Eci Altona Test Suite v2 Technical2 Documentation Eng 3

1Altona Test Suite 2.0 Technical 2

20112012, European Color Initiative, www.eci.org

Altona Test Suite 2.0 Technical 2

July 2012



Background When version 1.0 of the Altona Test Suite was released, it addressed the all new PDF/X standard most importantly how to find out whether output from a PDF/X file was cor-rect or not. The Altona Test Suite turned into a powerful tool for many participants of the print production food chain: tofindoutwhetheragivenproductwould

live up to their expectations for users to ensure their entire workflow

could and did handle PDF/X files correctly for associations to develop best practice

guidelines

The first international PDF/X standard was released in 2001 (PDF/X-1a, followed byPDF/X-3 in 2002). PDF/X has since turned into thepredominantfileexchange format in theprintingindustry.Adecadelaterwefindour-selves in a situation, where substantial newfeatures have been introduced into the PDFformat. A new part of the PDF/X standard has been released in 2008: PDF/X-4, finally sup-portingtransparency,OpenTypefonts,option-alcontent(akalayers),pagesizesbeyond5by5meters,JPEG2000compressionandmore.Itscompanionstandard,PDF/X-5,wasdevelopedinthesametime,standardizingincompleteorpartial file exchanges, targeting very specificneedsinnichemarkets.

Some of the features defined in newer ver-sions of the PDF syntax and standardized inPDF/X-4haveproventobemoredemandingfor implementers than others: Transparency introduced a completely

new dimension of complexity any com-binationofobjecttype,colorspace,blendmode, opacity, nesting of transparencygroupsandsoforthcanbeused,andactu-ally isusedbyadventurousanddemand-ing designers who in turn are driven bytheirinsatiablecustomerslongingforevermoreenticingdesigns.Quiteanumberofdevelopers found it less than trivial to cope with the challenges of such added com-plexity, both in terms of performance aswell as correctness of the produced results.

Optional content (often referred to as layers)hasbeenaroundinthePDFformatforanumberofyearsbutsofarisonlysup-portedbyasmallnumberofPDFvendors.ItallowsthecreationofPDFsforwhichausercanswitchbetweenviews, forexam-ple between different language versionsof a text document, or betweendifferentinstances of a PDF for packaging, whereeach instance reflectsadifferentflavororcolor of a product package, while all in-stances share the common graphic ele-ments.Inaddition,somepagecontentcanbeturnedonoroffonanasneededbasislikemeasurementinformation,cutlines,identifyinginformationorhumanreadableinstructionsinapackagingfile.

TheOpenType font format an industry standardthathasalsobeenadoptedasanISOstandardthatusesthetermOpenFontFormat (ISO/IEC 14496-22) constitutes aconsolidatedfontformatbuildingonboththe PostScript and TrueType font formats, fullysupportingUnicodeaswellasallow-ingintelligentlyforeventhemostcomplexscriptslikeThaiorclassicalMongolian.

JPEG2000(ISO15444)isanextremelyflex-ible compression format for continuoustoneimages.ItisnottobemixedupwithJPEG, as it uses a completelydifferent ar-chitecture and algorithms. While JPEG isalways lossy, JPEG2000 can be used in alossless way, on average offering bettercompression than ZIP. In addition it sup-portsawidevarietyofcolorspacesandbitdepths. Finally, it also provides options to decodeimagesprogressivelyveryconve-nientforverylargeanddataintensiveim-ages.

Pagesize in PDFs can now easily exceed theoriginalimplementationlimitofrough-ly5by5metersusingaparametercalledUserUnits current implementations sup-portpagesizesofupto381kilometersby381 kilometers.While rarely in use so far,this very specific new feature is a nice ap-proachtomakehandlingoflargepagesiz-esthatarenotuncommoninverylargefor-matprintingmoreelegant.



Quiteanumberofnewfeaturesorexten-sionsof existing features tend tohave a lessdrasticimpactbutmighteasilybeoverlooked,like the support for version 4 ICC profiles orNChannelcolor.

