基于小波包变换的纹理分类的水冷壁表面模式识别

提出了一种基于小波包变换的纹理分类的锅炉水冷壁表面模式识别算法,该算法选用纹理特征作为冷壁表面模式分类依据,使用小波包计算纹理的能量分布,并以能量分布作为分类特征,用BP神经网络进行了分类识别。     

基于小波变换和蚁群算法的纹理分割

纹理分割是图像模式识别中的关键步骤,但直到现在仍然没有一种有效的方法能够解决。本文提出了一种新的基于小波变换和蚁群算法的纹理分割方法。该方法首先用小波变换提取图像不同频带的纹理特征,然后提出具有聚类能力的蚁群算法数学模型,并用这个模型来进行分割。实验结果表明,该方法是一种有效的纹理分割方法。     

基于小波包变换的模糊判决纹理分类

提出一种基于小波包变换的模糊判决纹理分类方法,采用图象的完全树结构小波变换提取多分辨率纹理特征,模糊判决分类器通过引入隶属度函数对待征模糊化,反映了各类纹理样本间存在的差异及随机噪声等畸变因素赞成的抽取特征值存在的不确定性,提高了纹理分类算法对噪声或畸变的鲁棒性,通过实验获得了较满意的结果。     

基于小波包框架的纹理分割

本文描述了利用小波包框架变换和包络检测算法提取图像在不同尺度下的纹理特征.该变换是一种冗余的变换,具有位移不变的特点,同时又能对任意感兴趣的尺度范围作进一步的分解.实验表明,利用小波包框架提取纹理的特征优于小波变换或小波框架变换.结合包络检测算法,能达到较高的正确分割率.     

基于复值小波包概率模型的纹理分类研究

为准确描述纹理,发挥复值小波包变换多方向通道等优点,首次基于复值小波包对纹理采用概率模型进行自适应描述,并同最大似然分类方法结合进行纹理分类.提出融合各类纹理最优描述的方法,将图库分类正确率从85%提高到93%.     

基于Log-Polar和DT-CWT的旋转不变纹理分类算法

提出了一种基于对数-极坐标变换和双树复数小波变换的旋转不变纹理分类算法。该方法首先对纹理图像进行对数-极坐标变换将旋转转化为平移,再用具有平移不变性的双树复数小波对变换后的图像滤波并计算各子带的能量值组成旋转不变特征向量,最后利用支持向量机算法实现纹理图像的分类。将本方法与其它旋转不变纹理分类算法进行比较,实验结果表明,提出的算法能有效地提高正确分类率。     

基于复小波和支持向量机的纹理分类法*

针对图像纹理分类问题,提出了一种将二元树复小波变换与支持向量机相结合的分类方法,通过二元树复小波变换对纹理图像进行四层分解,提取各子频带小波系数模的均值和标准方差组成特征向量,利用支持向量机作为分类器实现纹理图像分类。对20类Brodatz纹理图像的分类实验表明,提出的方法具有较高的分类精度,在有限训练样本的情况下比传统的分类算法平均正确率有10%左右的提高,体现了该方法的有效性和良好的泛化能力。     

基于Radon变换和SWT的旋转不变纹理分类

提出了一种应用Radon变换和离散平稳小波变换(SWT)的旋转不变纹理分类算法。该方法首先对纹理图像进行Radon变换将旋转转化为平移,再用具有平移不变性的离散平稳小波对变换后的图像滤波并计算各子带的能量值组成旋转不变特征向量,最后利用支持向量机实现纹理图像的分类。将本方法与其它旋转不变纹理分类法进行比较,实验结果表明,提出的方法能有效地提高正确分类率。     

V-系统与Radon变换相结合的纹理分类算法

为了对尺度和旋转变换下的纹理图像进行正确的分类,将Radon变换和V-系统相结合,提出一种纹理分类的算法.首先利用Radon变换将图像的旋转化为平移,再对Radon变换后的图像进行V-变换;利用V-系统的多小波特性,经过一系列的降采样分解过程得到图像在V-系统下的各层次能量表达,并将这些能量作为纹理图像的特征描述.由于V-系统的多小波特性以及Radon变换对旋转的消除,使得文中的特征描述在图像的放缩和旋转变换下有较强的鲁棒性.在通用纹理数据库中的纹理分类实验结果表明了该算法的优越性能.     

