基于奇Gabor滤波器与Rayleigh分布的边缘检测

为了自适应地更好地进行边缘检测,提出了一个基于奇Gabor滤波器与Rayle igh分布的边缘检测方法。在边缘响应获取中,由于该方法改进了原有的基于奇Gabor滤波器的边缘响应获取方法,从而提高了计算效率,并且避免了原算法对初始梯度方向估计的依赖。同时根据奇Gabor滤波器的一阶微分属性,可对其边缘输出响应利用Rayle igh分布进行拟合。为克服已有算法中阈值选择的局限性,还提出了一种基于Rayle igh分布的非线性自适应阈值选择方法。实验结果表明,所提出的边缘检测方法具有较好的检测性能和自适应性。     

基于融合的显微图像Gabor边缘提取算法

不同参数Gabor滤波器都具有各自的频率选择和方向选择特性,图像中纹理基元可以利用多个方向和中心频率Gabor滤波器组提取出来的频谱值来表示.据此提出一种适应于显微图像的Gabor滤波边缘检测算法.使用特定不同方向Gabor滤波边缘提取算子对图像进行边缘信息提取,获得不同方向上边缘特征信息,对其进行分析和融合提取图像边缘.运用该方法时所获不同方向的图像边缘进行自适应融合,获得的图像边缘较理想,模糊的边缘得到增强,并有效地消除了噪声.实验结果表明,该算法对显微图像处理有效,检测到的边缘清晰.     

利用Gabor方向导数相关矩阵的角点检测

为了提高角点检测的准确率,提出了一种使用图像的Gabor方向导数构建相关矩阵来进行图像角点检测的算法。算法首先通过Canny边缘检测算法提取检测图像的边缘轮廓;然后使用Gabor滤波器对图像进行平滑,利用每一个边缘像素和其邻近像素的Gabor方向导数构建相关矩阵,若相关矩阵的归一化特征值的和大于预定阈值并且是局部极大值,则标记该像素为角点。算法利用邻近像素Gabor方向导数之间的相关信息提取角点,与传统的基于轮廓的角点检测算法相比,检测性能更加稳健。实验结果表明：在含噪声和无噪声情况下,提出的算法检测到的真实角点更多,而错误角点更少,整体性能有明显提升     

基于频谱分析的高分辨率遥感图像边缘特征检测研究

针对高分辨率遥感图像的边缘特征,提出了一种基于频谱分析的图像边缘检测方法.首先对南京市主城区典型地物QuickBird图像进行傅里叶变换,分析频谱能量的角向分布特征,对最大角向能量分布曲线求一阶导数,将其峰值作为边缘检测滤波器的中心频率.通过设计方向Gabor滤波器进行频域滤波,达到图像边缘特征检测的目的.结果表明,进行频谱分析能够确定图像边缘特征的最佳截止频率,从而为高分辨率遥感图像边缘特征检测提供一种新方法.     

基于边缘检测器组合的密集边缘检测

本文提出了基于多个边缘检测器组合的密集边缘检测方法 ,并从理论上阐述了此方法的性质 .在实验中 ,采取了组合中值混合滤波器、Teboul变分法和最优的 Gabor滤波器的方式 ,随后用组合的边缘检测器对人脑横切片图和取自 Vis Tex数据库的图像进行分割 .实验结果表明此方法是有效的 .     

基于特征融合的非接触式掌纹识别

由于单一的特征描述掌纹中的所有信息,容易导致识别准确率低,因此提出一种边缘特征与纹理特征相结合的掌纹识别方法。先使用整体嵌套边缘检测模型和Gabor滤波器分别提取掌纹的边缘特征和纹理特征,再通过特征融合方法融合两种特征。最后,将融合后的特征图像输入到卷积神经网络,并得出分类结果。通过在不同的公开掌纹数据集上进行对比实验,结果表明本文方法取得了良好的结果。     

多通道奇Gabor梯度相关矩阵的角点检测算法

为了抑制边缘轮廓平滑导致角点定位精度的下降,提出多通道奇Gabor梯度相关矩阵的角点检测算法。该算法是在Gabor滤波器的基础上,利用8个通道的奇Gabor滤波器对输入图像进行变换;然后利用每个像素与其相邻像素的Gabor梯度相关性构造自相关矩阵,若像素点的自相关矩阵对应的归一化特征值的和是局部极大值,则标记为角点。实验显示,与Harris算法、曲率尺度空间(CSS)算法等经典算法相比,该算法的平均正确检测率提高了约17.74%,平均定位误差降低了约18.15%。结果表明,所提出的算法具有更好的检测性能,并获得了较高的角点检测率及较好的定位精度。     

基于Gabor滤波的头部CT图像分割算法

针对传统图像分割算法在头部CT图像分割时存在的易受光线、伪影等噪声干扰等问题,提出一种基于Gabor滤波的头部CT图像分割算法。首先使用Gabor滤波器对头部CT图像进行滤波,虑除图像中的光线以及伪影等噪声,然后使用Gaussian滤波器对图像进行平滑操作,最后使用二阶微分算子：Laplacian边缘检测算子对图像进行分割处理。实验结果表明：提出的基于Gabor滤波的头部CT图像分割算法能够有效的分割出头部CT图像边缘,并对头部CT图像中常见噪声伪影,具有很强的鲁棒性。     

Gabor滤波器组实现颅脑图像的边缘快速提取

在医学图像处理过程中,针对一般方法提取颅脑图像边缘不是很清晰的情况,提出了一种基于短时傅立叶变换的新的Gabor滤波方法。该方法通过选取一组能够覆盖整个频域的滤波器,分别提取图像的局部边缘信息,然后按照一定的规则将提取出局部信息的多幅图像整合成一幅图像。普通Gabor滤波计算量较大,耗时较长,而该文所述方法能显著地减少运算量。并且相对于其他几种滤波方法也表现出定位准确,检测效果明显,以及鲁棒性较好的特点。     