Notonlyisthedevelopmentworktosup-portthefeaturesintroducedbetweenPDF/X-1a and PDF/X-3 on one side and PDF/X-4 onthe other side far from trivial it is also a chal-lengetodoqualityassuranceandtesting.Ven-dors tend to have their own set of carefully de-velpedtestfiles,buteventheymightnothavethoroughlydesignedtestfilesforeachaspectofaPDF/X-4implementation.Nottospeakoftheir customers how do they find out wheth-erthePDF/X-4supportclaimedbyavendorisactuallyasextensiveandaccurateassuggest-ed by the vendors product marketing? Lastbut not least therewill be a number of sce-narioswheretwoexpertsmaydisagreeaboutwhatthecorrectresultshouldlooklike.

In addition to targeting features intro-duced in PDF/X-4, the Altona Test Suite 2.0TechnicalPagealsoextendsanumberofteststhat would have already applied to PDF/X-1a and PDF/X-3, for example more extensive cov-erageforsmoothshadesorPostScriptandTru-eType fonts thanwasavailable inAltonaTestSuite1.0through1.2.

The Technical Page of the Altona TestSuite 2.0 aims to address the needs of all par-ties involved in the production and process-ing of PDF/X-4 files. The test page containsa sequence of patcheswhere each patch al-lowsa relativelyeasyandstraightforwardas-sessment of the quality of output generat-edfromaPDF/X-4file.AllpatcheshavebeendevelopedbymembersoftheEuropeanCol-orInitiativeallofthemexpertsfamiliarwithPDF standards development, and with a sol-idbackground in softwaredevelopmentandprint production over a period of aboutthreeyears.Vendorshavehad theoption forabouteighteenmonths toaccessabetaver-sionofthetestpagebeforeitwasreleasedtothepublic.

WhoshouldusetheAltonaTestSuite2.0TechnicalPage,andhow?Vendors: It is expected thatanyvendorde-velopingtoolsorsolutionsthatprocessorout-putPDF/X-4filesinanywaywillfindtheAlto-naTestSuite2.0TechnicalPageusefulfor: qualityassurancefortherenderingresults

ofaRIPs,printer,proofingsystemoroutputon screen

quality assurance for products that pro-cessPDF/X-4,forexamplecolorconverters,inkoptimizers,ortoolsthatassemblecom-pleteorpartialpages

qualityassuranceforPDFconsumingtools,like for examplePDF import in authoringapplications

Output service providers:anyorganiza-tionofferingprintingservicesinthebroadestsense,thatdoesacceptPDF/X-4fileswillfindthetestpageusefultodeterminetowhichde-gree theirworkflowprocesses thosePDF/X-4filescorrectly,andtoidentifyprocessingstepsthat provide less than perfect handling ofPDF/X-4 files.Very often all tools involved inthe processing of PDF/X-4 files fully supportPDF/X-4, but are either not configured cor-rectly, or are combined intoaprocessing se-quence that is not PDF/X-4 compliant. Thusoutput service providers can use the Altona TestSuite2.0TechnicalPageto test the complete workflow processing

chain testindividualcomponentsforsuitability checktheconfigurationforacomponent trackconformanceofasetuponanongo-

ingbasis throughregularly repeatedcon-trol output, for example in the form of a weeklyprocessvalidation

Producers of print ready PDF files: it maysoundasifonlyorganizationsorpersonsprocessingPDF/X-4filehaveaneedforade-centPDF/X-4testpage.Rathertothecontrary:a producer of print ready PDF/X-4 files willneedameanstojudgetheappearancetobe



expected from a compliant output system. In order to achieve this, already the author-ingapplicationmustsupportPDF/X-4correct-ly,oratleastaverificationtoollikeageneralpurpose PDF viewer that correctly simulates theexpectedoutputbasedonthePDF/X-4filethatisgoingtobesenttoaprinter.

Repurposing: While the PDF format is of-ten considered as a final form format, where the only remaining processing steps are dis-play or creation of printed output, reality in the communication industry at large teach-es us that a substantial portion of PDF filesoriginally intended just for a singleprint runtendstobereusedandrepurposedinnumer-ousways.Whetherafileforgravureprintingistobesenttoadigitalprintingdevice,ortobeusedforonlineadvertisingoronatabletPCnothinkableoptionexiststhatisnotactuallyusedatsomepointbyquiteanumberofusers.

