基于统计和谱图的图像阈值分割方法研究
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摘要
图像分割是图像处理与分析的关键环节,也是计算机视觉研究领域的一个经典难题。在一些图像分割的应用中,目标像素的灰度级有别于背景像素的灰度级。在这种情形下,阈值方法就成了-种简单而有效的图像分割方法。近年来,阈值分割受到了国内外研究者的广泛关注,并已被广泛应用于目标识别、机器视觉等领域。本文针对图像阈值分割方法进行了较为深入的研究,主要工作和研究成果如下:
     (1)经典的统计阈值方法将目标和背景的方差和作为阈值选择的准则,仅仅考虑了方差和,对目标和背景具有较大方差差异的图像分割的效果不理想。针对此问题,首先提出了一种融合了方差和与方差差异的统计阈值方法,较好地解决了这类图像的分割问题。此外,针对目标和背景具有相似统计分布的特性,设计了一种统计阈值方法,并将其与图(graph)的等周常数联系起来,进一步说明了此方法的合理性。在一系列红外图像上的实验结果证实了它的有效性。
     (2)近年来,基于谱图的图像分割技术成了图像分割领域一个新的研究热点。这类方法将图像映射为带权无向图,把图像分割问题转化为图划分问题,通过求图划分代价函数的最小值来获得对应图像的分割。等周图割是一种新近的图谱图像分割方法,它不属于阈值分割范畴,未能充分利用图像中像素点的灰度信息,直接应用到灰度图像的分割中效果不甚理想。为此,结合等周图割和阈值分割思想提出了一种二级阈值方法。此方法将等周图割中的等周率作为阈值选择的准则,并在此基础上,利用人类视觉感知的特性来缩小阈值搜索的范围,缩短分割时间,提升分割性能。此外,由于二级阈值方法只能将图像分割成两个部分,无法满足实际分割中将图像分成多个部分的需要。针对此问题,将基于等周图割的二级阈值方法扩展到多级阈值分割中,提出了一种快速有效的迭代策略来获得多个分割阈值,优化了等周率的计算,引入了聚类数自动确定的方法来选择合理的阈值个数。扩展后的多级阈值方法不仅能自动确定阂值个数,而且其时间复杂性与阈值个数无关,这使其避免了传统多级阈值方法的缺陷,即随着阈值个数的增大,分割性能不稳定且计算复杂度呈指数增长。在一系列图像上的实验结果表明了此方法的有效性。
     (3)基于过渡区域的阈值分割方法是近年来兴起的一类图像分割方法。相对于图像的非过渡区域(目标和背景)而言,过渡区域具有更为频繁而强烈的灰度变化。根据图像过渡区域的特点,提出了一种基于灰度差异的过渡区域提取及阈值分割方法,将像素点的灰度级与其局部邻域的灰度均值之间的绝对差异作为描述子来刻画过渡区域。灰度差异仅笼统地反映了像素点与其邻域均值之间的差异,未能反映像素点与邻域内像素点之间的具体差异。为此,提出了一种改进的灰度差异作为过渡区域描述子,利用像素点与其邻域内像素点的绝对灰度差异之和来刻画过渡区域。在一系列图像上的实验结果表明,改进的灰度差异对过渡区域的刻画是行之有效的。另外,针对传统过渡区域描述子未同时考虑灰度变化的频率和幅度,对过渡区域刻画不完整的问题,提出了一种融合了局部复杂度和局部方差的过渡区域描述子。它利用局部复杂度来刻画局部窗口内灰度变化的频率,同时借助局部方差来反映灰度变化的幅度,最后将局部复杂度和局部方差归一化后综合为一个新的描述子。在红外以及文本等一系列图像上的实验结果表明,相对于传统的过渡区域描述子,综合后的描述子能更准确地刻画过渡区域。新方法准确地提取了图像的过渡区域,获得了更好的阈值分割结果,且抗噪性能更强。
     (4)针对现有的过渡区域方法未考虑人类视觉感知特性的问题,提出了一种无监督的过渡区域提取方法。此方法先利用人类视觉感知的特性,结合图像的统计特征,以种无监督的方式来估计过渡区域的灰度范围,实现图像变换,然后利用局部方差作为描述子提取图像的过渡区域,进而获得最终的阈值分割结果。在工业无损检测等系列图像上的实验结果表明,图像变换过程保持了过渡区域的灰度变化,同时削弱了非过渡区域的灰度变化,简化了原图像,对后续的过渡区域提取大有裨益。新方法明显改善了过渡区域提取的准确性,获得了更好的分割结果。此外,将图像变换的思想借鉴到了传统阈值分割中,提出了3种无监督的范围受限的阈值方法。相对于传统方法,范围受限的方法用变换后的图像替代原图像作为分割对象,既符合人类视觉感知的特点,又缩小了阈值搜索的范围,节省了运算时间。变换后的图像更简单,有利于后续的阈值分割。在工业无损检测等系列图像上的实验结果表明,与它们对应的传统方法相比,范围受限的阈值方法分割效果更好,分割速度与传统方法相当。
Image segmentation is a key step in image processing and analysis, and a classic difficulty in computer vision. There are some applications of image segmentation, where gray levels of object pixels are distinctive from those of background ones. In this case, image thresholding becomes a simple and effective image segmentation approach. During last few years, image thresholding has gotten wide attention from researchers at home and abroad, and has been widely applied to a lot of fields, such as target recognition and machine vision. The paper does comparatively deep research on image thresholding, and its main works and research results are as follows:
     (1) Classic statistical thresholding methods use variance sum of object and background classes as criteria for threshold selection. They only take variance sum into account, and fail to achieve satisfactory results when segmenting a kind of images, where variance discrepancy between the object and background classes is large. To solve the problem, a new statistical thresholding method combining variance sum and variance discrepancy is proposed in this paper. In addition, we present another statistical method for some images having similar statistical distributions on the object and background, and relate it with isoperimetric constant of a graph. This further shows the rationality of our method, and experimental results on a series of infrared images demonstrate its effectiveness.
