BS ISO-IEC 29158-2020 Information technology. Automatic identification and data capture techniques.原版完整文件

BSISO/IEC29158:2020

BSIStandardsPublication

Informationtechnology—Automatic

identificationanddatacapturetechniques—DirectPartMark(DPM)QualityGuideline

bsi.

BSISO/IEC29158:2020BRITISHSTANDARD

Nationalforeword

ThisBritishStandardistheUKimplementationofISO/IEC29158:2020.ItsupersedesPDISO/IECTR29158:2011,whichiswithdrawn.

TheUKparticipationinitspreparationwasentrustedtoTechnical

CommitteeIST/34,Automaticidentificationanddatacapturetechniques.

Alistoforganizationsrepresentedonthiscommitteecanbeobtainedonrequesttoitscommitteemanager.

Thispublicationdoesnotpurporttoincludeallthenecessaryprovisionsofacontract.Usersareresponsibleforitscorrectapplication.

CTheBritishStandardsInstitution2020PublishedbyBSIStandardsLimited2020

ISBN9780580930485ICS35.040.50

CompliancewithaBritishStandardcannotconferimmunityfromlegalobligations.

ThisBritishStandardwaspublishedundertheauthorityoftheStandardsPolicyandStrategyCommitteeon31December2020.

Amendments/corrigendaissuedsincepublication

DateTextaffected

BSISO/IEC29158:2020

INTERNATIONALISO/IEC

STANDARD29158

Firstedition2020-12

Informationtechnology—Automaticidentificationanddatacapture

techniques—DirectPartMark(DPM)QualityGuideline

TechnologiesdeI'information—Techniquesautomatiques

d'identificationetdecapturededonnées—Lignedirectricedequalitédumarquagedirectsurpièce(DPM)

ReferencenumberISO/IEC29158:2020(E)

OISO/IEC2020

BSISO/IEC29158:2020ISO/IEC29158:2020(E)

COPYRIGHTPROTECTEDDOCUMENT

OISO/IEC2020

Alrightsreserved.Unlessotherwisespecified,orrequiredinthecontextofitsimplementation,nopartofthispublicationmaybereproducedorutilizedotherwiseinanyformorbyanymeans,electronicormechanical,includingphotocopying,orpostingontheinternetoranintranet,withoutpriorwrittenpermission.PermissioncanberequestedfromeitherISOattheaddressbeloworISO'smemberbodyinthecountryoftherequester.

ISOcopyrightoffice

CP401·Ch.deBlandonnet8CH-1214Vernier,Geneva

Phone:+41227490111Email:copyright@Website:

