自适应多结构元形态学边缘检测方法

对自适应选取结构元权值以及如何有效去除混合噪声是多结构元形态学边缘检测中尚待解决的两个问题,在深入研究各种形态学边缘检测方法的基础上,提出了基于灰度距离逻辑函数和基于边缘方差两种自适应多结构元形态学边缘检测方法。首先对原始图像进行最优阈值分割二值化,其次从灰度距离和边缘方差两个角度分别实现结构元的自适应选取,最后选择形态算子进行边缘检测。方法具有更好的抗噪性和灵活性,能更加精确的体现原有图像的边缘方向信息。通过仿真实验,验证了方法的可行性和有效性。     

基于顺序形态变换的图像边缘检测

该文分析了顺序形态学和普通形态学运算的特点,在此基础上研究了基于顺序形态运算的边缘检测,通过对原始图像采用不同百分位值和结构元素的顺序形态变换,可以选择不同阈值和图像中目标信号分布范围,结合Canny检测算子能有效检测灰度接近背景的目标区域的边界。     

基于局部连接度和差异度算子的水平集纹理图像分割

目的 复杂纹理的图像分割一直是图像分割的难题,现有的一些纹理图像分割方法主要通过提取图像确定方向的灰度变化特征或者提取图像的局部灰度相似性特征得到特征图像,从而进行纹理图像的分割,然而,自然纹理中普遍存在局部形态相似和方向不确定的现象,导致现有方法不能准确地分割纹理图像。方法 本文提出局部连接算子和局部差异算子来描述局部纹理的形态相似性和局部纹理的差异度。一方面,通过设定一定阈值,将局部区域的灰度差异分为两类,分析两类差异的分布特征,从而提取图像的形态特性及局部连接度算子;另一方面,设置一种无方向性的灰度差异分析算子,提取图像局部的灰度差异值从而得到局部差异度算子。两个算子结合以更好地提取纹理图像的局部特征,然后通过融合局部相似度特征、局部差异度特征和灰度信息,构造水平集能量泛函,进而通过最小化能量泛函实现纹理图像分割。结果 相比基于Gabor变换、结构张量、局部相似度因子的纹理分割方法,提出的局部算子能够更好地区分自然图像的不同纹理区域,且对实验图像的平均分割准确率高达97%,远高于其他方法。因此,提出的模型对于自然纹理图像具有更好的分割效果。结论 本文提出了两种新颖的纹理特征局部描述子：局部连接度算子和局部差异度算子,能够有效地提取纹理特征,且有一定的互补性。实验表明,提出的方法对于复杂自然纹理图像具有良好的分割效果。     

基于形态梯度运算的遥感图像边缘检测

针对常规线性边缘检测器处理遥感图象时细节丢失严重的缺点,介绍了数学形态学基本理论,讨论了数学形态学在边缘检测中的应用.形态学的灰度梯度运算是在经典形态变换基础上提出的一类非线性算子.对于结构元素的选取作了一定的说明.另外,还与传统线性算子的处理结果进行了比较.通过计算机对遥感图像的模拟实验表明：基于形态灰度梯度运算的遥感图像边缘检测方法,不但几何意义明确,易于构造,而且性能也优于传统检测算子,证实了该方法的可行性.     

基于多结构元顺序形态变换的灰度图像边缘检测

在简要介绍顺序形态变换的基本概念及相关性质和对顺序形态变换进行边缘检测的原理进行阐述,以及对结构元素和百分位对边缘检测的影响进行讨论的基础上,根据图像形态学多刻度形态滤波的思想,从抑制噪声的角度对基本边缘检测算子进行推广和扩展,首先构造了3种边缘检测算子,并从理论上分析了算子的特性;然后将多结构元与图像边缘进行匹配,提出了3种广义顺序形态边缘检测算子并给出了一般表达形式;最后着重探讨了多结构元素及二重混合顺序形态变换百分位值p、q的选取原则.实验结果表明,该边缘检测算子在抑制噪声对图像边缘的影响和保持图像细节方面,优于传统的边缘检测算子和普通的形态边缘检测器.     