     (2) Recently, image segmentation technique based on spectral graph is a new research hotspot. It regards an image as a weighted undirected graph, converts image segmentation problem into graph partitioning one, and implements image segmentation by minimizing certain cost function of graph partition. Among this kind of methods, isoperimetric cut is a newly developed one. However, the isoperimetric cut dose not belong to thresholding, and fail to adequately utilize gray level information of an image. This makes it unsuitable for gray level image segmentation. Here, we introduce the isoperimetric cut into image thresholding, and present a bilevel thresholding method for overcoming the above limitation. The proposed method uses isoperimetric ratio of the isoperimetric cut as criterion for threshold selection. Furthermore, characteristics of human visual perception are also utilized to reduce search range of thresholds, shorten segmentation time, and improve segmentation performance. The above bilevel thresholding method can only divide an image into two parts, and can not meet some practical segmentation tasks dividing an image into multiple parts. To solve the problem, we extend a bilevel method based on isoperimetric cut into multilevel thresholding. The extended method finds multiple thresholds by a fast and effective iterative scheme, simplifies computation of isoperimetric ratio, and introduces a way of automatically determining cluster number to adaptively choose reasonable threshold number. The new multilevel method can automatically determine threshold number, and its time complexity is independent of the threshold number. This makes our method avoid disadvantages of conventional multilevel thresholding ones, i.e., instability of segmentation performance and exponential growth of computational complexity with the increase of threshold number. Experimental results on a series of images show the effectiveness of our multilevel method.
     (3) Image thresholding based on transition region is a newly developed image segmentation technique. As compared with non-transition region (i.e., object and background regions), transition region of an image has more frequent and stronger gray level changes. On the basis of the characteristic of transition region, a transition region extraction and thresholding method based on gray level difference is proposed in this paper. The proposed method uses absolute difference between a pixel's gray level and the gray level average of its local neighborhood window as a descriptor for depicting transition region. The above gray level difference is very rough, and can not reflect the detailed difference between the pixel and other pixels in its neighborhood. Hence we present a modified gray level difference as a new transition region descriptor. The descriptor uses the sum of absolute gray level difference between the pixel and each pixel in its neighborhood to characterize transition region. Experimental results on a variety of images show that the modified gray level difference is effective on transition region description. In addition, conventional transition region descriptors do not take frequency and degree of gray level changes into account simultaneously, and fail to depict transition region comprehensively. To solve the problem, we present a new descriptor integrating local complexity and local variance. It uses local complexity to reflect frequency of gray level changes in local neighborhood window, meanwhile utilizes local variance to degree of the changes. Then local complexity and local variance are combined as a new transition region descriptor after being normalized respectively. Experimental results on a variety of images including infrared and text ones show that the new descriptor can depict transition region more accurately, as compared with conventional ones. And the corresponding method extracts transition region more accurately, obtains better thresholding results, and has stronger noise immunity.