Whereappearanceofcontentorbrandcol-ors is important to those initiating the com-munication, it usually becomes an absoluterequirementtogettherenderedoutputrightregardless of what the ultimate communi-cation channel is.Though a smartphonewilltypicallynot render anon-trivial PDF/X-4filecorrectly, precautions need to be taken thatwhatever is sent to such a smartphone is re-flecting the originally created appearance ascorrectlyaspossible.

Overall structure TheTechnicalpageconsistsofanoverallstruc-tureaslistedbelow: 15 patches that reflect real world use of

PDF/X-4features,eachidentifiedbyasin-gleuppercasecharacter(AthroughR)

6 blocks to systematically test the maintransparency parameters, identified by asingleuppercasecharacter(SthroughZ):

blendmodes blendcolorspaces sourcecolorspaces pagelabelwithcolorconversionindicators pageframewithdifferentvariantsproduc-

ingauniformgrayvisualappearance.Inadditiontobeingcontainedinthetestpage,thepatchesAthroughR,ablockconsistingof

patches S throughZ, aswell as the label arealso provided individually, with each of these containedonitsowninaseparatepage.

PatchA

Patchdesign,practicalrelevancePatchAreflectsaverycommonuseof trans-parency:dropshadows.Inadditionitaddress-es the potential impact of the layout and de-sign applications Transparency FlattenerPresets (resolution settings in particular) onthe output quality. These settings often de-finetheimageresolutionofthesocalledsoftmaskswhicharecreatedduringthePDFcre-ation toachieve the transparenteffect (here:drop shadow).

Regardless of the transparency handlingbytheoutputdevice(transparencyflatteningwithhigherresolutionortransparencyrender-ing on e.g. the Adobe PDF Print Engine) thesoftmasksresolutionmaylimitthequalityun-der certain circumstances. For that reason it is important, that the creator of the PDF chooses theFlattenerPresetsproperly.

Technical parametersAllobjectcolorsaredefinedasprocesscolors.Three lines of text are placed on top of an im-ageandagraybackground.Thedropshadow(100%blackink,usingblendmodeMultiply,withanopacityof75%)isdividedintotwosec-tions to demonstrate the potential impact of thetransparencyprocessingsettings.Thepart

A



onthelefthandsidehasasignificantlyhigherresolutionthanthethepartontherighthandside (200 ppi). The two drop shadow sections touch each other in the middle of the patch (undertheletterspandh).

Exampleforincorrectoutput

PatchB

Patchdesign,practicalrelevancePatchBaddressespossibleissuesfromthein-teraction of color conversions with process-ingtransparencyorwithtransparencyflatten-ing,inparticulartheconversionofspotcolors(here: orange colored text objects) and RGBimagestoprocesscolors.Digitalprintingpro-cesses often require the conversion of spotcolors to process colors.

Technical parametersThetextcolorisaspotcolornamedOrange.The drop shadow is defined in the same way as inpatchA(100%blackink,usingblendmodeMultiply,withanopacityof75%).Theback-

groundimageisdividedintotwosections:thelowerleftsectionisanRGBimage(eciRGBv2)while thepart in theupper right isaDevice-CMYK image. The color properties assignedto the RGB image have been used to createtheCMYK image inPhotoshop: rendering in-tentperceptual,targetprofileISOCoatedv2300%(ECI).

ExamplesforincorrectoutputIf the process color conversion of thespot color takes place after transparen-cy flattening, white boxesmay occur under-neath the drop shadow (upper example).

Adistinctcolordifferencebetweentheup-per right and lower left section of the back-ground imagewould indicatecolormanage-ment deficiencies (lower example).

B



PatchC

Patchdesign,practicalrelevanceThis patch focuses on a property determin-ing the interaction of objectswithin a trans-parencygroup:Thegroupmaybeknockoutornon-knockout,whichdetermineswhethereachof theobjectswithin its stack are com-posited with one another and then into the groups backdrop, or only with the groupsbackdrop.

Technical parametersTheuppertwolinesoftextbelongtoatrans-parencygroupsettonon-knockout.Asshownin the reference image (lower half of thepatch), the transparency effect (blendmodeMultiply) results inadarker color in the in-tersectingpartsofthetwotextlines.Thelow-ertwolinesaresettoknockoutandthereforeshall be rendered without a color differenceintheintersectingparts.Bothgroupsinteractwiththebackdrop(rectanglefilledwithalightred process color).