基于形态学多结构元边缘提取方法的研究

通过对传统形态学边缘提取方法的分析,提出了基于形态学多结构元边缘提取算子,该算子既有良好的边缘提取特性,又可很好地解决了噪声抑制和保持图像边缘细节之间的矛盾,通过灰度加权平均值作为阈值进行二值化,更加突出了边缘效果。实验表明:基于形态学的多结构元边缘提取算子,具有较高的噪声抑制能力,能够完成复杂背景下的边缘提取。     

图像降噪组合滤波优化算法

论文利用中值滤波算子和灰度数学形态学中的开、闭算子设计了一种用于灰度图像降噪处理的优化组合滤波算法。提出了一种简单、实用的评价函数用于算法的优化过程。该算法能根据输入噪声图像自动调整算子的组合结构获得最佳的滤波输出,并克服了中值滤波算法在处理灰度图像时对噪声强度的敏感问题。该优化算法简洁、耗时少。算法的实用性用计算机进行了仿真验证。     

基于多结构元素的数学形态学的遥感图像边缘检测方法

提出了一种边缘检测的有效算法。该算法在数学形态学的基础上，针对图像中噪声和边缘形态的不同建立了多结构元素，利用灰度形态变换原理进行边缘提取。实验表明，与经典的边缘检测算子相比，该算法具有很好的边缘提取能力，但其抗噪能力较差。为此，探讨性地提出了基于小波变换和数学形态学相结合的边缘提取方法。     

一种基于改进算子的形态学边缘检测算法

针对传统的边缘检测算法存在的不足,文中基于修正的边缘检测算子和形态滤波思想,采用多尺度和多结构元素,提出了一种新的多结构多尺度形态学灰度图像边缘检测算法,通过构造新算子实现边缘检测。在该算法中,分别将各个结构元素下的检测结果进行加权求和,得到图像的边缘。实验表明,和其他的传统或形态学边缘检测算法相比,文中方法具有更好的噪声抑制能力,而且边缘定位准确,检测到的边缘轮廓更加清晰完整。     

基于动态结构元的药柱表面图像边缘检测

以某产品药柱表面图像边缘检测为例,提出了一种基于动态形态学结构元和SUSAN算子相结合的图像边缘检测算法.该算法采用动态形态学结构元得到梯度图像,根据梯度图像利用SUSAN算子进行边缘检测.采用动态形态学结构元得到的梯度图像服从统一分布,有利于边缘提取,克服了采用固定形态学结构元不能适应不同的梯度图像的不足.通过与so.bel和固定形态学结构元的边缘检测算子进行对比实验,实验结果表明,该方法具有较好的边缘提取能力,抗噪性能好,对药柱表面图像处理具有很好的实际应用价值.     

A new approach to morphological color image processing

This paper presents a new approach to the generalization of the concepts of grayscale morphology to color images. A new vector ordering scheme is proposed, infimum and supremum operators are defined, and the fundamental vector morphological operations are extracted. The basic properties of the presented vector morphology are described and its similarities to grayscale morphological operators are pointed out. The main advantages of the proposed methodology are that is vector preserving and provides improved results in many morphological applications. Furthermore, experimental results demonstrate the applicability of the proposed technique in a number of image processing and analysis problems, such as noise removal, edge detection and skeleton extraction.     

Fast Algorithms for Area Morphology

Acton, S. T., Fast Algorithms for Area Morphology, Digital Signal Processing11 (2001) 187–203Efficient algorithms are developed for area morphology. As opposed to traditional morphological operations that alter grayscale images via a concatenation of order statistic filters, the area morphological operators manipulate connected components within the image level sets. Essentially, the area morphology filters are capable of removing objects based on the object area solely. These operators can then be effectively used in important multiscale and scale space tasks such as object-based coding and hierarchical image searches. Unfortunately, the traditional implementation of these filters based on level set theory precludes real-time implementation. This paper reviews previous fast algorithms and introduces a pyramidal approach. The full pyramidal algorithm is over 1000 times faster than the standard algorithm for typical image sizes. The paper provides supporting simulation results in terms of computational complexity and solution quality.     

