基于多分类器组合的手写体数字识别

本文提出了一个基于多分类器组合的手写体数字识别方法。文中首先给出了一个客观评价分类器性能的参数,其后基于此参数提出了多分类器的组合方法,并从理论上研究了此方法的一些性质,本文实验采用Ｃｏｎｃｏｒｔｄｉａ大学模式识别与机器智能中心的手写体数字数据库,在实验中,使用了９个利用不同特征分类器进行组合,组合后识别率、拒识率和可靠性分别可达到９７．０５％,２．０５％,９９．０８％。     

基于轮廓和统计特征的手写体数字识别

提出了数字规范化模板特征,并利用这一特征与轮廓分段特征相结合对手写体数字进行识别。首先使用基于轮廓分段特征的分类器进行识别,通过提高拒识率获得高可靠性的分类结果。然后由基于数字规范化模板特征的分类器对前一级分类器的拒识样本分类。实验结果表明分别基于这两个特征的分类器在分类结果上具有较强的互补性。实验的数据为真实支票上采集的10000个手写体数字样本,该方法的识别率为98.06%。     

手写体数字的识别

本文针对煤气储存罐体上高度的手写数字,由图象传感器获取十个数字手写体的图象信号进行数字识别,依据手写体字符“有效行”的特征提取,提出了并列的双BP神经网络的识别方法,对手写体数字的识别获得了较好的辨识效果。     

手写体数字识别技术的研究

手写体数字识别特征提取方面，有模板匹配，统计特征和结构特征，在分类器设计上有基于距离的分类器和神经网络分类器等，分析和评价了这些问题后，指出今后的研究方向应在特征综合，分类器集成以及新的分类器的研究上。     

用神经网络分类器识别非限制手写体数字

人工神经得识别图象有效工具，但许多研究人员认为，神经网络尚不能处理一此诸如识别手写体数字的难题。文中，作者提出了三种新型的神经网络分类识别器，专用于识别复杂图形：（１）多重多层感知（ＭＬＰ）分类器；（２）隐含马可失模型（ＨＭＭ）／ＭＬＰ混合分类顺；（３）适配结构自组织变换（ＳＯＭ）分类器。为了验证上述分类（识别）器的性能，各项实验均采用加拿大蒙特利尔Ｃｏｎｃｏｒｄｉａ大学数据库所提供的非限制手写体     

通过识别手写体数字比较神经网络与最贴近相邻分类器之性能

本文比较了两种识别手写体数字的技术，各以二维（２Ｄ）空间快速傅里叶变换（ＦＦＴ）系数，几何差动（ｍｏｍｅｎｔ）和拓扑特性等进行比较，分别采用一种逆向传播神经网络和一种最贴近相邻（ｎｅａｒｅｓｔ－ｎｅｉｇｈｂｏｒ）分类器，评价识别特性与运算条件，比较结果表明，神经网络解决复杂问题性能远优于相邻分类器，而且成本也低。     

基于BP人工神经网络的手写体数字识别

手写体数字识别是模式识别研究领域多年来的热点,BP人工神经网络是目前应用最广泛的神经网络模型之一。将两者融合并结合Matlab软件,提出了一种简单的基于BP神经网络数字识别的方法,仿真实验结果表明,该方法识别效果良好,准确率高,有一定实用性。     

基于结构特征的手写体数字识别算法

提出了基于结构特征的手写体数字识别方法。首先，采用14模板法进行细化，然后提取了点、线、圆等结构特征，并根据相关信息进行特征组合，最后采用粗细两阶段分类法进行分类。     

基于模版对比的手写体数字识别神经网络模型

针对现有手写体数字识别神经网络模型的不足,提出基于模版对比的改进方法。建立8×12像素的手写体数字0～9的标准模版,则模版中每个数字与其他数字之间存在一定的像素差异,以此作为标准模版差异值。由于书写存在不确定性,采用在一定范围内随机增大或减小标准模版差异值的方法来构建神经网络模型的训练样本、检验样本与测试样本。在遵循建模基本原则和步骤的情况下,建立了泛化能力较好的手写体数字识别的神经网络模型。实验表明：该方法建模便捷、实用性好,测试样本的正确识别率达99.6%以上。     

基于多阈值弱学习的Adaboost检测器

近年来基于Adaboost的人脸检测算法因其快速和可接受的检测率得到了成功的应用。但采用单阈值作弱分类器显得太弱难于适应复杂的统计分布,且训练过程较慢收敛。为克服这些困难,采用分类树作弱学习器,该学习器以贪婪的的方法用误差测度减少最大化的划分准则划分节点,并由此生成弱分类器,然后采用RAB或GAB方法在给定数据和标签的训练集上将这些弱分类器提升为强分类器。实践结果表明采用多阈值作弱分类器能显著提高分类器性能。     