新的纹理图像特征提取方法

提出了一种新的基于非下采样Contourlet变换的纹理特征提取方法.首先对纹理图像进行非下采样Contourlet变换,然后提取不同尺度、不同方向上变换系数矩阵的均值和方差作为特征向量,大大降低了特征维数,并利用BP神经网络进行训练和仿真,实现了纹理图像的自动分类.实验结果表明,与小波包变换和改进的LBP纹理算子等方法相比,该方法能取得更好的分类效果.     

Analysis of wavelet packet and statistical textures for object-oriented classification of forest-agriculture ecotones using SPOT 5 imagery

Textural features of high-resolution remote sensing imagery are a powerful data source for improving classification accuracy because using only spectral information is not sufficient for the classification of objects with within-field spectral variability. This study presents the methods of using an object-oriented texture analysis algorithm for improving high-resolution remote sensing imagery classification, including wavelet packet transform texture analysis, the grey-level co-occurrence matrix (GLCM) and local spatial statistics. Wavelet packet transform texture analysis, with the method of optimization and selection of wavelet texture for feature extraction, is a good candidate for object-oriented classification. Feature optimization is used to reduce the data dimensions in combinations of textural sub-bands and spectral bands. The result of the classification accuracy assessment indicates the improvement of texture analysis for object-oriented classification in this study. Compared with the traditional method that uses only spectral bands, the combination of GLCM homogeneity and spectral bands increases the overall accuracy from 0.7431 to 0.9192. Furthermore, wavelet packet transform texture analysis is the optimal method, increasing the overall accuracy to 0.9216 using a smaller data dimension. Local spatial statistical measures also increase the classification total accuracy, but only from 0.7431 to 0.8088. This study demonstrates that wavelet packet and statistical textures can be used to improve object-oriented classification; specifically, the texture analysis based on the multiscale wavelet packet transform is optimal for increasing the classification accuracy using a smaller data dimension.     

Ant colony clustering analysis based intelligent fault diagnosis method and its application to rotating machinery

Fault diagnosis is crucial to improve reliability and performance of machinery. Effective feature extraction and clustering analysis can mine useful information from large amounts of raw data and facilitate fault diagnosis. This paper presents a novel intelligent fault diagnosis method based on ant colony clustering analysis. Vibration signals acquired from equipment are decomposed by wavelet packet transform, after which sub-bands of signals are clustered by ant colony algorithm, and each cluster as a set of data is analyzed from pattern of frequency band perspective for selecting intrinsic features reflecting operation condition of equipment, and thus fault diagnosis model is established to combine the extracted major features with given fault prototypes from historical data. The classification process for fault diagnosis is carried out using Euclidean nearness degree based on the established model. Furthermore, an improved ant colony clustering algorithm is proposed to adjust comparison probability dynamically and detect outliers. When compared with other clustering algorithms, the algorithm has higher convergence speed to meet requirements of real-time analysis as well as further improvement of accuracy. Finally, effectiveness and feasibility of the proposed method is verified by vibration signals acquired from a rotor test bed.     

Log-polar wavelet energy signatures for rotation and scale invariant texture classification