     (4) Existing image thresholding methods based on transition region do not consider characteristics of human visual perception. An unsupervised transition region extraction and thresholding method is proposed to solve this problem. The proposed method first utilizes characteristics of human visual perception and statistical characteristics of an image to estimate gray level range of transition region for implementing image transformation in an unsupervised way, then uses local variance as descriptor to extract transition region, and finally obtains thresholding result. Experimental results on a variety of images including industrial nondestructive testing ones show that image transformation preserves gray level changes of transition region, meanwhile weakens gray level changes of non-transition region. This simplifies the original image, which should be helpful for subsequent transition region extraction. The new method obviously improves accuracy of transition region extraction, and obtains better sgemnetation results. In addition, we introduce the above image transformation into conventional thresholding, and present three unsupervised range-constrained thresholding methods. As compared with conventional approaches, range-constrained methods implement thresholding on the transformed image instead of the original one. This not only coincides with human visual perception, but also reduces search range of thresholds and saves computational time. The transformed image is simper than the original one, which should be helpful for subsequent image thresholding. Experimental results on a variety of images including nondestructive testing ones show that range-constrained methods have better segmentation quality, and segmentation speed is comparative with their counterparts.
引文
[1]Pal N R, Pal S K. A review on image segmentation techniques. Pattern Recognition,1993, 26(9):1277~1294
    [2]罗希平,田捷,诸葛婴,王靖,戴汝为.图像分割方法综述.模式识别与人工智能,1999,12(3):300~312
    [3]Haralick R M, Shapiro L G. Image segmentation techniques. Computer Vision, Graphics, and Image Processing,1985,29(1):100~132
    [4]刘锁兰.基于模糊理论的图像分割区域法研究.南京:南京理工大学博士论文,2008
    [5]Matalas L, Benjamin R, Kitney R. An edge detection technique using the facet model and parameterized relaxation labeling. IEEE Transactions on Pattern Analysis and Machine Intelligence,1997,19(4):328~341
    [6]Liang K H, Tjahjadi T, Yang Y H. Roof edge detection using regularized cubic b-spline fitting. Pattern Recognition,1997,30(5):719~728
    [7]Vincken K L, Koster A S E, Viergever M A. Probabilistic multiscale image segmentation. IEEE Transactions on Pattern Analysis and Machine Intelligence,1997,19(2):109~120
    [8]Tabb M, Ahuja N. Multiscale image segmentation by integrated edge and region detection. IEEE Transactions on Image Processing,1997,6(5):642~655
    [9]Wu M F, Shen H T. Representation of 3D surfaces by two-variable Fourier descriptors. IEEE Transactions on Pattern Analysis and Machine Intelligence,1998,20(8):858~863
    [10]Caselles V, Kimmel R, Sapiro G. Geodesic active contours. International Journal of Computer Vision,1997,22(1):61~79
    [11]Chan T F, Vese L A. Active contours without edges. IEEE Transactions on Image Processing,2001,10(2):266~277
    [12]Ziou D, Tabbone S. A multi-scale edge detector. Pattern Recognition,1993,26(9): 1305~1314
    [13]Brown M A, Blackwell K T, Khalak H G, Barbour G S, Vogl T P. Multi-scale edge detection and feature binding:an integrated approach. Pattern Recognition,1998,31(10): 1479~1490
    [14]冈萨雷斯著,阮秋琦,阮宇智等译.数字图像处理.第二版.北京:电子工业出版社,2003
    [15]Zhuang X, Huang Y, Palaniappan K, Zhao Y. Gaussian mixture density modeling, decomposition, and applications. IEEE Transactions on Image Processing,1996,5(9): 1293~1302