PatchD

Patchdesign,practicalrelevancePatch D is designed to systematically assessthe color management capabilities in con-junction with transparency handling. Prop-ercolorrenderingrequiresthatallpropertiessuchas sourcecolorprofile, rendering intentand targetcolorprofile (here thedestinationprofile in theOutputIntent)arehonored.TherespectivetestobjectsaretakenfromtheVisu-alpageoftheAltonaTestSuitev1.1.

C

D



Technical parametersThe patch contains three lines of objects,eachlineconsistingofthefivecolormanage-mentpatchesfromtheVisualpageoftheAl-tonaTestSuitev1.1.Theupperrowstranspar-encysetting isblendmodeNormalwithanopacity of 70%. The middle row is set to the blendmodeColorDodgewithanopacityof100%,while thebottomrowsblendmode isLuminancewithanopacityof100%.Allob-jectssharethesamegraybackground(Device-CMYK0.32/0.32/0.32/0.32).

ExpectedoutputNote:Foraquickcheckthefollowinghintmayhelp:thefirsttwocolormanagementsquaresper row (from left to right) shall be coloredidentically in all four sections. The sections are indicatedbysmallicons.Thethreesquaresattherighthandsideshallshowadistinctcolordifferencealongtheedgesindicatedbysmalllinesunderneaththesquares.

Examplesforincorrectoutput

PatchE

Patchdesign,practicalrelevanceThis patch is designed to detect possible is-sues with fine image details in conjunctionwithtransparencyprocessingorflattening.

Technical parametersAcurveshaped,white (DeviceCMYK0/0/0/0)objectisplacedontopofanimage,usingtheblendmodeNormalwithanopacityof42%.Inthelowerpartoftheimagecrispblacklinesand red checker boards have been added.Eachoftheblacklinesiseitherone,two,threeor fourpixelswide. Each small squareof theredcheckerboardissizedatexactlyonepixel.

Expectedoutput

Enlargedviewoffineimagedetails

E




Inadequate image compression settings ap-plied during transparency flattening maycause disturbing artifacts, e.g. ragged linesalongtheblackstrokes.

PatchF

Patchdesign,practicalrelevanceProperfonthandlingisachallengewhenevertext is affectedby transparency flatteningortrapping.PDF/X-4extendsthenumberofvalidfont types allowed in previous PDF/X version byaddingsupportforType1andTrueTypefla-voredOpenTypefonts.Inadditionissuesmayoccur with text converted to outlines.

Technical parametersThe fonts used in this patch comprise all rel-evant font types such as PostScript Type 1, TrueType and OpenType, the latter in bothTrueType and PostScript flavored versions.The fonts chosen for the patch cover differ-entscriptssuchasLatin,AsianorHebrewandArabic typefaces.Besides that, thecharacterswere selected to address issues that may oc-curwithdifferentfontencodingsandcertaincharacterssuchasligatures,aswellasdiacriticmarksliketheFrenchaccent aigu.Theglyphsof thetwowordsat thebottomof thepatchhave been converted to outlines in AdobePhotoshop (Muchas) and Adobe InDesign(Gracias).

PatchG

Patchdesign,practicalrelevanceThe patch combines smooth shade effectswithtransparencyeffects,usingcombinationsof device independent and device dependent colordefinitionsandblendingspaces.Design-erswillinsomecasesplaywithbothkindsofeffectsuntiltheyarriveatanappearancethatistotheir liking.Ascanbeseenalreadyfromcomparingthesamecharactersintheleftver-ticalcharactersequenceandtherightverticalcharactersequence,smallbutsometimessig-nificant differences in appearance occur de-pendingonexactlyhowtheeffectsareused.

F

G



Technical parametersBackground:verywidedashedlinealternatingbetween10%Kand70%K.

Foreground:CharactersA,B,CandD,inMyri-adBold48pt,filledwithaxialsmoothshadingin the form of Type 1 patterns:

Each smooth shade is built using WideGamutRGBICCbasedcolorspace

eachcharactersitsontoptwoyellowandbluesquares,thesesquaresarecoloredus-ingLab

thecharactersontopofthesesquaresusetransparency

A:Difference100% B:Luminosity60% C:Colour100% D:Exclusion75% each character is grouped together with

theyellowandbluesquareunderneathit,wheresomegroupsuseanisolatedgroup,whereas others dont, and for some thegroup is isolatedand forothers it is non-isolated.

the verticalA-B-C-D sequenceon the leftuses DeviceCMYK as blending space forthetransparencygroup,whereastheverti-calA-B-C-DsequenceontherightusestheWideGamutRGBICCbasedcolorspaceas itsblendingspace.

