DigitalImageProcessing

Prof.Dr.Chen

HuiSchoolofISE,ShandongUniversity email:huichen@

Lecture2Introduction

BackgroundDigitalImageRepresentationFundamentalStepsInImageProcessingSystemElementsofDigitalImageProcessingSystemFurtherReadingsOnePictureisworthmorethanathousandwords.Chapter1no.1BackgroundApplications:

Improvementofpictorialinformationforhumaninterpretation.Processingofscenedataforstorage,transmission,andrepresentationforautonomousmachineperception.ScopedefinitionOriginsStateoftheartPrincipalsOverviewofsystemChapter1no.2WhatareDIPandscope?(readbook)DigitalImage:discretebothinspace(x,y)andamplitudefProcessing

bydigitalcomputerPictureelements,imageelement,pels,pixels

Notlimitedtovisualband:wide&varietyfieldofapplicationsNogeneralagreementonthescopeofprocessing,analysis,vision.Input&output,emulatehumanvision(AI).Noclear-cutboundaries.I/Oimages,extractattributes,recognizingobjects.

Suchasanalysisoftext...Chapter1

no.3HistoryEarly1920s,Bartlanecablepicturetransmissionsystem.(specialcharacter,5~15graylevel).Middle1960s,spaceshuttle,aerialandsatelliteimagery.(large-scalecomputer&spaceprogram—DIPconcepts).Others,medicalimage(x-ray,MRI,CT.),geography,archeology,astronomy,physics(high-energyplasmas,electronmicroscope).Machineperception:characterrecognition,industrialmachinevision,militaryrecognizance,matchingfingerprints,etc.Chapter1no.4History(cont.1)Chapter1no.5DigitalimagesHistory(cont.2)Chapter1no.6DigitalimagesHistory(cont.3)Chapter1no.7DigitalimageprocessedbycomputerExamplesChapter1no.8GammarayExamples(cont.1)Chapter1no.8XrayExample(cont.2)Chapter1no.9Visible&InfraredExample(cont.4)Chapter1no.10InfraredExamples(cont.5)Chapter1no.11RadiobandExamples(cont.6)Chapter1no.12UltrasoundExamples(cont.7)Chapter1no.13VisualspectrumDigitalImageRepresentationDefinition:monochromeimage(image),atwo-dimensionallightintensityfunctionf(x,y),point(x,y)spatialcoordinates,fbrightnessvalueofthepoint.DigitalImage:Discretizedbothinspatialcoordinatesandbrightness(matrix,elements,pixels).Imagesizeandthenumberofgraylevelareadvantagestobechosenasintegerpowerof2.(512*512,128!)Chapter1no.14DigitalImageRepresentation(cont.)Chapter1no.15DigitalImageRepresentation(cont.)Chapter1no.15FundamentalStepsInImageProcessingSystemImageacquisition(imagesensor&ADconverter)camera,scanner..Preprocessing(improveimage)

enhancingcontrast,removingnoise…Segmentationpartitionaninputimageintoitsconstituentpart,outputrawpixeldataeitherofboundaryorregion.Representationanddescription(descriptors,featureselection)Recognitionandinterpretation

assignalabeltoanobject,assignmeaningtorecognizedobjects.anexample:automaticreadingoftheaddressonpieceofmail.Chapter1no.16ElementsofDigitalImageProcessingSystemChapter1no.17FurtherReadingSlidesavailableaspdffilesR.C.Gonzalez,R.E.Woods,“DigitalImageProcessing”,2ndedition,Prentice-Hall,2002,Pratt,W.K.,DigitalImageProcessing,3rded.,JohnWiley&Sons,NY.,2001.IEEETransactionsonImageProcessing.IEEETransactionsonPatternAnalysisandMachineIntelligence.ComputerVisionandImageUnderstanding.IEEETransactionsonSignalProcessing.IEEETransactionsonMedicalImaging.Chapter1no.18ElementsofVisualPerceptionStructureofHumanEyeChapter2Elementsofvisualperceptionno.1ImageFormationintheEye

2.55mmElementsofvisualperceptionno.2BrightnessAdaptation

Cannotoperatesucharangesimultaneously.Rather,bychangesinitsoverallsensitivity.Elementsofvisualperceptionno.3BrightnessDiscriminationExperimentBrightnessdiscriminationispooratlowlevelsofillumination.Elementsofvisualperceptionno.4MachBandPatternVisualsystemtendstoundershootorovershootaroundtheboundaryofregionsofdifferentintensities.Elementsofvisualperceptionno.5SimultaneousContrastAregion’sperceivedbrightnessdoesnotdependsimplyonitsintensity.Elementsofvisualperceptionno.6OpticalIllusionsFillinnon_existence/