Classification of texture images is important in image analysis and classification. This paper proposes an effective scheme for rotation and scale invariant texture classification using log-polar wavelet signatures. The rotation and scale invariant feature extraction for a given image involves applying a log-polar transform to eliminate the rotation and scale effects, but at same time produce a row shifted log-polar image, which is then passed to an adaptive row shift invariant wavelet packet transform to eliminate the row shift effects. So, the output wavelet coefficients are rotation and scale invariant. The adaptive row shift invariant wavelet packet transform is quite efficient with only O(n /spl middot/ log n) complexity. A feature vector of the most dominant log-polar wavelet energy signatures extracted from each subband of wavelet coefficients is constructed for rotation and scale invariant texture classification. In the experiments, we employed a Mahalanobis classifier to classify a set of 25 distinct natural textures selected from the Brodatz album. The experimental results, based on different testing data sets for images with different orientations and scales, show that the proposed classification scheme using log-polar wavelet signatures outperforms two other texture classification methods, its overall accuracy rate for joint rotation and scale invariance being 90.8 percent, demonstrating that the extracted energy signatures are effective rotation and scale invariant features. Concerning its robustness to noise, the classification scheme also performs better than the other methods.     

基于离散多小波变换的纹理分类

纹理分析在遥感、医学图像处理、计算机视觉及基于纹理的按内容检索的图像数据库等许多重要领域均有着广泛的应用.引入多小波理论,提出了基于多小波分解的纹理图像分类.通过一系列的实验并与单小波进行比较,实验结果表明,多小波分解比金字塔小波分解或小波包分解其分类准确率更优.     

Comparison of wavelet families for texture classification by using wavelet packet entropy adaptive network based fuzzy inference system

Recently, significant of the robust texture image classification has increased. The texture image classification is used for many areas such as medicine image processing, radar image processing, etc. In this study, a new method for invariant pixel regions texture image classification is presented. Wavelet packet entropy adaptive network based fuzzy inference system (WPEANFIS) was developed for classification of the twenty 512 × 512 texture images obtained from Brodatz image album. There, sixty 32 × 32 image regions were randomly selected (overlapping or non-overlapping) from each of these 20 images. Thirty of these image regions and other 30 of these image regions are used for training and testing processing of the WPEANFIS, respectively. In this application study, Daubechies, biorthogonal, coiflets, and symlets wavelet families were used for wavelet packet transform part of the WPEANFIS algorithm, respectively. In this way, effects to correct texture classification performance of these wavelet families were compared. Efficiency of WPEANFIS developed method was tested and a mean %93.12 recognition success was obtained.     

A new optimum feature extraction and classification method for speaker recognition: GWPNN

Speech and speaker recognition is an important topic to be performed by a computer system. In this paper, an expert speaker recognition system based on optimum wavelet packet entropy is proposed for speaker recognition by using real speech/voice signal. This study contains both the combination of the new feature extraction and classification approach by using optimum wavelet packet entropy parameter values. These optimum wavelet packet entropy values are obtained from measured real English language speech/voice signal waveforms using speech experimental set. A genetic-wavelet packet-neural network (GWPNN) model is developed in this study. GWPNN includes three layers which are genetic algorithm, wavelet packet and multi-layer perception. The genetic algorithm layer of GWPNN is used for selecting the feature extraction method and obtaining the optimum wavelet entropy parameter values. In this study, one of the four different feature extraction methods is selected by using genetic algorithm. Alternative feature extraction methods are wavelet packet decomposition, wavelet packet decomposition – short-time Fourier transform, wavelet packet decomposition – Born–Jordan time–frequency representation, wavelet packet decomposition – Choi–Williams time–frequency representation. The wavelet packet layer is used for optimum feature extraction in the time–frequency domain and is composed of wavelet packet decomposition and wavelet packet entropies. The multi-layer perceptron of GWPNN, which is a feed-forward neural network, is used for evaluating the fitness function of the genetic algorithm and for classification speakers. The performance of the developed system has been evaluated by using noisy English speech/voice signals. The test results showed that this system was effective in detecting real speech signals. The correct classification rate was about 85% for speaker classification.     

基于小波包特征的纹理影像分割

利用小波包变换来检测纹理图象上的灰度变化，以得到多分辨率、多方向性的微观统计特征图象，在此基础上用Ｅｎｖｅｌｏｐ算法提取基于边缘信息的纹理特征，为了克服纹理特征之间的相关性，采用了子空间分类器对纹理特征图象进行分类，取得了较好的分割效果。