数字图像处理 外文翻译 外文文献 英文文献 数字图像处理

DIGITALIMAGEPROCESSING1INTRODUCTIONMANYOPERATORSHAVEBEENPROPOSEDFORPRESENTINGACONNECTEDCOMPONENTNADIGITALIMAGEBYAREDUCEDAMOUNTOFDATAORSIMPLIEDSHAPEINGENERALWEHAVETOSTATETHATTHEDEVELOPMENT,CHOICEANDMODI_CATIONOFSUCHALGORITHMSINPRACTICALAPPLICATIONSAREDOMAINANDTASKDEPENDENT,ANDTHEREISNOBESTMETHOD“HOWEVER,ITISINTERESTINGTONOTETHATTHEREARESEVERALEQUIVALENCESBETWEENPUBLISHEDMETHODSANDNOTIONS,ANDCHARACTERIZINGSUCHEQUIVALENCESORDI_ERENCESSHOULDBEUSEFULTOCATEGORIZETHEBROADDIVERSITYOFPUBLISHEDMETHODSFORSKELETONIZATIONDISCUSSINGEQUIVALENCESISAMAININTENTIONOFTHISREPORT11CATEGORIESOFMETHODSONECLASSOFSHAPEREDUCTIONOPERATORSISBASEDONDISTANCETRANSFORMSADISTANCESKELETONISASUBSETOFPOINTSOFAGIVENCOMPONENTSUCHTHATEVERYPOINTOFTHISSUBSETREPRESENTSTHECENTEROFAMAXIMALDISCLABELEDWITHTHERADIUSOFTHISDISCCONTAINEDINTHEGIVENCOMPONENTASANEXAMPLEINTHIS_RSTCLASSOFOPERATORS,THISREPORTDISCUSSESONEMETHODFORCALCULATINGADISTANCESKELETONUSINGTHED4DISTANCEFUNCTIONWHICHISAPPROPRIATETODIGITIZEDPICTURESASECONDCLASSOFOPERATORSPRODUCESMEDIANORCENTERLINESOFTHEDIGITALOBJECTINANONITERATIVEWAYNORMALLYSUCHOPERATORSLOCATECRITICALPOINTS_RST,ANDCALCULATEASPECI_EDPATHTHROUGHTHEOBJECTBYCONNECTINGTHESEPOINTSTHETHIRDCLASSOFOPERATORSISCHARACTERIZEDBYITERATIVETHINNINGHISTORICALLY,LISTING10USEDALREADYIN1862THETERMLINEARSKELETONFORTHERESULTOFACONTINUOUSDEFORMATIONOFTHEFRONTIEROFACONNECTEDSUBSETOFAEUCLIDEANSPACEWITHOUTCHANGINGTHECONNECTIVITYOFTHEORIGINALSET,UNTILONLYASETOFLINESANDPOINTSREMAINSMANYALGORITHMSINIMAGEANALYSISAREBASEDONTHISGENERALCONCEPTOFTHINNINGTHEGOALISACALCULATIONOFCHARACTERISTICPROPERTIESOFDIGITALOBJECTSWHICHARENOTRELATEDTOSIZEORQUANTITYMETHODSSHOULDBEINDEPENDENTFROMTHEPOSITIONOFASETINTHEPLANEORSPACE,GRIDRESOLUTIONFORDIGITIZINGTHISSETORTHESHAPECOMPLEXITYOFTHEGIVENSETINTHELITERATURETHETERMTHINNING“