    [16]Ben-Hur A, Horn D, Siegelmann H T, Vapnik V. A support vector clustering method. In 15th International Conference on Pattern Recognition,2000,2:724~727
    [17]赵雪松,陈淑珍.综合全局二值化与边缘检测的图像分割方法.计算机辅助设计与图形学学报,2001,13(2):118~121
    [18]Chen Q, Sun Q, Heng P A, Xia D. A double-threshold image binarization method based on edge detector. Pattern Recognition,2008,41(4):1254~1267
    [19]Pal S K, King R A, Hashim A A. Automatic grey level thresholding through index of fuzziness and entropy. Pattern Recognition Letters,1983,1(3):141~146
    [20]Kim B G, Shim J I, Park D J. Fast image segmentation based on multi-resolution analysis and wavelets. Pattern Recognition Letters,2003,24(16):2995~3006
    [21]张立明.人工神经网络的模型及其应用.上海:复旦大学出版社.1993
    [22]Cheng K S, Lin J S, Mao C W. The application of competitive hopfield neural network to medical image segmentation. IEEE Transactions on Medical Imaging,1996,15(4):560~567
    [23]Wu Z, Leahy R. An optimal graph theoretic approach to data clustering:Theory and its application to image segmentation. IEEE Transactions on Pattern Analysis and Machine Intelligence,1993,15(11):1101~1113
    [24]Sarkar S, Soundararajan P. Supervised learning of large perceptual organization:Graph spectral partitioning and learning automata. IEEE Transactions on Pattern Analysis and Machine Intelligence,2000,22(5):504~525
    [25]Shi J, Malik J. Normalized cuts and image segmentation. IEEE Transactions on Pattern Analysis and Machine Intelligence,2000,22(8):888~905
    [26]Wang S, Siskind J M. Image segmentation with ratio cut. IEEE Transactions on Pattern Analysis and Machine Intelligence,2003,25(6):675~690
    [27]Grady L, Schwartz E L. Isoperimetric graph partitioning for image segmentation. IEEE Transactions on Pattern Analysis and Machine Intelligence,2006,28(3):469~475
    [28]Cao L, Bao P, Shi Z. The strongest schema learning GA and its application to multilevel thresholding. Image and Vision Computing,2008,26(5):716~724
    [29]Lei H, Cheng S, Ao M, Wu Y. Application of an improved genetic algorithm in image segmentation, Proceedings of International Conference on Computer Science and Software Engineering,2008,3:898~901
    [30]Fan S K S, Lin Y. A multi-level thresholding approach using a hybrid optimal estimation algorithm. Pattern Recognition Letters,2007,28(5):662~669
    [31]Maitra M, Chatterjee A. A hybrid cooperative-comprehensive learning based on PSO algorithm for image segmentation using multilevel thresholding. Expert systems and Applications,2008,34(2):1341~1350
    [32]Bazi Y, Bruzzone L, Melgani F. Image thresholding based on the EM algorithm and the generalized Gaussian distribution. Pattern Recognition,2007,40(2):619~634
    [33]Qiao Y, Hu Q, Qian G, Luo S, Nowinski W L. Thresholding based on variance and intensity contrast. Pattern Recognition,2007,40(2):596~608
    [34]Sang N, Li H, Peng W, Zhang T. Knowledge-based adaptive thresholding segmentation of digital subtraction angiography images. Image and Vision Computing,2007,25(8): 1263~1270
    [35]Sahoo P K, Arora G. Image thresholding using two-dimensional Tsallis-Havrda-Charvat entropy. Pattern Recognition Letters,2006,27(6):520~528
    [36]Saha B N, Ray N. Image thresholding by variational minimax optimization. Pattern Recognition,2009,42(5):843~856
    [37]Parker J R. Gray level thresholding in badly illuminated images. IEEE Transactions on Pattern Analysis and Machine Intelligence.1991,13(8):813~819
    [38]Lee S U, Chung S Y, Park R H. A comparative performance study of several global thresholding techniques for segmentation. Computer Vision, Graphics, and Image Processing, 1990,52(2):171~190
    [39]Otsu N. A threshold selection method from gray-level histograms. IEEE Transactions on Systems, Man, and Cybernetics,1979,9(1):62~66