PublishedinSwitzerland

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ContentsPage

Foreword V

Introduction vi

1Scope 1

2Normativereferences 1

3Termsanddefinitions 1

4Symbolsandabbreviatedterms 2

5Overviewofmethodology 2

5.1ProcessdifferencesfromISO/IEC15415 2

5.2Lighting3

5.3Tiltedcoaxiallightingandcameraposition(TCL) 3

6Obtainingtheimage 4

6.1Camerapositionandsymbolorientation 4

6.1.1Symbolplacement 4

6.1.2Camerapositionina90°cameraanglesetup 5

6.1.3TCLsetup 5

6.2Lightingenvironments 5

6.2.1General 5

6.2.2Perpendicularcoaxial(90) 5

6.2.3Diffuseoff-axis(D) 5

6.2.4Fourdirection(angleQ) 5

6.2.5Twodirection(angleT) 5

6.2.6Onedirection(angleS)) 6

6.2.7TCLSetup 6

6.3Imagefocus 6

6.4Depthoffield 6

6.5Systemresponseadjustmentandreflectancecalibration 6

7Verifyingasymbol 7

7.1Initialimagereflectance 7

7.1.1General 7

7.1.2Initializeaperturesize 7

7.1.3Createinitialhistogram 7

7.1.4Computemean 7

7.1.5Optimizeimage 7

7.2Obtainingthetestimage 7

7.2.1Matrixsymbologies7

7.2.2Binarizeimage 7

7.3ApplyReferenceDecodeAlgorithm 8

7.3.1General 8

7.3.2Repeatifnecessary 8

7.3.3Continueuntilend 8

7.4Finalimageadjustment 8

7.4.1General 8

7.4.2Determinegrid-pointreflectancewithtwoapertures 8

7.4.3Createagrid-pointhistogram 8

7.4.4Measuremeanlight(M[) 8

7.4.5Recordparameters 8

7.4.6Createbinarizedimagesforthesymbologyreferencedecode 9

7.4.7Decode 9

8Determinecontrastparameters 9

8.1Initializeaperturesize 9

8.2Calculatecellcontrast(CC) 9

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8.3Calculatecellmodulemodulation(CMOD) 9

8.4Calculateminimumreflectance(Rtarget) 9

9Grading 10

9.1Cellcontrast(CC) 10

9.2Minimumreflectance(Rtarget) 10

9.3Cellmodulation(CM) 11

9.4Fixedpatterndamage(FPD) 11

9.5Finalgrade 12

10Communicatinggraderequirementsandresults 12

10.1General 12

10.2Communicationofapplicationrequirements 12

10.3Communicatingfromverifiertoapplication 12

10.4Communicatingtheuseofaproprietarydecode 12

AnnexA(normative)Thresholddeterminationmethod 14

AnnexB(informative)Evaluationofimageatvirtual90°camerapositionfromrealtilted

cameraposition 18

AnnexC(normative)ContinuousgradingforISO/IEC15415parameters 2

AnnexD(normative)Dotconnectingalgorithm 27

AnnexE(informative)Communicatingthegrade 29

AnnexF(informative)CrossreferencetoISO/IEC15415 32

Bibliography 3

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Foreword

ISO(theInternationalOrganizationforStandardization)andIEC(theInternationalElectrotechnicalCommission)formthespecializedsystemforworldwidestandardization.NationalbodiesthataremembersofISOorIECparticipateinthedevelopmentofInternationalStandardsthroughtechnicalcommitteesestablishedbytherespectiveorganizationtodealwithparticularfieldsoftechnicalactivity.ISOandIECtechnicalcommitteescollaborateinfieldsofmutualinterest.Otherinternationalorganizations,governmentalandnon-governmental,inliaisonwithISOandIEC,alsotakepartinthework.

TheproceduresusedtodevelopthisdocumentandthoseintendedforitsfurthermaintenancearedescribedintheISO/IECDirectives,Part1.Inparticular,thedifferentapprovalcriterianeededforthedifferenttypesofdocumentshouldbenoted.ThisdocumentwasdraftedinaccordancewiththeeditorialrulesoftheISO/IECDirectives,Part2(see/directives).

Attentionisdrawntothepossibilitythatsomeoftheelementsofthisdocumentmaybethesubjectofpatentrights.ISOandIECshallnotbeheldresponsibleforidentifyinganyorallsuchpatentrights.DetailsofanypatentrightsidentifiedduringthedevelopmentofthedocumentwillbeintheIntroductionand/orontheISOlistofpatentdeclarationsreceived(see/patents)ortheIEClistofpatentdeclarationsreceived(seehttps://patents.iec.c).

Anytradenameusedinthisdocumentisinformationgivenfortheconvenienceofusersanddoesnotconstituteanendorsement.

Foranexplanationofthevoluntarynatureofstandards,themeaningofISOspecifictermsandexpressionsrelatedtoconformityassessment,aswellasinformationaboutISO'sadherencetotheWorldTradeOrganization(WTO)principlesintheTechnicalBarrierstoTrade(TBT),see/iso/foreword.html.

ThisdocumentwaspreparedbyJointTechnicalCommitteeISO/TCJTC1,InformationTechnology,SubcommitteeSC31,Automaticidentificationanddatacapturetechniques.

ThisfirsteditioncancelsandreplacesISO/IECTR29158:2011,whichhasbeentechnicallyrevised.Themainchangescomparedtothepreviouseditionareasfollows:

—inclusionofcontinuousgrading;

—expandedgradinglevelsforminimumreflectance(Rtarget);一inclusionofatiltedlightingandcameraposition;

—reorganizedproposedlightingoptions.

