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Color image segmentation based on 3-D clustering

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Abstract

In this paper, a new segmentation algorithm for color images based on mathematical morphology is presented. Color image segmentation is essentially a clustering process in 3-D color space, but the characteristics of clusters vary severely, according to the type of images and color coordinates. Hence, the methodology employs the scheme of thresholding the difference of Gaussian smoothed 3-D histogram to get the initial seeds for clustering, and then uses a closing operation and adaptive dilation to extract the number of clusters and their representative values, and to include the suppressed bins during Gaussian smoothing, without a priori knowledge on the image. This procedure also implicitly takes into account the statistical properties, such as the shape, connectivity and distribution of clusters. Intensive computer simulation has been performed and the results are discussed in this paper. The results of the simulation show that the proposed segmentation algorithm is independent of the choice of color coordinates, the shape of clusters, and the type of images. The segmentation results using the k-means technique are also presented for comparison purposes.

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... Teori himpunan digunakan untuk menggambarkan struktur geometris secara statistik. Morfologi matematika sekarang banyak digunakan dalam visi komputer, analisis gambar, dan aplikasi pengenalan pola seperti segmentasi gambar berwarna dalam ruang 3-D [4], metode deteksi tepi citra penginderaan jauh [5], dan pemrosesan citra medis [6], di antara yang lain. Prinsip utama di balik morfologi matematika adalah menggunakan elemen struktural dengan ketajaman tertentu untuk mengukur dan mendeteksi objek yang terkait. ...
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... (a) if δ(c i , x j ) < jndc i , then update the membership of x j inF i at t + 1 iteration by µF i (x j )(t + 1) = 1.0 (15) (b) if δ(c k , x j ) < jndc k , for k = i,c k ∈C then update the membership of x j inF i at t + 1 iteration by µF i (x j )(t + 1) = 0.0 (16) (c) if condition (a) and (b) are not satisfied for all c k ∈C, k = 1..c, then update the membership of x j inF i at t + 1 iteration by ...
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... Histopatolojik görüntülerin bölütlenmesinde gerçekleştirilen çalışmalar CNN tabanlı eğitim mimarilerini kullanmayan klasik yöntemler ve derin öğrenme tabanlı yöntemler olarak iki sınıfta incelenebilir. Kmeans [1], morphology [2], watershed [3], thresholding [4], Active Contour Models (ACM) [5] gibi yöntemler bölütleme alanında kullanılan klasik yöntemlerdendir. ...
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... The classes for color segmentation are built by means of a cluster identification scheme which is performed either by an analysis of the color histogram [4] or by a cluster analysis procedure [5]. When the classes are constructed, the pixels are assigned to one of them by means of a decision rule and then mapped back to the original image plane to produce the segmentation. ...
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... La méthode la plus classique est sans doute l'algorithme des centres mobiles (ou ses variantes les nuées dynamiques et les k-means) qui est grandement utilisé tant dans la quantification vectorielle que dans la compression de données. Il est applicable dans n'importe quel espace colorimétrique : PARK [PARK98] l'emploie dans l'espace RVB alors que WEEKS et HAGUE [WEEKS97] le font dans l'espace HSI. Ces méthodes de classification sont non hiérarchiques. ...
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... La técnica de segmentación del histograma por línea divisoria de aguas, introducida en Watson (1987), fue desarrollada por Soille (1996) para la partición morfológica de imágenes satélite multiespectrales. Después se han propuesto diferentes variantes (Postaire et al., 1993;Petrou et al., 1998;Sang et al. 1998;Park et al. 1998; Géraud et al., 2001), así como otras aplicaciones tal que la detección de caras en imágenes color (Albiol et al., 2001). ...