Handwritten digit recognition: benchmarking of state-of-the-art techniques

This paper presents the results of handwritten digit recognition on well-known image databases using state-of-the-art feature extraction and classification techniques. The tested databases are CENPARMI, CEDAR, and MNIST. On the test data set of each database, 80 recognition accuracies are given by combining eight classifiers with ten feature vectors. The features include chaincode feature, gradient feature, profile structure feature, and peripheral direction contributivity. The gradient feature is extracted from either binary image or gray-scale image. The classifiers include the k-nearest neighbor classifier, three neural classifiers, a learning vector quantization classifier, a discriminative learning quadratic discriminant function (DLQDF) classifier, and two support vector classifiers (SVCs). All the classifiers and feature vectors give high recognition accuracies. Relatively, the chaincode feature and the gradient feature show advantage over other features, and the profile structure feature shows efficiency as a complementary feature. The SVC with RBF kernel (SVC-rbf) gives the highest accuracy in most cases but is extremely expensive in storage and computation. Among the non-SV classifiers, the polynomial classifier and DLQDF give the highest accuracies. The results of non-SV classifiers are competitive to the best ones previously reported on the same databases.     

基于量子神经网络的手写体数字识别方法研究

手写体数字识别问题是模式识别领域的一个重要研究课题.提出了一种基于多层激励函数的量子神经网络和多级分类器组合的手写体数字识别方法,采用MNIST数据库进行训练和测试.实验结果表明,该识别方法在识别率和可靠性方面均有很好的效果,同时也体现出量子神经网络用于模式识别的优越性和潜力.     

Part-based methods for handwritten digit recognition

In this paper, we intensively study the behavior of three part-based methods for handwritten digit recognition. The principle of the proposed methods is to represent a handwritten digit image as a set of parts and recognize the image by aggregating the recognition results of individual parts. Since part-based methods do not rely on the global structure of a character, they are expected to be more robust against various deformations which may damage the global structure. The proposed three methods are based on the same principle but different in their details, for example, the way of aggregating the individual results. Thus, those methods have different performances. Experimental results show that even the simplest part-based method can achieve recognition rate as high as 98.42% while the improved one achieved 99.15%, which is comparable or even higher than some state-of-the-art method. This result is important because it reveals that characters can be recognized without their global structure. The results also show that the part-based method has robustness against deformations which usually appear in handwriting.     

Handwritten digit recognition by means of a holographic associative memory

In this paper, a holographic associative memory (HAM) is proposed for recognizing handwritten variations of the ten digits. First, the handwritten characters were taken from the NIST standard database in order to extract relevant features from each one of them. Each digit was thus represented as a vector of 112 features constructed by dividing each character into 16 equal-sized partitions, each one used to extract seven different features for recognition. Second, these feature vectors, and reduced combinations of them, were input to train several HAM systems respectively. Then, all these memories were tested with a new set of patterns and the lowest-error HAM was chosen as the best training set. The features used in this last memory were taken as the most significant variables for describing each digit in the database. Finally, these most significant features were used to show the behaviour of the recognition rate when training the HAM with reduced training sets. Some final conclusions are reported and future work directions are proposed.     

基于深度卷积自编码神经网络的手写数字识别研究

针对提高不同笔体下的手写识别准确率进行了研究,将深度卷积神经网络与自动编码器相结合,设计卷积自编码器网络层数,形成深度卷积自编码神经网络。首先采用双线性插值方法分别对MNIST数据集与一万幅自制中国大学生手写数字图片进行图像预处理,然后先使用单一MNIST数据集对深度卷积自编码神经网络进行训练与测试;最后使用MNIST与自制数据集中5 000幅混合,再次训练该网络,对另外5 000幅进行测试。实验数据表明,所提深度卷积自编码神经网络在MNIST测试集正确率达到99.37%,有效提高了准确率;且5 000幅自制数据集模型测试正确率达99.33%,表明该算法实用性较强,在不同笔体数字上得到了较高的识别准确率,模型准确有效。     

基于二叉树和Adaboost算法的纸币号码识别

运用一种快速弱分类器训练算法和高速缓存策略来加速Adaboost算法的训练。集成学习算法Adaboost能够精确构建二分类器,运用二叉树型结构快速灵活地将纸币号码识别转化为一系列的Adaboost二分类问题。实验结果证明, 快速Adaboost训练算法能加快训练速度,基于二叉树和Adaboost的纸币号码识别系统具有较好的识别率和处理速度,已经应用在点钞机、清分机和ATM中。     

脱机手写数字识别方法

脱机手写体数字识别有着重大的使用价值,特征提取占据了重要的位置.提出了一种通过拓扑特征构造的特征提取新方法,利于了9种特征对数字进行特征提取,然后利用分类树的方法将数字进行分类.最后,在本科学生手写数字图像样本库上的试验结果表明,提出的特征提取方法不仅具有很快的运算能力,而且较大幅度地提高了识别率.     

Adaboost算法的脸谱识别系统应用设计

研究了灰度值、中值滤波的图像预处理方法和Haar特征提取思想计算多尺度下相同特征.本文基于Adaboost算法针对同一个训练集训练不同的分类器,并将弱分类器进行集合,构成一个更强的最终分类器,实现了脸谱识别系统.通过验证脸谱识别系统,实现了对视频流中脸谱的准确定位,达到了无拖影、噪声少及识别准确的预期.