Expectedoutput

10




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PatchH

Patchdesign,practicalrelevanceThe patch is intended to test proper render-ingofalltypesofgradients,includingthesev-en smooth shade types defined in the PDF language,conventionalPostScript1stylegra-dientbuiltbyvectorelementsaswellaspix-el based gradients. Common smooth shadetypes like axial and radial shades usually arerendered properly, while more complex types suchasthesocalledIllustratorgradientmeshare sometimes not processed correctly. Anoth-er issuearegradientscontainingaspotcolorwhereoverprintingandtransparencyproper-tiesmaynotbehandledproperly.

Technical parametersThe smooth shades are arranged from topto bottom in this sequence: function-basedshading(type1),axialshading(type2), radialshading (type 3), free-form Gouraud-shadedtrianglemesh (type4), lattice-formGouraud-shaded triangle mesh (type 5), Coons patchmesh(type6)andtensor-productpatchmesh(type7),betterknownasIllustratorgradientmesh.

Theblacklinesmarkvariantsofgradientsrep-resenting different approaches in the designstage. The cyan to yellow gradient contains(from top to bottom): a smooth shade (axialshading),aconventionalvectorgradientandapixelgradient.Thefourspotcolorgradientscomprise axial shadingsusing the spot colorOrangeindifferentways(fromtoptobottom):spotcolorOrangeonly,DeviceN(blackandOr-ange),andtwoaxialshadingscreatedbytwopiecesplacedontopofeachother:Orangeonblack (transparency, blend mode Multiplywithanopacityof1.0)andatthebottomOr-angeonblack(settooverprint).


Thefourshadesinthelowersectionshowsig-nificantly less saturated colors compared to thereferenceimage.

Inthiscasethelowermostspotcolorgradientis too lightas theblackgradientunderneaththe orange gradient is ignored (overprintingnot honored).

H

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PatchK

Patchdesign,practicalrelevanceThepatchshowsseveralvariantsthatgobacktocolorizingagrayscale image inanauthor-ingapplication.Designersoftenusedifferentways to achieve the same visual appearance, in this case a violet tint in the upper part and abrownish tint forprintingwithblackandaspotcolorOrange inthe lowerpart.ThePDFpropertiesofthedifferentsectionsdependonthefileformatsofthesourceimagesandhowthegrayscaleimageshavebeencolorized.

Technical parametersIndicatedbyblacklines,thesixsectionsreflectthefollowingwaysofcolorizing: thetopmostsegmentisanLabimagecre-

ated in Photoshop the 2nd segment consists of three gray-

scale imagesplacedontopofeachother,eachcoloreddifferently,andthetoponessettooverprintinInDesign.

the 3rd segment has been created as aduotoneimageinPhotoshop.

The three brownish image segments havebeencreatedinPhotoshopbasedonthesamefileasforthefirstthreesegmentstoreflecttheimpact of the source file type on the PDF prop-erty. The Photoshop source image containstwochannelscolorizedwithprocessblackink(top)andOrangeink(bottom):

the4thsegmentwassavedasaPhotoshopPDF(resultingintwoDeviceNimages),

the5thsegmentwassavedasTIFF(onein-dexedDeviceNimage)

the6thsegmentwassavedas16bitPhoto-shop(PSD)file(oneDeviceNimage).

Eachofthesixsegmentswascreatedasasep-arate file and placed on an InDesign pagewhich was then exported as a PDF file.


K

13



PatchL

Patchdesign,practicalrelevanceThis patch deals with the use of transparen-cyandwhitepageobjects to lightenagivenbackground.

Technical parametersThebackgroundcolorisa100%tonevalueofthe spot colorOrange, partially covered bytwowhitesquares(0%oftherespectivecol-or).Thecolorspaceof theupperrectangle isa separation color space named PANTONEWarmGray 6C using a tint valueof 0.0.ThelowerrectangleiscolorizedwithDeviceCMYK0/0/0/0. Both squares use blendmodeNor-malwithanopacityof50%.

