法研究,提出了一种基于支持向量机和粒子群优化的音乐情感特征提取、分类和识别算法。首先以231首MIDI音乐文件为例,对平均音高、平均音强、旋律的方向等7种音乐基本特征进行提取并进行标准化处理;之后组成音乐情感特征向量输入支持向量机（SVM）多分类器,并利用改进的粒子群算法（PSO）优化分类器参数,建立标准音乐分类模型;最后设计灯光动作模型,将新的音乐文件通过离散情感模型与灯光动作相匹配,生成舞台灯光控制方法。实验结果表明了情感识别模型的有效性,与传统SVM多分类模型相比,明显提高了音乐情感的识别率,减少了测试时间,从而为舞台灯光设计人员提供合理参考。     

基于共同空间模式的情感脑电信号的空域特征提取

为了改善基于脑电(EEG)的情感分类性能,提高多分类情况下的识别准确率,提出 了一种基于共同空间模式(CSP)的空域滤波算法。首先使用传统的CSP 方法设计空域滤波器, 并通过该滤波器对3 种情感类型(即积极、中性和消极)的EEG 信号进行线性投影,以提取空域 特征。此外,考虑到传统近似联合对角化(JAD)算法是使用“得分最高的特征值”准则进行特征向 量的选择,该情况可能导致无法有效区分多分类的情感状态,因此针对最高分特征值位置存在 的所有可能情况设计了不同的特征值选择方法。对实验室自主采集数据集,使用支持向量模型 (SVM)作为分类器进行对比实验。结果表明基于CSP 的空域特征提取方法在三分类情感识别中 平均准确率达到了87.54%,证明其在情感识别应用中具有可行性。     

Class-specific multiple classifiers scheme to recognize emotions from speech signals

Automatic emotion recognition from speech signals is one of the important research areas, which adds value to machine intelligence. Pitch, duration, energy and Mel-frequency cepstral coefficients (MFCC) are the widely used features in the field of speech emotion recognition. A single classifier or a combination of classifiers is used to recognize emotions from the input features. The present work investigates the performance of the features of Autoregressive (AR) parameters, which include gain and reflection coefficients, in addition to the traditional linear prediction coefficients (LPC), to recognize emotions from speech signals. The classification performance of the features of AR parameters is studied using discriminant, k-nearest neighbor (KNN), Gaussian mixture model (GMM), back propagation artificial neural network (ANN) and support vector machine (SVM) classifiers and we find that the features of reflection coefficients recognize emotions better than the LPC. To improve the emotion recognition accuracy, we propose a class-specific multiple classifiers scheme, which is designed by multiple parallel classifiers, each of which is optimized to a class. Each classifier for an emotional class is built by a feature identified from a pool of features and a classifier identified from a pool of classifiers that optimize the recognition of the particular emotion. The outputs of the classifiers are combined by a decision level fusion technique. The experimental results show that the proposed scheme improves the emotion recognition accuracy. Further improvement in recognition accuracy is obtained when the scheme is built by including MFCC features in the pool of features.     

基于多级SVM分类的语音情感识别算法

为了提高语音情感识别系统的识别准确率,本文在传统支持向量机(SVM)方法的基础之上,提出了一种基于PCA的多级SVM情感分类算法。首先将容易区分的情感分开,针对混淆度大且不能再利用多级分类策略直接进行区分的情感,采用主成分分析法(PCA)进行特征降维,然后逐级地判断出输入语音所属的情感类型。与传统基于SVM分类算法的语音情感识别相比,本文提出的方法可将7种情感的平均识别率提高5.05%,并且特征维度可降低58.3%,从而证明了本文所提出的方法的正确性与有效性。     

面向数据增强的多种语音情感分类算法研究

目前语音情感识别存在语音样本不足、提取的特征数据量大和无关特征多使得识别率不高的问题。针对语音样本不足的情况,在预处理阶段提出了时频域的数据增强方法,对原有的数据库进行扩充;根据传统算法中提取的特征数据量大且与情感无关的特征多的现状,提取了1 582维的情感特征和10组低级描述特征。分别在支持向量机、随机森林和K最邻近3种机器学习算法上做了对比实验。实验证明:支持向量机的平均识别率比较好。在所提取的10组特征组中,LogMelFreqBand特征在3种算法上的精确度分别为74.63%、64.93%和66.42%;而pcm_fftMag_mfcc特征的精确度分别为84.33%、73.13%和58.21%。     

基于人脸图像和脑电的连续情绪识别方法

基于多模态生理数据的连续情绪识别技术在多个领域有重要用途,但碍于被试数据的缺乏和情绪的主观性,情绪识别模型的训练仍需更多的生理模态数据,且依赖于同源被试数据.本文基于人脸图像和脑电提出了多种连续情绪识别方法.在人脸图像模态,为解决人脸图像数据集少而造成的过拟合问题,本文提出了利用迁移学习技术训练的多任务卷积神经网络模型...     