    [40]Tsai W H. Moment-preserving thresholding:a new approach. Computer Vision, Graphics, and Image Processing,1985,29(3):377~393
    [41]Kittler J, Illingworth J. Minimum error thresholding. Pattern Recognition,1986,19(1): 41~47
    [42]Pun T. A new method for grey-level picture thresholding using the entropy of the histogram. Signal Processing,1980,2(3):223~237
    [43]Kapur J N, Sahoo P K, Wong A K C. A new method for gray-level picture thresholding using the entropy of the histogram. Computer Vision, Graphics, and Image Processing,1985, 29(3):273~285
    [44]Mason D, Lauder I J, Rutovitz D, Spowart G. Measurement of C-bands in human chromosomes. Computers in Biology and Medicine,1975,5:179~201
    [45]Wu A Y, Hong T H, Rosenfeld A. Threshold selection using quadtrees. IEEE Transactions on Pattern Analysis and Machine Intelligence,1982,4(1):90~94
    [46]Ahuja N, Rosenfeld A. A note on the use of second-order gray-level statistics for threshold selection. IEEE Transactions on Systems, Man and Cybernetics,1978,8(12): 895~899
    [47]Abutaleb A S. Automatic thresholding of gray-level pictures using two-dimensional entropy. Computer Vision, Graphics, and Image Processing,1989,47(1):22~32
    [48]Sahoo P K, Soltani S, Wong A K C. A survey of thresholding techniques. Computer Vision, Graphics, and Image Processing,1988,41(2):233~260
    [49]Yen J C, Chang F J, Chang S. A new criterion for automatic multilevel thresholding. IEEE Transactions on Image Processing,1995,4(3):370~378
    [50]Kohler R. A segmentation system based on thresholding. Computer Graphics and Image Processing,1981,15(4):319~338
    [51]闫成新.基于区域的图象分割技术研究.华中科技大学博士学位论文,2004
    [52]Gerbrands J J. Segmentation of noisy images. Ph.D. dissertation, Delft University, The Netherlands,1988
    [53]Zhang Y J, Gerbrands J J. Transition region determination based thresholding. Pattern Recognition Letters,1991,12 (1):13~23
    [54]Yan C, Sang N, Zhang T. Local entropy-based transition region extraction and thresholding. Pattern Recognition Letters,2003,24(16):2935-2941
    [55]Hu Q, Luo S, Qiao Y, Qian G. Supervised grayscale thresholding based on transition regions. Image and Vision Computing,2008,26(12):1677~1684
    [56]Sezgin M, Sankur B. Survey over image thresholding techniques and quantitative performance evaluation. Journal of Electronic Imaging,2004,13(1):146~165
    [57]Rosenfeld A, De la Torre P. Histogram concavity analysis as an aid in threshold selection. IEEE Transactions on Systems, Man and Cybernetics,1983,13(3):231~235
    [58]Halada L, Ososkov G A. Histogram concavity analysis by quasicurvature. Computers and Artificial Intelligence,1987,6(6):523~533
    [59]Whatmough R J. Automatic threshold selection from a histogram using the exponential hull. CVGIP:Graphical Models and Image Processing,1991,53(6):592~600
    [60]Sezan M I. A peak detection algorithm and its application to histogram-based image data reduction. Computer Vision, Graphics, and Image Processing,1990,49(1):36~51
    [61]Boukharouba S, Rebordao J M, Wendel P L. An amplitude segmentation method based on the distribution function of an image. Computer Vision, Graphics, and Image Processing, 1985,29(1):47~59
    [62]Tsai D M. A fast thresholding selection procedure for multimodal and unimodal histograms. Pattern Recognition Letters,1995,16(6):653~666
    [63]Ramesh N. Yoo J H, Sethi I K. Thresholding based on histogram approximation. IEE Proceedings of Vision, Image and Signal Processing,1995,142(5):271~279
    [64]Kampke T, Kober R. Nonparametric optimal binarization. Proceedings of 14th International Conference on Pattern Recognition,1998,1:27~29