PatchM

Patchdesign,practicalrelevanceThis patch consists of four gray imageswithdifferentcolorproperties,placedon topofagray background. The practical relevance ofthe different color properties are idiosyncra-sies of common design and workflow appli-cationsusedalongtheworkflowfromdesignto output. These applications sometimes tend toalterthecolorspecificationofagivengray-scaleimage.

Technical parametersThe background is a vector object, color-izedwith 22%of processblack (DeviceCMYK0/0/0/22%). The four rectangles in the fore-groundareimagescontaining100%blackpix-elsonlyusingthefollowingcolorspaces(fromtoptobottom): IndexedDeviceCMYK IndexedDeviceN SeparationBlack,and DeviceGray.The imagesblendmode isNormal,withanopacityof50%.

L

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PatchN

Patchdesign,practicalrelevanceThis patch demonstrates two popular meth-odsusedbydesignerstodarkenabackgroundwithagradient.

Technical parametersThebackground is divided into the two sec-tionsgreen(DeviceCMYK40/0/100/0)andor-ange (spot colorOrange).TheblendmodeusedforthetwogradientsisDarken.Thegra-dienton the lefthandside isagrayscale im-age,andthegradientontherighthandsideisasmoothshadingcolorizedwithprocesscolor

black(codedasasinglechannelDeviceNcol-or space).

ExpectedoutputProper renderingputs thegradients into theprocesscolorblackchannelonlyanddoesnotaffectthecolorvaluesofthegreenandorangebackgroundareas.


N

15



PatchP

Patchdesign,practicalrelevanceJPEG2000imagecompressionaswellasabitdepthof16bithavebeenpartofthePDFsyn-taxforanumberofyearsalreadybutareonlyslowly being adopted in day to day produc-tion.While using just JPEG2000 or just a bitdepthof16bitusuallyworkswellinuptodatetechnology,problemsmightoccurwhentheseareusedincombination,ortogetherwithnotso common color spaces, as well as v2 versus v4ICCprofiles.Thispatchusesthesamebaseimageinanumberofbitdepths,colorspaces,anduseofJPEG2000.

Inordertotriggerprocessingforthepatchwithtransparencyinvolved,aMagentacoloredrectanglehasbeenpositionedon topof theimageslices,withanalphavalueof0.0,making itinvisible.

Technical parametersThebase image shows up four times on thepatch(referredtoasA,B,CandDfromtoptobottom),andeachinstanceissubdividedintothreeportions (referred toby 1, 2and3 fromtoptobottom):- A1: 8bit RGB profile (i.e. an RGB profile

where the Red and Green channels havebeenswapped)usingJPEG2000withlossycompression(max.quality)

- A2: 8bit RGB as a v4 ICC profile, usingJPEG2000withlossycompression

- A3: 16bit RGB as a v2 ICC profile, usingJPEG2000withlossycompression

- B1: 16bit RGB as v2 profile, using losslessJPEG2000compression

- B2: 16bit CMYK as a v2 ICC profile, usingJPEG2000withlossycompression

- B3: 16bit CMYK as a v2 ICC profile, usinglosslessJPEG2000compression

- C1: 8bit CMYK as a v4 ICC profile, usingJPEG2000withlossycompression

- C2: 16bit using Lab color space, usingJPEG2000withlossycompression

- C3: 8bit using Lab color space, usingJPEG2000withlossycompression

- D1:8bit IndexedRGBcolorbasedonav2ICCprofile,usingJPEG2000withlossycom-pression

- D2: 16bit gray using a 30% dotgain gray-scale v2 ICC profile, using JPEG2000withlossy compression

- D3: 8bit gray using a 10% dotgain gray-scale v2 ICC profile, using lossless JPEG2000compression

A 1

2

3

B 12

3

C 12

3

D 12

3

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PatchQ

Patchdesign,practicalrelevanceThis patch makes use of patterns, smoothshades, drop shadows, transparency effectsand nested grouping of objects such that insome instances isolated transparencygroupswere created and in other instances not. The patchdoes not follow any specific logic, butrather aims at being anunplanned arrange-ment of graphic objects using all kinds ofgraphic effects available in todays softwareproducts.

Technical parametersArbitrary, partially grouped arrangement ofvectorobjectsmakinguseofvariouseffects.