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Chapter
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... (a) if δ(c i , x j ) < jndc i , then update the membership of x j inF i at t + 1 iteration by µF i (x j )(t + 1) = 1.0 (15) (b) if δ(c k , x j ) < jndc k , for k = i,c k ∈C then update the membership of x j inF i at t + 1 iteration by µF i (x j )(t + 1) = 0.0 (16) (c) if condition (a) and (b) are not satisfied for all c k ∈C, k = 1..c, then update the membership of x j inF i at t + 1 iteration by ...
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A novel ultrasound image segmentation algorithm, which is based on the spectral cluster ensemble, is proposed to segment ultrasound images with low SNR. Firstly, the improved total variation model is used to eliminate noise in ultrasound. Then cluster ensemble approach which integrates K-means clusters and improved spectral cluster algorithm, is applied to segment ultrasound images. At last, the segmentation result is clustered again using K-means cluster to get the ultimate segmentation result. A large amount of experimental results have proved that our method outperforms many state-of-arts methods in the aspect of segmentation.
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In this work, we develop a statistical framework for data clustering which uses hierarchical Dirichlet processes and Beta-Liouville distributions. The parameters of this framework are leaned using two variational Bayes approaches. The first one considers batch settings and the second one takes into account the dynamic nature of real data. Experimental results based on a challenging problem namely visual scenes categorization demonstrate the merits of the proposed framework.
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Fuzzy C-means (FCM) is an unsupervised clustering technique that is often used for the unsupervised segmentation of multivariate images. In traditional FCM the clustering is based on spectral information only and the geometrical relationship between neighbouring pixels is not used in the clustering procedure. In this paper, the spatially guided FCM (SG-FCM) algorithm is presented which segments multivariate images by incorporating both spatial and spectral information. Spatial information is described by a geometrical shape description and can vary from a local neighbourhood to a more extended shape model such as Hough circle detection. A modified FCM objective function uses the spatial information as described by the shape model. This results in a segmented image in which the construction of the cluster prototypes is influenced by spatial information. The performance of SG-FCM is compared with both FCM and the sequence of FCM and a majority filter. The SG-FCM segmented image shows more homogeneous regions and less spurious pixels. Copyright © 2003 John Wiley & Sons, Ltd.
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We propose a color-image segmentation algorithm by unsupervised classification of pixels. The originality of the proposed approach consists in iteratively identifying pixel classes by taking into account both the pixel color distributions in several color spaces and their spatial arrangement in the image. In order to overcome the difficult problem of the color space choice, the algorithm selects the color space that is well suited to construct the class at each iteration step. The selection criterion is based on connectedness and color homogeneity measures of pixel subsets. In order to tune the sensitivity of segmentation, we introduce a hierarchical criterion that allows us to segment images with different numbers of regions as human observers do. Experiments carried out on the well-known Berkeley segmentation dataset show that this multicolor space approach succeeds in constructing classes that effectively correspond to regions in the image.
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Conference Paper
Color space dimensionality possesses main problem in fast processing of color images so appropriate sampling of color images is very important. Unlike the existing statistical sampling algorithm, in this paper, a biologically inspired non-linear color image sampling technique has been proposed using non-uniform quantization of RGB space. Response of human retinal receptors to various light intensities is non-linear in nature. Buschbaum has qualitatively presented the non-linear tan-sigmoid model of the human vision as against the logarithmic and power law models. An experiment has been carried out on certified normal color vision observers in broad day light conditions to model their color vision. Readings of this experiment were used to compute the parameters of Red, Green and Blue color vision non-linearity presented by Buchsbaum. These parametric non-linearity equations were used to sample the color images and other applications of the work have been proposed. The non-linearity equations with respective parameters represent the models of Red, Green and Blue color vision receptors. Physiological limitations and facts of human vision have been utilized to compute the parameter.