    [65]Ridler T W, Calvard S. Picture thresholding using an iterative selection method. IEEE Transactions on Systems, Man and Cybernetics,1978,8:630~632
    [66]Leung C K, Lam F K. Performance analysis for a class of iterative image thresholding algorithms. Pattern Recognition,1996,29(9):1523~1530
    [67]Trussell H J. Comments on picture thresholding using iterative selection method. IEEE Transactions on Systems, Man and Cybernetics,1979,9(5):311~311
    [68]Yanni M K, Home E. A new approach to dynamic thresholding. Proceedings of 9th European Conference on Signal Processing,1994,1:34~44
    [69]Lee H, Park R H. Comments on an optimal threshold scheme for image segmentation. IEEE Transactions on Systems, Man and Cybernetics,1990,20(3):741~742
    [70]Liu J Z, Li W Q. The automatic thresholding of gray-level pictures via two-dimensional Otsu method, Acta Automatica Sinica,1993,19(1):101~105
    [71]Ng H F. Automatic thresholding for defect detection. Pattern Recognition Letters,2006, 27(14):1644~1649
    [72]Lloyd D E. Automatic target classification using moment invariant of image shapes. Technical Report, RAE IDN AW126, Farnborough, UK,1985
    [73]Jawahar C V, Biswas P K, Ray A K. Investigations on fuzzy thresholding based on fuzzy clustering. Pattern Recognition,1997,30(10):1605~1613
    [74]Sahoo P, Wilkins C, Yeager J. Threshold selection using Renyi's entropy. Pattern Recognition,1997,30(1):71~84
    [75]Li C H, Lee C K. Minimum cross entropy thresholding. Pattern Recognition,1993,26(4): 617~625
    [76]Li C H, Tam P K S. An iterative algorithm for minimum cross entropy thresholding. Pattern Recognition Letters,1998,19(8):771~776
    [77]Brink A D, Pendock N E. Minimum cross-entropy threshold selection. Pattern Recognition,1996,29(1):179~188
    [78]Wong A K C, Sahoo P K. A gray-level threshold selection method based on maximum entropy principle. IEEE Transactions on Systems, Man and Cybernetics,1989,19(4): 866~871
    [79]Albuquerque M P, Esquef I A, Mello A R G. Image thresholding using Tsallis entropy. Pattern Recognition Letters,2004,25(9):1059~1065
    [80]Shanbhag A G. Utilization of information measure as a means of image thresholding. Computer Vision, Graphics, and Image Processing,1994,56(5):414~419
    [81]Cheng H D, Chen Y H, Sun Y. A novel fuzzy entropy approach to image enhancement and thresholding. Signal Processing,1999,75(3):277~301
    [82]Kaufmann A. Introduction to the theory of fuzzy subsets:fundamental theoretical elements. Vol.1, Academic Press, New York,1975
    [83]Liu D, Jiang Z, Feng H. A novel fuzzy classification entropy approach to image thresholding. Pattern Recognition Letters,2006,27(16):1968~1975
    [84]Karl P. Philosophical transactions of the royal society of London. Series A,1894,185: 71~110
    [85]Cheng S C, Tsai W H. A neural network implementation of moment-preserving technique and its application to thresholding. IEEE Transactions on Computer,1993,42:501~507
    [86]Hertz L, Schafer R W. Multilevel thresholding using edge matching. Computer Vision, Graphics, and Image Processing,1988,44(3):279~295
    [87]Murthy C A, Pal S K. Fuzzy thresholding:mathematical framework, bound functions and weighted moving average technique. Pattern Recognition Letters,1990,11(3):197~206
    [88]Huang L K, Wang M J. Image thresholding by minimizing the measures of fuzziness. Pattern Recognition,1995,28(1):41~51
    [89]Yager R R. On the measure of fuzziness and negation. Part I:Membership in the unit interval. International Journal of General Systems,1979,5:221~229
    [90]Ramar K, Arumugam S, Sivanandam S N, Ganesan L, Manimegalai D. Quantitative fuzzy measures for threshold selection. Pattern Recognition Letters,2000,21(1):1-7
    [91]Pikaz A, Averbuch A. Digital image thresholding based on topological stable state. Pattern Recognition,1996,29(5):829~843