Anyfeedbackorquestionsonthisdocumentshouldbedirectedtotheuser'snationalstandardsbody.Acompletelistingofthesebodiescanbefoundat/members.html.

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V

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Introduction

DirectPartMarking(DPM)isatechnologywhereby,generally,anitemisphysicallyalteredtoproducetwodifferentsurfaceconditions.Thisalterationcanbeaccomplishedbyvariousmeansincluding,butnotlimitedto,dotpeen,lasermark,inkjetting,andelectro-chemicaletch.Theareaofthealterationiscalled"themark."Theareathatincludesthemarkandbackgroundasawhole,whencontainingapatterndefinedbyabarcodesymbologyspecification,iscalled"asymbol."

Whenlightilluminatesasymbol,itreflectsdifferentlydependingonwhetheritimpingesonthebackgroundofthepartoronthephysicalalteration.Inmostnon-DPMbarcodescanningenvironments,lightisreflectedoffasmoothsurfacethathasbeencolouredtoproducetwodifferentdiffusereflectedstates.TheDPMenvironmentgenerallydoesnotfitthismodelbecausethetwodifferentreflectedstatesdependonatleastoneofthestateshavingmaterialorientedtothelightingsuchthattheangleofincidenceisequaltotheangleofreflection.Sometimesthematerialsoorientedproducesaspecular(mirrorlike)reflectancethatresultsinasignalthatisordersofmagnitudegreaterthanthesignalfromdiffusereflectance.

Inaddition,fromthescannerpoint-of-view,somemarkingandprintingmethodsgeneratedotsandarenotcapableofproducingsmoothlines.ThisisimportantforsymbologiessuchasDataMatrix,whichisspecifiedtocontainsmoothcontinuouslines,butcanbemarkedwithdisconnecteddotsinDPMapplications.

Currentspecificationsformatrixsymbologiesandtwo-dimensionalprintqualityarenotexactlysuitedtoreadingsituationsthathaveeitherspecularreflectionorunconnecteddotsorboth.Additionally,symbologiesspecifiedtoconsistofsmoothcontinuouslinesmayappearwithunconnecteddots.ThisisintendedtoactasabridgebetweentheexistingspecificationsandtheDPMenvironmentinordertoprovideastandardizedimage-basedmeasurementmethodforDPMthatispredictiveofscannerperformance.

Aswithallsymbologyandqualitystandards,itistheresponsibilityoftheapplicationtodefinetheappropriateparametersofthisguidelineforuseinconjunctionwithaparticularapplication.

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Informationtechnology—Automaticidentificationand

datacapturetechniques—DirectPartMark(DPM)QualityGuideline

1Scope

Thisdocumentisanengineeringdocumentintendedforverifiermanufacturersandapplicationspecificationdevelopers.

ThisdocumentdescribesmodificationstothesymbolqualitymethodologydefinedinISO/IEC15415andasymbologyspecification.Itdefinesalternativeilluminationconditions,somenewtermsandparameters,modificationstothemeasurementandsubsequentgradingofcertainparametersandthereportingofthegradingresults.

Thisdocumentwasdevelopedtoassessthesymbolqualityofdirectmarkedparts,wherethemarkisapplieddirectlytothesurfaceoftheitemandthereadingdeviceisatwo-dimensionalimager.

Whenapplicationspecificationsallow,thismethodisalsopotentiallyapplicabletosymbolsproducedbyothermethods.Thisisappropriatewhendirectpartmarked(DPM)symbolsandnon-DPMsymbolsarebeingscannedinthesamescanningenvironment.ThesymbolgradeisreportedasaDPMgraderatherthanasanISO/IEC15415grade.

2Normativereferences

Thefollowingdocumentsarereferredtointhetextinsuchawaythatsomeoralloftheircontentconstitutesrequirementsofthisdocument.Fordatedreferences,onlytheeditioncitedapplies.Forundatedreferences,thelatesteditionofthereferenceddocument(includinganyamendments)applies.