A Euclidean distance transform using grayscale morphologydecomposition

A fast and exact Euclidean distance transformation using decomposed grayscale morphological operators is presented. Applied on a binary image, a distance transformation assigns each object pixel a value that corresponds to the shortest distance between the object pixel and the background pixels. It is shown that the large structuring element required for the Euclidean distance transformation can be easily decomposed into 3×3 windows. This is possible because the square of the Euclidean distance matrix changes uniformly both in the vertical and horizontal directions. A simple extension for a 3D Euclidean distance transformation is discussed. A fast distance transform for serial computers is also presented. Acting like thinning algorithms, the version for serial computers focuses operations only on the potential changing pixels and propagates from the boundary of objects, significantly reducing execution time. Nonsquare pixels can also be used in this algorithm. An example application, shape filtering using arbitrary sized circular dilation and erosion, is discussed. Rotation-invariant basic morphological operations can be done using this example application     

Implementation of morphological filters using coordinate logic operations

In this paper we present a methodology for performing morphological operations using coordinate logic operations. Coordinate logic operations are simple and fast because they are logic operations among the corresponding binary values of the image pixels. Coordinate logic (CL) filters are a family of fast non-increasing, non-linear filters, which are based on coordinate logic operations. CL filters exhibit analogous properties to those of the morphological filters but due to their different definition they display slightly different response. This is revoked in this paper by using appropriate image gray level quantization and mapping of the resulting levels to a specific set of decimal numbers. Based on this approach some fast efficient implementations of morphological filters using CL operators are proposed.     

Soft Morphological Filtering Using a Fuzzy Model and its Application to Colour Image Processing

Abstract Soft morphological filters form a class of filters with many desirable properties. They were introduced to improve the behaviour of standard morphological filters in detail preservation and noise elimination. In this paper, a framework for soft morphological colour image processing using a fuzzy model is introduced. This extends the standard colour morphological operators in the same way that soft greyscale morphology extends the standard greyscale morphology theory. The primary and secondary operations of the new soft morphological approach are defined. The proposed operators are less sensitive to image distortion and to small variations in the shape of the objects, and perform significantly better in impulse noise removal problems, compared to standard morphological operators. Experimental results of the application to real colour images demonstrate these advantageous characteristics of the new operators. Additionally, illustrative examples that exhibit the applicability of the proposed methodology to edge detection problems are also included.An erratum to this article can be found at     

Probabilistic pseudo-morphology for grayscale and color images

Mathematical morphology offers popular image processing tools, successfully used for binary and grayscale images. Recently, its extension to color images has become of interest and several approaches were proposed. Due to various issues arising from the vectorial nature of the data, none of them imposed as a generally valid solution. We propose a probabilistic pseudo-morphological approach, by estimating two pseudo-extrema based on Chebyshev inequality. The framework embeds a parameter which allows controlling the linear versus non-linear behavior of the probabilistic pseudo-morphological operators. We compare our approach for grayscale images with the classical morphology and we emphasize the impact of this parameter on the results. Then, we extend the approach to color images, using principal component analysis. As validation criteria, we use the estimation of the color fractal dimension, color textured image segmentation and color texture classification. Furthermore, we compare our proposed method against two widely used approaches, one morphological and one pseudo-morphological.     

A general framework for tree-based morphology and its applications to self-dual filtering

This paper presents a tree-based framework for producing self-dual morphological operators, based on a tree-representation complete inf-semilattice (CISL). The idea is to use a self-dual tree transform to map a given image into the above CISL, perform one or more morphological operations there, and map the result back to the image domain using the inverse tree transform. We also present a particular case of this general framework, involving a new tree transform, the Extrema-Watershed Tree (EWT). The operators obtained by using the EWT in the above framework behave like classical morphological operators, but in addition are self-dual. Some application examples are provided: pre-processing for OCR and dust and scratch removal algorithms, and image denoising. We also explore first steps towards obtaining tree transforms that induce a CISL on the image domain as well.     

一种新颖的灰度形态学算子

数学形态学方法是非线性图像处理中的一种重要方法,在二值图像处理中已获得了广泛的应用,但在灰度图像处理中的应用却相对有限,文中从形态学算子构造的角度出发,提出了一种具有较强实用能力的灰度形态学算子的构造方法。