    [92]Leung C K, Lam F K. Maximum segmented image information thresholding. Graphical Models and Image Processing,1998,60(1):57~76
    [93]Solihin Y, Leedham C G. Integral ratio:A new class of global thresholding techniques for handwriting images. IEEE Transactions on Pattern Analysis and Machine Intelligence,1999, 21(8):761~768
    [94]Aviad Z, Lozinskii E. Semantic thresholding. Pattern Recognition Letters,1987,5(5): 321~328
    [95]Gallo G, Spinello S. Thresholding and fast iso-contour extraction with fuzzy arithmetic. Pattern Recognition Letters,2000,21(1):31~44
    [96]Chanda B, Majumder D D. A note on the use of graylevel co-occurrence matrix in threshold selection. Signal Processing,1988,15(2):149~167
    [97]Pal N R, Pal S K. Entropic thresholding. Signal Processing,1989,16(2):97~108
    [98]Lie W N. An efficient threshold-evaluation algorithm for image segmentation based on spatial graylevel co-occurrences. Signal Processing,1993,33(1):121~126
    [99]Chang C, Chen K, Wang J, Althouse M L G. A relative entropy-based approach to image thresholding. Pattern Recognition,1994,27(9):1275~1289
    [100]Lu W, Songde M A, Lu H. An effective entropic thresholding for ultrasonic imaging. Proceedings of 14th International Conference on Pattern Recognition,1998,2:15221524
    [101]Li L, Gong R, Chen W. Gray level image thresholding based on fisher linear projection of two-dimensional histogram. Pattern Recognition,1997,30(5):743~749
    [102]Brink A D. Thresholding of digital images using two-dimensional entropies. Pattern Recognition,1992,25(8):803~808
    [103]吴一全,潘喆,吴文怡.二维直方图区域斜分阈值分割及快速递推算法.通信学报,2008,29(4):77~83
    [104]Cheng H D, Chen Y H. Fuzzy partition of two-dimensional histogram and its application to thresholding. Pattern Recognition,1999,32(5):825~843
    [105]Brink A D. Minimum spatial entropy threshold selection. IEE Proceedings of Vision, Image and Signal Processing,1995,142(3):128~132
    [106]Niblack W. An introduction to image processing, Prentice-Hall, Englewood Cliffs, NJ, 1986,115~116
    [107]Sauvola J, Pietikainen M. Adaptive document image binarization. Pattern Recognition, 2000,33(2):225~236
    [108]White J M, Rohrer G D. Image thresholding for optical character recognition and other applications requiring character image extraction. IBM Journal of Research Dev.1983,27(4): 400~411
    [109]Bernsen J. Dynamic thresholding of gray level images. Proceedings of International Conference on Pattern Recognition,1986,1251~1255
    [110]Yanowitz S D, Bruckstein A M. A new method for image segmentation. Computer Vision, Graphics, and Image Processing,1989,46(1):82~95
    [111]Chan F H Y, Lam F K, Zhu H. Adaptive thresholding by variational method. IEEE Transactions on Image Processing,1998,7(3):468~473
    [112]Wonho O, Lindquist B. Image thresholding by indicator kriging. IEEE Transactions on Pattern Analysis and Machine Intelligence,1999,21(7):590~602
    [113]Chang F, Liang K H, Tan T M, Hwan W L. Binarization of document images using Hadamard multiresolution analysis. Proceedings of 5th International Conference on Document Analysis and Recognition,1999,157~160
    [114]Pavlidis T. Threshold selection using second derivatives of the gray-scale image. Proceedings of 2th International Conference on Document Analysis and Recognition,1993, 274~277
    [115]Yasnoff W A, Mui J K, Bacus J W. Error measures for scene segmentation. Pattern Recognition,1977,9(4):217~231
    [116]Hu Q, Hou Z, Nowinski W L. Supervised range-constrained thresholding. IEEE Transactions on Image Processing,2006,15 (1):228~240
    [117]Fawcett T. An introduction to ROC analysis. Pattern Recognition Letters,2006,27 (8): 861~874