ISNOTUSEDINAUNIQUEINTERPRETATIONBESIDESTHATITALWAYSDENOTESACONNECTIVITYPRESERVINGREDUCTIONOPERATIONAPPLIEDTODIGITALIMAGES,INVOLVINGITERATIONSOFTRANSFORMATIONSOFSPECI_EDCONTOURPOINTSINTOBACKGROUNDPOINTSASUBSETQ_IOFOBJECTPOINTSISREDUCEDBYADE_NEDSETDINONEITERATION,ANDTHERESULTQ0QNDBECOMESQFORTHENEXTITERATIONTOPOLOGYPRESERVINGSKELETONIZATIONISASPECIALCASEOFTHINNINGRESULTINGINACONNECTEDSETOFDIGITALARCSORCURVESADIGITALCURVEISAPATHPP0P1P2PNQSUCHTHATPIISANEIGHBOROFPI1,1_I_N,ANDPQADIGITALCURVEISCALLEDSIMPLEIFEACHPOINTPIHASEXACTLYTWONEIGHBORSINTHISCURVEADIGITALARCISASUBSETOFADIGITALCURVESUCHTHATP6QAPOINTOFADIGITALARCWHICHHASEXACTLYONENEIGHBORISCALLEDANENDPOINTOFTHISARCWITHINTHISTHIRDCLASSOFOPERATORSTHINNINGALGORITHMSWEMAYCLASSIFYWITHRESPECTTOALGORITHMICSTRATEGIESINDIVIDUALPIXELSAREEITHERREMOVEDINASEQUENTIALORDERORINPARALLELFOREXAMPLE,THEOFTENCITEDALGORITHMBYHILDITCH5ISANITERATIVEPROCESSOFTESTINGANDDELETINGCONTOURPIXELSSEQUENTIALLYINSTANDARDRASTERSCANORDERANOTHERSEQUENTIALALGORITHMBYPAVLIDIS12USESTHEDE_NITIONOFMULTIPLEPOINTSANDPROCEEDSBYCONTOURFOLLOWINGEXAMPLESOFPARALLELALGORITHMSINTHISTHIRDCLASSAREREDUCTIONOPERATORSWHICHTRANSFORMCONTOURPOINTSINTOBACKGROUNDPOINTSDI_ERENCESBETWEENTHESEPARALLELALGORITHMSARETYPICALLYDE_NEDBYTESTSIMPLEMENTEDTOENSURECONNECTEDNESSINALOCALNEIGHBORHOODTHENOTIONOFASIMPLEPOINTISOFBASICIMPORTANCEFORTHINNINGANDITWILLBESHOWNINTHISREPORTTHATDI_ERENTDE_NITIONSOFSIMPLEPOINTSAREACTUALLYEQUIVALENTSEVERALPUBLICATIONSCHARACTERIZEPROPERTIESOFASETDOFPOINTSTOBETURNEDFROMOBJECTPOINTSTOBACKGROUNDPOINTSTOENSURETHATCONNECTIVITYOFOBJECTANDBACKGROUNDREMAINUNCHANGEDTHEREPORTDISCUSSESSOMEOFTHESEPROPERTIESINORDERTOJUSTIFYPARALLELTHINNINGALGORITHMS12BASICSTHEUSEDNOTATIONFOLLOWS17ADIGITALIMAGEIISAFUNCTIONDE_NEDONADISCRETESETC,WHICHISCALLEDTHECARRIEROFTHEIMAGETHEELEMENTSOFCAREGRIDPOINTSORGRIDCELLS,ANDTHEELEMENTSPIPOFANIMAGEAREPIXELS2DCASEORVOXELS3DCASETHERANGEOFASCALARIMAGEISF0GMAXGWITHGMAX_1THERANGEOFABINARYIMAGEISF01GWEONLYUSEBINARYIMAGESIINTHISREPORTLETHIIBETHESETOFALLPIXELLOCATIONSWITHVALUE1,IEHIII11THEIMAGECARRIERISDE_NEDONANORTHOGONALGRIDIN2DOR3DSPACETHEREARETWOOPTIONSUSINGTHEGRIDCELLMODELA2DPIXELLOCATIONPISACLOSEDSQUARE2CELLINTHEEUCLIDEANPLANEANDA3DPIXELLOCATIONISACLOSEDCUBE3CELLINTHEEUCLIDEANSPACE,WHEREEDGESAREOFLENGTH1ANDPARALLELTOTHECOORDINATEAXES,ANDCENTERSHAVEINTEGERCOORDINATESASASECONDOPTION,USINGTHEGRIDPOINTMODELA2DOR3DPIXELLOCATIONISAGRIDPOINTTWOPIXELLOCATIONSPANDQINTHEGRIDCELLMODELARECALLED0ADJACENTI_P6QANDTHEYSHAREATLEASTONEVERTEXWHICHISA0CELLNOTETHATTHISSPECI_ES8ADJACENCYIN2DOR26ADJACENCYIN3DIFTHEGRIDPOINTMODELISUSEDTWOPIXELLOCATIONSPANDQINTHEGRIDCELLMODELARECALLED1ADJACENTI_P6QANDTHEYSHAREATLEASTONEEDGEWHICHISA1CELLNOTETHATTHISSPECI_ES4ADJACENCYIN2DOR18ADJACENCYIN3DIFTHEGRIDPOINTMODELISUSEDFINALLY,TWO3DPIXELLOCATIONSPANDQINTHEGRIDCELLMODELARECALLED2ADJACENTI_P6QANDTHEYSHAREATLEASTONEFACEWHICHISA2CELLNOTETHATTHISSPECI_ES6ADJACENCYIFTHEGRIDPOINTMODELISUSEDANYOFTHESEADJACENCYRELATIONSA_,_2F012461826G,ISIRREEXIVEANDSYMMETRICONANIMAGECARRIERCTHE_NEIGHBORHOODN_POFAPIXELLOCATIONPINCLUDESPANDITS_ADJACENTPIXELLOCATIONSCOORDINATESOF2DGRIDPOINTSAREDENOTEDBYIJ,WITH1_I_NAND1_J_MIJAREINTEGERSANDNMARETHENUMBERSOFROWSANDCOLUMNSOFCIN3DWEUSEINTEGERCOORDINATESIJKBASEDO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法一类形状减少算子是基于距离变换的。一个距离骨架是一个子集点，某一特定的组成部分，例如，每点子，这代表了该中心的一个最大光盘（标记半径这片光碟）载于特定的组成部分。作为一个例子，在这类算子，本报告讨论了一个计算方法距离骨架使用的D4距离函数，这是适当的数字化图片。第二类算子产生的中位数或中心线数字对象在一个非迭代的方式。通常这样的算子找到临界点，并计算出特殊路径通过对象连接这些点。第三类是算子的特点是迭代细化。从历史上看，用已经在1862年任期线性骨架为结果连续变形的前一个连接子一欧氏空间没有改变的连通原来的设置，直到只有一套线和点仍然存在。许多算法在图像分析是在此基础上的一般概念的细化。目标是计算特性的数字对象，其中不相关的大小或数量。方法应是独立的立场从一组，在平面或空间，网格的决议（数字化这套）或形状复杂该给定。