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In this paper we introduce a lattice algebra clustering technique for segmenting digital images in the Red-Green- Blue (RGB) color space. The proposed technique is a two step procedure. Given an input color image, the first step determines the finite set of its extreme pixel vectors within the color cube by means of the scaled min-W and max-M lattice auto-associative memory matrices, including the minimum and maximum vector bounds. In the second step, maximal rectangular boxes enclosing each extreme color pixel are found using the Chebychev distance between color pixels; afterwards, clustering is performed by assigning each image pixel to its corresponding maximal box. The two steps in our proposed method are completely unsupervised or autonomous. Illustrative examples are provided to demonstrate the color segmentation results including a brief numerical comparison with two other non-maximal variations of the same clustering technique.
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In this paper we present some extensions to the k-means algorithm for vector quantization that permit its efficient use in image segmentation and pattern classification tasks. It is shown that by introducing state variables that correspond to certain statistics of the dynamic behavior of the algorithm, it is possible to find the representative centers of the lower dimensional manifolds that define the boundaries between classes, for clouds of multi-dimensional, multi-class data; this permits one, for example, to find class boundaries directly from sparse data (e.g., in image segmentation tasks) or to efficiently place centers for pattern classification (e.g., with local Gaussian classifiers). The same state variables can be used to define algorithms for determining adaptively the optimal number of centers for clouds of data with space-varying density. Some examples of the application of these extensions are also given. Copyright c fl Massachusetts Institute of Technology, 19...
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The segmentation of images should generate segments which correspond to objects, parts of objects, or groups of objects which appear in the image. This paper presents a description of a general segmentation method which can be applied to many different types of scenes. It describes the segmentation method in detail and discusses the potential performance of other segmentation techniques on general scenes. Also presented is a subset of the images which have been analyzed using this technique and a summary of the computational effort required. Details of some of the major programs are given in the appendix.
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In this paper, a segmentation algorithm for color images based on the thresholding and the fuzzy c-means (FCM) techniques is presented. The scale-space filter is used as a tool for analyzing the histograms of three color components. The methodology uses a coarse-fine concept to reduce the computational burden required for the FCM. The coarse segmentation attempts to segment coarsely using the thresholding technique, while the fine segmentation assigns the pixels, which remain unclassified after the coarse segmentation, to the closest class using the FCM. Attempts also have been made to compare the performance of the proposed algorithm with other existing algorithms—Ohlander's, Rosenfeld's, and Bezdek's. Intensive computer simulation has been performed and the results are discussed in this paper. The simulation results indicate that the proposed algorithm yields the most accurate segmented image on the color coordinate proposed by Ohta et al., while requiring a reasonable amount of computational effort.
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A new hybrid method is presented that combines the scale space filter (SSF) and Markov random field (MRF) for color image segmentation. The fundamental idea of the SSF is to use the convolution of Gaussian functions and image-histogram to generate a scale space image and then find the proper interval bounded by the local extrema of the derivatives. The Gaussian function is with zero mean and varied standard deviation. Using the SSF the different scaled histogram is separated into intervals corresponding to peaks and valleys. The MRF makes use of the property that each pixel in an image has some relationship with other pixels. The basic construction of an MRF is a joint probability given the original data. The original data is the image that is obtained from the source and the result is called the label image. Because the MRF needs a number of segments before it converges to the global minimum, the SSF is exploited to do coarse segmentation (CS) and then MRF is used to do fine segmentation (FS) of the images. Basically, the former is histogram-based segmentation, whereas the latter is neighborhood-based segmentation. Finally, experimental results obtained from using SSF alone, MRF using iterated conditional mode (ICM), and MRF using Gibbs sampling are compared.
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When analyzing color pictures one often requires that the image be segmented into meaningful regions based upon the color characteristics of the scene. Such a problem can assume two different forms. The first variation arises when particular color space characteristics are known and the goal is to detect and extract image regions which possess the given color characteristics. The second case arises when there is no a priori knowledge about the color space characteristics of the scene and the goal is to segment the scene into meaningful regions which possess uniform color space characteristics. This paper describes an interactive system which uses a decision surface modeling approach to solve the first case and uses clustering techniques in the three-dimensional color space to solve the second case. A set of examples is presented and the performance of the system is evaluated.