Emotion recognition improvement using normalized formant supplementary features by hybrid of DTW-MLP-GMM model

In recent four decades, enormous efforts have been focused on developing automatic speech recognition systems to extract linguistic information, but much research is needed to decode the paralinguistic information such as speaking styles and emotion. The effect of using first three normalized formant frequencies and pitch frequency as supplementary features on improving the performance of an emotion recognition system that uses Mel-frequency cepstral coefficients and energy-related features, as the components of feature vector, is investigated in this paper. The normalization is performed using a dynamic time warping-multi-layer perceptron hybrid model after determining the frequency range that is most affected by emotion. To reduce the number of features, fast correlation-based filter and analysis of variations (ANOVA) methods are used in this study. Recognizing of the emotional states is performed using Gaussian mixture model. Experimental results show that first formant (F₁)-based warping and ANOVA-based feature selection result in the best performance as compared to other simulated systems in this study, and the average emotion recognition accuracy is acceptable as compared to most of the recent researches in this field.     

语音情感智能识别的建模与仿真

语音情感信息具有非线性、信息冗余、高维等复杂特点,数据含有大量噪声,传统识别模型难以消除冗余和噪声信息,导致语音情感识别正确率十分低.为了提高语音情感识别正确率,利用小波分析去噪和神经网络的非线性处理能力,提出一种基于过程神经元网络的语音情感智能识别模型.采用小波分析对语音情感信号进行去噪处理,利用主成分分析消除语音情感特征中的冗余信息,采用过程神经元网络对语音情感进行分类识别.仿真结果表明,基于过程神经元网络的识别模型的识别率比K近邻提高了13％,比支持向量机提高了8.75％,该模型是一种有效的语音情感智能识别工具.     

SVM-based hierarchical architectures for handwritten Bangla character recognition

We propose support vector machine (SVM) based hierarchical classification schemes for recognition of handwritten Bangla characters. A comparative study is made among multilayer perceptron, radial basis function network and SVM classifier for this 45 class recognition problem. SVM classifier is found to outperform the other classifiers. A fusion scheme using the three classifiers is proposed which is marginally better than SVM classifier. It is observed that there are groups of characters having similar shapes. These groups are determined in two different ways on the basis of the confusion matrix obtained from SVM classifier. In the former, the groups are disjoint while they are overlapped in the latter. Another grouping scheme is proposed based on the confusion matrix obtained from neural gas algorithm. Groups are disjoint here. Three different two-stage hierarchical learning architectures (HLAs) are proposed using the three grouping schemes. An unknown character image is classified into a group in the first stage. The second stage recognizes the class within this group. Performances of the HLA schemes are found to be better than single stage classification schemes. The HLA scheme with overlapped groups outperforms the other two HLA schemes.     

Blind digital modulation classification in software radio using the optimized classifier and feature subset selection

Automatic recognition of digital modulations plays an important role in various applications such as software defined radio. This study investigates the design of an accurate system for recognition of digital modulations. First, an efficient system is introduced that includes two main modules: the feature extraction module and the classifier module. First module extracts a suitable combination of the higher order moments up to eighth, higher order cumulants up to eighth and instantaneous characteristics of digital modulations. These features are applied for the first time in this area. In the classifier module, several supervised classifiers, such as multilayer perceptron neural network, radial basis function and multi-class support vector machine based classifier are investigated. By experimental study, we choose the best classifier for recognition of the considered modulations. Then, we propose a hybrid heuristic recognition system to which an optimization module is added to improve the generalization performance of the classifier. This module optimizes the classifier design by searching for the best value of the parameters that tune its discriminant function (kernel parameters selection) and upstream by looking for the best subset of features that feed the classifier. Simulation results show that the proposed system has a very high recognition accuracy. This high efficiency is achieved with little features, which have been selected using particle swarm optimizer.     

基于组合特征和BTSVM的电能质量扰动识别

为了克服单一特征不能完全表征各种暂态扰动信号特征的不足,提出了一种基于组合特征和二叉树结构支持向量机相结合的电能质量多分类方案。利用小波包变换对扰动信号进行分解,提取特定频带下信号的能量,利用S变换获得扰动信号的模矩阵,从中提取出特征信息,然后将多频带信号的能量和对应的S变换特征信息组合得到组合特征。对依据聚类思想设计出的二叉树结构支持向量机分类器进行了训练和测试。仿真结果表明,该方法具有较好的准确性和识别速度,能够有效识别常见扰动信号,平均识别率提高了6%以上,测试总用时缩短0.06秒,训练时间减小1.8秒。     

Facial expression recognition – A real time approach

Face localization, feature extraction, and modeling are the major issues in automatic facial expression recognition. In this paper, a method for facial expression recognition is proposed. A face is located by extracting the head contour points using the motion information. A rectangular bounding box is fitted for the face region using those extracted contour points. Among the facial features, eyes are the most prominent features used for determining the size of a face. Hence eyes are located and the visual features of a face are extracted based on the locations of eyes. The visual features are modeled using support vector machine (SVM) for facial expression recognition. The SVM finds an optimal hyperplane to distinguish different facial expressions with an accuracy of 98.5%.     

基于光流特征与高斯LDA的面部表情识别算法

文中提出了一种人脸表情识别的新方法,该方法采用动态的光流特征来描述人脸表情的变化差异,提高人脸表情的识别率。首先,计算人脸表情图像与中性表情图像之间的光流特征;然后,对传统的线性判断分析方法(Linear Discriminant Analysis,LDA)进行扩展,采用高斯LDA方法对光流特征进行映射,从而得到人脸表情图像的特征向量;最后,设计多类支持向量机分类器,实现人脸表情的分类与识别。在JAFFE和CK人脸表情数据库上的表情识别实验结果表明,该方法的平均识别率比3种对比方法的高出2%以上。