ISO/IEC15415,Informationtechnology—Automaticidentificationanddatacapturetechniques—Barcodesymbolprintqualitytestspecification—Two-dimensionalsymbols

ISO/IEC19762,Informationtechnology—Automaticidentificationanddatacapture(AIDC)techniques—Harmonizedvocabulary

3Termsanddefinitions

Forthepurposesofthisdocument,thetermsanddefinitionsgiveninISO/IEC19762andISO/IEC15415andthefollowingapply.

ISOandIECmaintainterminologicaldatabasesforuseinstandardizationatthefollowingaddresses:—ISOOnlinebrowsingplatform:availableat

/obp

—IECElectropedia:availableat

/

3.1

referencesymbol

high-contrastprintedcalibrationcardforwhichresultsaretraceablebacktonationalorinternationalstandardsandforwhichthesuppliersuppliesacalibrationcertificate

3.2

stick

linesegmentcomprisedofimagepixelsthatisusedtoconnectareasofthesamecolourthatareneartoeachother

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4Symbolsandabbreviatedterms

CMcellmodulation

CCcellcontrast

CMODcellmodulemodulation

FPDfixedpatterndamage

Mpmeanofthegrid-centrepointhistogramofthedarkelementsMLmeanofthegrid-centrepointhistogramofthelightelements

MLcalmeanofthelightlobefromahistogramofthecalibratedstandard

MLtargetmeanofthelightlobefromthefinalgrid-pointhistogramofthesymbolundertest

Rcalreportedreflectancevalue,Rmax,fromacalibrationstandard

Rtargetmeasuredpercentreflectanceofthelightelementsofthesymbolundertestrelativetothe

calibratedstandard

NOTERtargetisgradedandreportedastheparameternamed“MinimumReflectance”.

SRcalsystemresponseparameters(suchasexposureand/orgain)usedtocreateanimageofthe

calibrationstandard

SRtargetsystemresponseparameters(suchasexposureand/orgain)usedtocreateanimageofthe

symbolundertest

T₁thresholdcreatedusingahistogramofthedefinedgreyscalepixelvaluesinacirculararea

20timestheaperturesizeindiameter,centredontheimagecentreusingthealgorithmdefinedinAnnexA

T₂thresholdcreatedusingthehistogramofthereferencegreyscaleimagepixelvaluesateachintersectionpointofthegridusingthemethoddefinedinAnnexA

TmincurrentminimumthresholdinthecalculationoftheoptimalthresholdaccordingAnnexA

TmaxcurrentmaximumthresholdinthecalculationoftheoptimalthresholdaccordingAnnexA

TCLtiltedcoaxiallightingandcameraposition

5Overviewofmethodology

5.1ProcessdifferencesfromISO/IEC15415

Allparametersinthesymbologyandprintqualityspecificationsapplyexceptfor:—adifferentmethodforsettingtheimagecontrast;

一adifferentmethodforcreatingthebinaryimage;一anewmethodforchoosingtheaperturesize;

—animagepre-processmethodologyforjoiningdisconnectedmodulesinasymbol(whereapplicable);

—adifferentprocessfordeterminingthemodulationandreflectancemarginparameterrenamedcellmodulation(CM);

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—adifferentprocessfordeterminingthesymbolcontrastparameterwhichhasbeenrenamedcellcontrast(CC);

—adifferentprocessforcomputingFPD;

—Anewparametercalledminimumreflectance(Rtarget).

Axialnonuniformity,gridnonuniformityandunusederrorcorrectionareappliedwiththeircontinuousgradinggradesasdefinedinAnnexC,solongasISO/IEC15415doesnotprovideinformationoncontinuousgradingfortheseparameters.If/whenISO/IEC15415doesprovidecontinuousgradingontheseparameters,thatinformationwillbeused.Thisdocumentexplainshowtobothspecifyandreportqualitygradesinamannercomplementaryto,yetdistinctfrom,themethodinISO/IEC15415.

NOTEAnnexFgivesacrossreferencecomparisonofthisdocumenttoISO/IEC15415.

5.2Lighting

Lightingenvironmentsshallbereportedaccordingto6.2and10.2.Thelightingenvironment(s)shallbeselectedbytheapplicationstandardinconsiderationofthepropertiesofthemarkandtherequirementsofthereadingequipmentandenvironmentoftheapplication.