    [118]Wang Z, Bovik A C, Sheikh H R, Simoncelli E P. Image quality assessment:from error visibility to structural similarity. IEEE transactions on Image Processing,2004,13(4): 600~612
    [119]Martens J B, Meesters L. Image dissimilarity. Signal Processing,1998,70(3):155~176
    [120]VQEG. Final report from the video quality experts group on the validation of objective models of video quality assessment, http://www.vqeg.org/,2000
    [121]Wang Z, Bovik A C. A universal image quality index. IEEE Signal Processing Letters, 2002,9(3):81~84
    [122]Yin P Y, Chen L H. A fast iterative scheme for multilevel thresholding methods. Signal Processing,1997,60(3):305~313
    [123]Hammouche K, Diaf M, Siarry P. A multilevel automatic thresholding method based on a genetic algorithm for a fast image segmentation. Computer Vision and Image Understanding, 2008,109(2):163~175
    [124]Yuksel M E, Borlu M. Accurate segmentation of dermoscopic images by image thresholding based on type-2 fuzzy logic. IEEE Transactions on Fuzzy Systems,2009,17(4): 976~982
    [125]Tao W, Jin H, Zhang Y, Liu L, Wang D. Image thresholding using graph cuts. IEEE Transactions on Systems, Man and Cybernetics, Part A,2008,38(5):118.1~1195
    [126]Saha P K, Udupa J K. Optimum image thresholding via class uncertainty and region homogeneity. IEEE Transactions on Pattern Analysis and Machine Intelligence,2001,23(7): 689~706
    [127]Horng M H. A multilevel image thresholding using the honey bee mating optimization. Applied Mathematics and Computation,2010,215(9):3302~3310
    [128]Sund T, Eilertsen K. An algorithm for fast adaptive binarization with applications in radiotherapy imaging. IEEE Transactions on Medical Imaging,2003,22(1):22~28
    [129]Bhanu B. Automatic target recognition:state of the art survey. IEEE Transactions on Aerospace and Electronic Systems,1986,22(4):364~379
    [130]Huang S, Ahmadi M, Ahmed M A S. A hidden markov model-based character extraction method. Pattern Recognition,2008,41 (9):2890~2900
    [131]Hou Z, Hu Q, Nowinski W L. On minimum variance thresholding. Pattern Recognition Letters,2006,27(14):1732~1743
    [132]Wang S, Chung F, Xiong F. A novel image thresholding method based on parzen window estimate. Pattern Recognition,2008,41 (1):117~129
    [133]Mohar B. Isoperimetric numbers of graphs. Journal of Combinatorial Theory, Series B, 1989,47(3):274~291
    [134]Dodziuk J. Difference equations, isoperimetric inequality and transience of certain random walks. Transactions on the American Mathematical Society,1984,284(2):787~794
    [135]陶文兵,金海.一种新的基于图谱理论的图像阈值分割方法.计算机学报,2007,30(1):110~119
    [136]Arora S, Acharya J, Verma A, Panigrahi P K. Multilevel thresholding for image segmentation through a fast statistical recursive algorithm. Pattern Recognition Letters,2008, 29(2):119~125
    [137]Scott D W. On optimal and data-based histograms. Biometrika,1979,66(3):605~610
    [138]White S, Smyth P. A spectral clustering approach to finding communities in graphs. In SIAM International Conference on Data Mining,2005
    [139]梁学军,乐宁.基于光强加权梯度算子的图像过渡区算法.图像识别与自动化,2001.1:4~7
    [140]闫成新,桑农,张天序,曾坤.基于局部复杂度的图像过渡区提取与分割.红外与毫米波学报,2005,24(4):312~316
    [141]Zhang C, Zhang J, Chen H. Local fuzzy entropy-based transition region extraction and thresholding. International Journal of Information Technology,2006,12(6):19~25
    [142]曹占辉,张科,李言俊.局部模糊复杂度的图像过渡区域提取算法.火力与指挥控制,2008,33(1):25~27
    [143]Groenewald A M, Barnard E, Botha E C. Related approaches to gradient-based thresholding. Pattern Recognition Letters,1993,14(7):567~572
    [144]Shannon C E. A mathematical theory of communication. Bell System Technical Journal 27:379~423,1948
    [145]章毓晋.过渡区和图象分割.电子学报,1996,24(1):12~17

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