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In color image processing various kinds of color features can be calculated from the tristimuli R, G, and B. We attempt to derive a set of effective color features by systematic experiments of region segmentation. An Ohlander-type segmentation algorithm by recursive thresholding is employed as a tool for the experiment. At each step of segmenting a region, new color features are calculated for the pixels in that region by the Karhunen Loeve transformation of R, G, and B data. By analyzing more than 100 color features which are thus obtained during segmenting eight kinds of color pictures, we have found that a set of color features, , and , are effective. These three features are significant in this order and in many cases a good segmentation can be achieved by using only the first two. The effectiveness of our color feature set is discussed by a comparative study with various other sets of color features which are commonly used in image analysis. The comparison is performed in terms of both the quality of segmentation results and the calculation involved in transforming data of R, G, and B to other forms.
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Many image segmentation techniques are available in the literature. Some of these techniques use only the gray level histogram, some use spatial details while others use fuzzy set theoretic approaches. Most of these techniques are not suitable for noisy environments. Some works have been done using the Markov Random Field (MRF) model which is robust to noise, but is computationally involved. Neural network architectures which help to get the output in real time because of their parallel processing ability, have also been used for segmentation and they work fine even when the noise level is very high. The literature on color image segmentation is not that rich as it is for gray tone images. This paper critically reviews and summarizes some of these techniques. Attempts have been made to cover both fuzzy and non-fuzzy techniques including color image segmentation and neural network based approaches. Adequate attention is paid to segmentation of range images and magnetic resonance images. It also addresses the issue of quantitative evaluation of segmentation results.
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This paperr describes a clustering algorithm for segmenting the color images of natural scenes. The proposed method operates in the 1976 CIE (L∗, a∗, b∗)-uniform color coordinate system. It detects image clusters in some circular-cylindrical decision elements of the color space. This estimates the clusters' color distributions without imposing any constraints on their forms. Surfaces of the decision elements are formed with constant lightness and constant chromaticity loci. Each surface is obtained using only 1D histogramsof the L∗, H°, C∗ cylindrical coordinates of the image data or the extracted feature vector. The Fisher linear discriminant method is then used to project simultaneously the detected color clusters onto a line for 1D thresholding. This permits utilization of all the color properties for segmentation and inherently recognizes their respective cross correlation. In this respect, the proposed algorithm also differs from the multiple histogram-based thresholding schemes.
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For the past decade, many image segmentation techniques have been proposed. These segmentation techniques can be categorized into three classes, (1) characteristic feature thresholding or clustering, (2) edge detection, and (3) region extraction. This survey summarizes some of these techniques. In the area of biomedical image segmentation, most proposed techniques fall into the categories of characteristic feature thresholding or clustering and edge detection.
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Image segmentation is the process by which an original image is partitioned into some homogeneous regions. In this paper, a novel multiresolution color image segmentation (MCIS) algorithm which uses Markov random fields (MRF's) is proposed. The proposed approach is a relaxation process that converges to the MAP (maximum a posteriori) estimate of the segmentation. The quadtree structure is used to implement the multiresolution framework, and the simulated annealing technique is employed to control the splitting and merging of nodes so as to minimize an energy function and therefore, maximize the MAP estimate. The multiresolution scheme enables the use of different dissimilarity measures at different resolution levels. Consequently, the proposed algorithm is noise resistant. Since the global clustering information of the image is required in the proposed approach, the scale space filter (SSF) is employed as the first step. The multiresolution approach is used to refine the segmentation. Experimental results of both the synthesized and real images are very encouraging. In order to evaluate experimental results of both synthesized images and real images quantitatively, a new evaluation criterion is proposed and developed
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A low-level segmentation methodology based upon fuzzy clustering principles is developed. The approach utilizes region growing concepts and a pyramid data structure for the hierarchical analysis of aerial images. It is assumed that measurement vectors corresponding to perceptually homogeneous regions cluster together in the measurement space. The fuzzy c-means (FCM) clustering algorithm is used in the formulation. Utilization of the fuzzy partitioning allows one to derive a correspondence between the cluster membership function values and (the proportions of) the classes constituting a region. Thus cluster membership values can be used to split mixture regions into smaller regions at a higher resolution level. The feasibility of the methodology is evaluated using a three-channel Landsat image. The results show that the FCM clustering can be used in the single-level segmentation; and that cluster membership function values derived using this algorithm can be utilized effectively as indicators of region homogeneity.