5.3Tiltedcoaxiallightingandcameraposition(TCL)

TCLisusefulforDPMapplicationsthatuseageometricalmarkwhichispeened,drilledorcarvedintoasurface.Readingcameraandunidirectionalilluminationarelocatedatacoaxialpositionwithaknownfixedtiltangleandobjectrotationangleandposition.

Toreaddot-peenedcodes,therearemultiplereadingsetupspossible.Thisdocumentdefinesseveralcameraandlightingsetupsinordertoaddressvariousdotpeengeometries.

ThisspecificTCLenvironmentisfocussingonthesystemresponseofthemark(e.g.theimageacamerasees).SAEStandardAS9132[2]takesadifferentapproachtospecifythemarkgeometry.

Figure1illustratesthesetup.Theessentialparameteristhecamerareadingangle.Typicalcamerareadinganglesinclude30°,45°or60°inrelationtotheplaneofthemark.

NOTE1ThecameraangleisdefinedinacompatiblewaytothelightingangleofISO/IEC15415:2011,Figure3.NOTE2Withinthedotpeenindustry,itiscommontospecifythestylusanglewhichistwicethecameraanglegiveninFigure1.

NOTE3Inpractice,thecondition"coaxiallighting"maybeimplementedbyanapproximatesetuplikeahighdistancering.Thelightangletoleranceof±3°shouldberespected.

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Key

ccameraandcoaxiallighting

mlightbeaminmarkisreflectedtocamera0lightbeamoutsidemarkisreflectedawayαcamerareadingangle

ppeenedmarkMmarkedobject

Figure1—Tiltedcoaxiallightingandcamerasetup

Thissetupisreferencedbytheabbreviation"TCL"inthefollowingtext.

Itisnotfeasibletogradethissetupwithacameraangleof90°.Theresultwillnotbesignificantforthisapplication,asotherfeaturesofthemarkedobjectaremeasured.

Notethatageneral-purposeverifierdevicemaynotcoverthisapplication,asitrequiresaspecialconstruction.

6Obtainingtheimage

6.1Camerapositionandsymbolorientation

6.1.1Symbolplacement

Cameratoobjectpositionisdescribedinthissubclause.Bydefault,thehorizontalandverticalaxisofthesymbolareparalleltoalineformedbytheedgeoftheimagesensorwithin±3°(i.e.nominallynorotation).Thissymbolorientationshouldbemaintainedunlessanapplicationspecificationrequiresorallowsadifferentorientation.Anapplicationspecificationmayspecifyadifferentsymbolrotation.Sincethesymbolrotationisdeterminedafterdecoding,theactualrotationangleshouldbereportedsothatthesetupcanbereproducedeasily.Inapplicationsinwhichtherotationangleisspecified,therotationangleshallbereportedtoconfirmconformancetospecifiedrequirements.

Thepartisplacedsuchthatthesymbolisinthecentreofthefieldofview.

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6.1.2Camerapositionina90°cameraanglesetup

Thecameraispositionedsuchthattheplaneoftheimagesensorisparalleltotheplaneofthesymbolarea.Thisisidenticaltoa90°cameraangle.

6.1.3TCLsetup

WithintheTCLsetup,cameraandsymbolpositiondiffersinthefollowingpoints.—Thecameraispositionedinthecameraangledefinedbytheapplication.

—Therawimageisgeometricallytransformedtocorrespondtoatestimagewithavirtualcamerapositionwitha90°cameraangle,asdescribedinAnnexB.

—Thesymbolrotationangleneedstobespecifiedbytheapplicationandshallberespectedby±5°.

6.2Lightingenvironments

6.2.1General

Thelightingenvironmentisspecifiedbytheapplication.Thisshallincludeadirectionspecifieroranangleorboth.TheformatisanextensionoftheanglespecifierusedinISO/IEC15415.Severalexamplesaregiveninthefollowingsubclauses.

6.2.2Perpendicularcoaxial(90)

Thesymbolisilluminatedwithdiffuselightsuchthatthespecularreflectionfromtheentirefieldofviewisnominallyuniform.