在文献中的任期间是没有用在一个独特的解释，此外，它始终是指连接维护减少运作，适用于数字图像，所涉及的迭代变革的特殊轮廓点到背景点。一个字集Q_I的对象点是减少了设置，在一迭代和Q0的结果QND成为Q报表下次迭代。拓扑维护骨架是一个特殊的案件细化，导致连接的一套数码化的圆弧或曲线。数字曲线的道路是一条在PP0P1P2的QNQ等,PI是PI1的近邻，1_I_N和PQ,数字曲线是所谓的简单元素，如果每点PI有准确的两个邻域在这曲线。数码弧是一个子集数字曲线，如P6Q一点的数码弧其中，正是一邻居是所谓的一归宿，这电弧。在这第三类算子（细化算法），我们可能分类方面的算法策略个别像素要么拆除在一个顺序或平行进行。举例来说，经常提到的算法HILDITCH是一个迭代的过程中的测试和删去的轮廓像素，按顺序在标准光栅扫描秩序。另一种序贯算法PAVLIDIS使用的多点和收益由轮廓下列的的例子，并行算法在这第三类是减少算子，其中变换轮廓点到背景点。这些并行算法通常是测试实施连通性，以确保在目标连接和内部数据没有改变。概念一简单点是基本的重要性细化且它将会显示在这报告说，简单点，其实是相等的。若干出版物的特点性能是一套署点（可从对象点到背景点转变）去确定目标和背景的连贯性仍然没变报告讨论了一些性质是为了证明平行细算法的正确性12基础所用符号如下17。数字图像I是一个功能离散集C，即所谓的载体的形象。要素的C是网格点或网格细胞和分子性（PI（P）一个图像像素（2维）或体素（三维案件）。范围的形象是F0GMAXG与GMAX_1。范围二进制的形象是F0，我们只使用在此报告的二进制图像。让它成为一套所有像素的位置与价值1。形象载体是对一正交网格在二维或三维空间。有两种选择使用网格细胞模型的二维像素位置，P是一个封闭的广场（2细胞）在欧氏平面和三维像素的位置是封闭立方体（3细胞），在欧氏空间，那里边的长度为1和平行于坐标轴，中心有整数坐标。作为一个第二个选项，使用网格点模型一二维或三维像素的位置是一个网格点。两个像素的位置P和Q在网格中的细胞模型是所谓的0毗邻I_P6Q和他们分享至少有一个顶点（这是一个零细胞）。两个三维像素的位置P和Q在网格中的细胞模型是所谓的毗邻I_P6Q和他们分享至少有一个优势（这是一细胞）。注意如果格点模型是用这邻接在二维或邻接在三维。最后，两个像素的三维位置P和Q在网格中的细胞模型被称为2毗邻I_P6Q和他们分享至少有一个面对的（这是一个2细胞）。请注意，如果格点模型是用这邻接的。任何这些邻接关系12461826是和对称对一的形象，N_（P）条像素位置P包括P和其_相邻像素的位置。坐标的二维网格点是指由（IJ）中，与1_IN和1_J_MJ是整数和NM是多少行和列正在3维中使用整数坐标（IJK）段。基于邻域的关系，我们连通如常2点PQ2C是有关N_I_有一个序列点，PP0P1P2PNQ近邻，在此序列无论是在M或全部在补M的一个子集M_C的形象承运人是所谓的_连接I_M，是不是空洞和所有点，在M都成对设置M组成的一个子集S的C是一个极大值,连接子S的研究连通性数码影像已在15介绍了。因此，任何一套集合组成了若干组件。在案件该网格的细胞模型，一个组成部分，是联接的封闭空间（二维情况下）或关闭的立方体（三维案件）。边界2细胞是联接在其4细胞和5细胞的。3细胞是连接在其6接口。为实际目的是易于对数字图像中使用的临近操作的（所谓的本地操作）。价值在P2架C，在转化的形象是基于像素值在I在P2C和其立即邻域在N_P。2非迭代算法非迭代算法提供子组件在特殊扫描命令测试连接保存在一个迭代次数。在本节中，我们只用网格点模型。21距离算法BLUM3提出了骨骼的代表是一组对称点。在一个封闭的子欧氏平面一点P是被称为对称I_。至少有2点存在于边界与平等的距离页每对称点，相关的最大光盘是在这一套世界上最大的光盘。一套对称点，每一个标记半径相关最大的光碟，构成了骨架的一套。这个想法提交的一个组成部分，数字图像作为一个距离骨架的基础上，计算一个距离各点在一个连通子米_C至补子。本地最高的子代表一距离骨架。在15D4类距离是如下特殊的距离，D4（PQ）的从点P点Q，P6Q是最小的积极整数N，如存在着一种序列具有鲜明的网格点，P值P0，P2PNQ是4近邻，PI1，1_I_N如果P值Q之间的距离是趋向于为零