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Vector quantization is intrinsically superior to predictive coding, transform coding, and other suboptimal and {em ad hoc} procedures since it achieves optimal rate distortion performance subject only to a constraint on memory or block length of the observable signal segment being encoded. The key limitation of existing techniques is the very large randomly generated code books which must be stored, and the computational complexity of the associated encoding procedures. The quantization operation is decomposed into its rudimentary structural components. This leads to a simple and elegant approach to derive analytical properties of optimal quantizers. Some useful properties of quantizers and algorithmic approaches are given, which are relevant to the complexity of both storage and processing in the encoding operation. Highly disordered quantizers, which have been designed using a clustering algorithm, are considered. Finally, lattice quantizers are examined which circumvent the need for a code book by using a highly structured code based on lattices. The code vectors are algorithmically generated in a simple manner rather than stored in a code book, and fast algorithms perform the encoding algorithm with negligible complexity.
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In this paper, we present an approach to color image understanding that can be used to segment and analyze surfaces with color variations due to highlights and shading. The work is based on a theory - the Dichromatic Reflection Model - which describes the color of the reflected light as a mixture of light from surface reflection (highlights) and body reflection (object color). In the past, we have shown how the dichromatic theory can be used to separate a color image into two intrinsic reflection images: an image of just the highlights, and the original image with the highlights removed. At that time, the algorithm could only be applied to hand-segmented images. This paper shows how the same reflection model can be used to include color image segmentation into the image analysis. The result is a color image understanding system, capable of generating physical descriptions of the reflection processes occurring in the scene. Such descriptions include the intrinsic reflection images, an image segmentation, and symbolic information about the object and highlight colors. This line of research can lead to physicsbased image understanding methods that are both more reliable and more useful than traditional methods.
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One of the key tools in applying physics-based models to machine vision has been the analysis of color histograms. In the mid-1980s it was recognized that the color histogram for a single inhomogeneous surface with highlights will have a planar distribution in color space. It has since been shown that the colors do not fall randomly in a plane, but form clusters at specific points. The shape of the histogram is related not only to the illumination color and object color, but also to such non-color properties as surface roughness and imaging geometry. We present here an algorithm for analyzing color histograms that yields estimates of surface roughness, phase angle between the camera and light source, and illumination intensity. These three scene parameters are related to three histogram measurements. However the relationship is complex and cannot be solved analytically. Therefore we have developed a method for estimating these properties by interpolating between histograms that come f...
Color information for region segmentation, Comput. »ision Graphics Image Process
  • Yu-Ichi Ohta
  • Takeo Kanade
  • Toshiyuki Sakai
Yu-Ichi Ohta, Takeo Kanade and Toshiyuki Sakai, Color information for region segmentation, Comput. »ision Graphics Image Process. 13, 224—241 (1980).
Color image segmentation based on the 3D clustering and mor-phological operators
  • S H Park
  • I D Yun
  • S U Lee
S. H. Park, I. D. Yun and S. U. Lee, Color image segmentation based on the 3D clustering and mor-phological operators, 2nd Asian Conf. on Comput. »ision, Vol.-III. pp. 253—257. Singapore, December 1995.
  • R M Haralick
  • L G Shapiro
R. M. Haralick and L. G. Shapiro, Computer and Robot »ision: Vol. I, II. Addison-Wesley Reading, Massachusetts (1993).