基于局部图像锐化的自适应模糊边缘检测算法

为了准确检测出模糊边缘的位置 ,对用小尺度滤波器检测模糊边缘时噪声影响检测效果的原因进行了分析 ,依据这些噪声点在模糊边缘附近的统计分布规律 ,提出了一种用于图像锐化的阈值计算方法 ,算法自适应地计算图像不同区域对应的图像锐化阈值 ,并用这个值来锐化模糊边缘图像 ,实现对模糊边缘的准确提取。实验结果证明该算法能有效去除模糊边界处的干扰点 ,明显改进了小尺度滤波器提取模糊边缘的性能     

基于Gabor滤波器和SVM分类器的红外车辆检测

提出一种基于Gabor滤波器和支持向量机(SVM)的红外车辆检测方法。该方法首先应用阈值分割并结合边检测确定候选区域；其次应用Gabor滤波器对选定的车辆和背景样本集进行特征提取，训练SVM分类器。这里提出一种特征加权技术，即根据特征矢量中邻近分量的离散程度对其自身进行加权；最后应用SVM进行分类检测，以判断候选区域内是否存在车辆。实验数据表明了该方法的实用性和可行性。     

Gabor filter-based edge detection

It is common practice to utilize evidence from biological and psychological vision experiments to develop computational models for low-level feature extraction. The receptive profiles of simple cells in mammalian visual systems have been found to closely resemble Gabor filters. Daugman proved that Gabor filters achieve joint minimal joint uncertainty. These results led researchers to develop computational models based on Gabor filters for several low-level vision applications such as edge detection, texture classification, optical flow estimation and data compression. In this paper, the performance of a Gabor odd filter-based edge detector is investigated using the measures proposed by Canny. Based on this performance analysis a design criterion for one-dimensional (1D) Gabor filter-based edge detector is derived. It is shown that this design criterion also holds good for a two-dimensional (2D) Gabor filter-based edge detector. Experimental results are presented to demonstrate the performance of the Gabor filter-based edge detector.     

An automated inspection system for textile fabrics based on Gabor filters

This paper studies the application of advanced computer image processing techniques for solving the problem of automated defect detection for textile fabrics. A new defect detection scheme is proposed, which consists of an odd symmetric real-valued Gabor filter, an even symmetric real-valued Gabor filter and one smoothing filter. In developing the scheme, the Gabor filters are designed on the basis of the texture features extracted optimally from a non-defective fabric image by using a Gabor wavelet network (GWN). The performance of the proposed defect detection scheme is evaluated off-line by using a set of fabric images taken from a database consisting of a wide variety of homogeneous fabric images. The results exhibit accurate defect detection with low false alarms, thus showing the effectiveness and robustness of the proposed scheme. To evaluate the performance of the proposed defect detection scheme further, real-time tests are conducted by using a prototyped automated defect detection system. The experimental results obtained further confirm the efficiency, effectiveness and robustness of the proposed detection scheme.     

Optimized Gabor features for mass classification in mammography

Gabor filter bank has been successfully used for false positive reduction problem and the discrimination of benign and malignant masses in breast cancer detection. However, a generic Gabor filter bank is not adapted to multi-orientation and multi-scale texture micro-patterns present in the regions of interest (ROIs) of mammograms. There are two main optimization concerns: how many filters should be in a Gabor filter band and what should be their parameters. Addressing these issues, this work focuses on finding optimizing Gabor filter banks based on an incremental clustering algorithm and Particle Swarm Optimization (PSO). We employ an SVM with Gaussian kernel as a fitness function for PSO. The effect of optimized Gabor filter bank was evaluated on 1024 ROIs extracted from a Digital Database for Screening Mammography (DDSM) using four performance measures (i.e., accuracy, area under ROC curve, sensitivity and specificity) for the above mentioned mass classification problems. The results show that the proposed method enhances the performance and reduces the computational cost. Moreover, the Wilcoxon signed rank test over the significance level of 0.05 reveals that the performance difference between the optimized Gabor filter bank and non-optimized Gabor filter bank is statistically significant.     

基于Gabor滤波器的图像边缘检测算法的研究

采用Canny算子进行边缘检测时,需人工设定高低2个阈值,对不同的图像采用相同的阈值,边缘检测效果差异很大。这一点限制了Canny算子在实际中的应用。针对这一问题,本文提出了一种基于Gabor奇部滤波器的边缘检测方法,在不同的尺度下分别采用非极大值抑制,然后利用Canny算子在高低阈值图像中查找边缘点的方法对图像进行边缘检测,无需人为的设定任何参数。实验结果表明这种算法不但克服了Canny算法中人为设定阈值的缺陷,而且能有效地去除了图像中的伪边缘。     

Optimizing Gabor Filter Design for Texture Edge Detection and Classification

An effective and efficient texture analysis method, based on a new criterion for designing Gabor filter sets, is proposed. The commonly used filter sets are usually designed for optimal signal representation. We propose here an alternative criterion for designing the filter set. We consider a set of filters and its response to pairs of harmonic signals. Two signals are considered separable if the corresponding two sets of vector responses are disjoint in at least one of the components. We propose an algorithm for deriving the set of Gabor filters that maximizes the fraction of separable harmonic signal pairs in a given frequency range. The resulting filters differ significantly from the traditional ones. We test these maximal harmonic discrimination (MHD) filters in several texture analysis tasks: clustering, recognition, and edge detection. It turns out that the proposed filters perform much better than the traditional ones in these tasks. They can achieve performance similar to that of state-of-the-art, distribution based (texton) methods, while being simpler and more computationally efficient.