6.2.3Diffuseoff-axis(D)

Adiffuselyreflectingdomeisilluminatedfrombelowsothatthereflectedlightfallsnon-directionallyonthepartanddoesnotcastdefinedshadows.Thisiscommonlyusedforreadingcurvedparts.TheanglespecifiershallbeD.

Thislightingisalsocalleddomelighting.

6.2.4Fourdirection(angleQ)

Lightisaimedatthepartatthegivenangle±3°fromtheplaneofthesurfaceofthesymbolfromfoursidessuchthatthelinesdescribingthecentreofthebeamsfromopposingpairsoflightsareco-planarandtheplanesatrightanglestoeachother.Onelightingplaneisalignedtobeparalleltothelineformedbyahorizontaledgeoftheimagesensortowithin±5°.Thelightingshallilluminatetheentiresymbolareawithnominallyuniformenergy.Theanglespecifiershallbeangle"Q".

EXAMPLE45Q(angleequalto45°)or30Q(angleequalto30°).

6.2.5Twodirection(angleT)

Lightisaimedatthepartatthegivenangle±3°fromtwosides.Thelightmaybeincidentfromeitherofthetwopossibleorientationswithrespecttothesymbol.Thelightingplaneisalignedtobeparalleltothelineformedbyoneedgeoftheimagesensortowithin±5°.Thelightingshallilluminatetheentiresymbolareawithnominallyuniformenergy.Theanglespecifiershallbeangle"T".

EXAMPLE45T(angleequalto45°)or30T(angleequalto30°).

Sincetherearetwopossibleorientationsinthissetup(aboveandbelow,andleftandright)theparticularorientationactuallyusedshouldbereported.Thereportingmethodmaybetoindicatethelocationofthelightswithrespecttothesymbolsuchas“north-south”whenthelightisincidentfrom

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aboveandbelowthenatural“top”and“bottom”ofasymbol.Theorientationofasymbolisknownafterdecodingandrelatedtothenormalorientationofasymbolasspecifiedinitssymbologyspecification(e.g.aDataMatrixsymbol'snaturalorientationhasthesolidbordersonleftandbottom,andforQRcodethenormalorientationhasfinderpatternsintheupperleft,lowerleftandupperrightcornersbutnotlowerrightcorner.)

6.2.6Onedirection(angleS)

Lightisaimedatthepartatthegivenangle±3°fromoneside.Thelightmaybeincidentfromanyofthefourpossibleorientationswithrespecttothesymbol.Theplaneperpendiculartothesymbolsurfacecontainingthecentreofthebeamisalignedtobeparalleltothelineformedbyoneedgeoftheimagesensortowithin±5°.Thelightingshallilluminatetheentiresymbolareawithnominallyuniformenergy.TheanglespecifiershallbeangleS.Sincetherearefourpossibleorientationsinthissetup,theparticularorientationoftheincidentilluminationshouldbereportedbasedonthesymbolorientationdeterminedafterdecoding,withrespecttothesymbol'snormalorientation(see6.2.5).Forexample,ifasymbolisupsidedown,andtheilluminationisincidentfrombelowthesymbol,suchthattheilluminationisactuallyorientedtowardthe“top”ofthesymbol,thentheincidentlightshouldbereportedas“North”.

EXAMPLE45S(angleequalto45°)or30S(angleequalto30°).

6.2.7TCLSetup

TCLsetupusescoaxiallightatthecamerareadingangle.Lightisaimedatthecamerareadinganglewithatoleranceof±3°.Thelightingshallilluminatetheentiresymbolareawithnominallyuniformenergy.

Typicallightingsetupsare30°(30CS),45°(45CS)or60°(60CS).Theanglespecificationhasanadded"C"toindicatethecoaxialcameraposition.

NOTEAcameraangleof90°isnotaTCLsetup(nottilted).Inconsequence,aspecificationof"(90CS)"isnot

allowed.

6.3Imagefocus

Thecameraisadjustedsuchthatthesymbolisinbestfocus.

6.4Depthoffield

Non-planarsurfacesoraTCLsetupmayrequireadepthoffieldrange.TheconditiongiveninISO/IEC15415:2015,7.3.3shouldbefulfilledforthewholedepthoffie