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PatchRPatchdesign,practicalrelevanceThis patch explores effects that result fromcombiningtransparencywithoverprint.Inad-ditionitmakesuseofoptionalcontent.

Technical parametersThe patch is built according to the informa-tion given in ISO 32000-1 Documentman-agementPortabledocument formatPart1: PDF 1.7, page 744, Figure L.20 Blendingandoverprinting (11.7.4.3,CompatibilitywithOpaqueOverprinting).

Inaddition,thecontentsofthepatchisre-peatedasoptionalcontentsettobenon-visi-ble,wherethisoptionalcontentusesdifferentcoloring,andisoffsetslightlytotherightandto the top.


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BlockwithpatchesS-ZStructure

Patchdesign,practicalrelevanceThe main goal of patches S through Z is tocompletely iterate through certain combina-tions of graphic state parameters that affecttheappearanceoftransparentobjectsdirectlyorindirectly.Thegraphicstateparametersthatarebeingpermutatedare: type of object: on the lowest level, the

patchusesminiature elements consistingofafilledobject,astrokedobject(line)andatext(aminussign);allthreearearrangedtoformarectangularshape;asallarecol-oredusingthesamecolorspace,allthreeshould have identical appearance

colorspace:eachobjecttripleappearsus-ingseveralcolorspaces:

variations of black or gray, using Device-Gray (using a value of 0.45, equivalent to55% black), DeviceCMYK (CMY channelsare zero, K has a value of 25%), Separa-tionBlack(withavalueof45%)andasin-glechannelDeviceNwithBlackasitsonlycolorant(withavalueof60%).

ICC based RGB (1.0/0.0/0.0 RGB taggedwithECI-RGB.V1.0profile)

DeviceCMYK (light pale green, 30%/70%/0%/10%)

spotcolorbymeansofaSeparationcolorspacenamedOrange

16differentblendmodesforthetranspar-ent green object (using a DeviceCMYKfill of 85%/15%/80%/25%) on top of thebackgroundwith theobject triples in thevariouscolorspacesdescribedabove.

3 different blend color spaces Device-CMYK,ICCbasedRGBandICCbasedGray

the3differentblendcolorspacesareusedbyanon-isolated transparencygroup (onthe left) and by an isolated transparencygroup(ontheright).

Theinclusionofallthecombinationsimpliedby this setupmakes it possible to systemati-callycheck that shouldanyof theseoccur inrealworldworkflowstheyarehandledcorrect-ly. It isobviousthat it ismore likely forsomethan for others to happen in real world doc-uments,butonthebackgroundthatmodern

authoring tools enable users to actually cre-ate documents that use arbitrary combina-tionsofobject types, color spaces andothergraphicstateparameters it is tobeexpectedthatanyofthecombinationsfoundinpatchesSthroughZwillonedaybeencounteredinarealworldworkflow.

Inorder tomake it easy to identify incor-rectrenderinginacomplexpatchlikethisone,it was decided to mirror each patch in the form that a correct appearance is shown directly to the right of the actual patch segment.Withtheareasofthevariousobjectstouchingeachother,itisrelativelyeasytospotdeviationsbe-tweenneighboringobjectswheretheyshouldactuallylookthesame.

Eachsegmentofacolumnsbackgroundisacombinationofthreebasicobjects:

stroke fill

text

Each segment of a columns backgrounduses a different color space:

DeviceGray:.45

DeviceCMYK(%):0/0/0/25

SeparationBlack:45%

DeviceNBlack:60%

ICCbasedRGB,ECI-RGB(0..255):255/0/0

DeviceCMYK(%):30/0/70/10

SpotColorOrange:85%

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Averticalgreenbarsettousingtransparencysitsontopofthebackgroundinacolumn

TheverticalgreenbarusesDeviceCMYK(Cyan:0.85,Magenta:0.15,Yellow:0.8,Black:0.25)anda cavalueof0.6(opacity). Ineachofthecol-umns occurrences a different blendmode isusedfortheverticalgreenbar(seebelow).

Eachofthecolumnsismirroredtotheright,suchthatthemirroredpartconsistingofanimagereflectstheexpectedappearance

The left part consists of live objects,whereas the rightpart isan image reflectingthe expected correct appearance for the part on the left.

Note: Due to the nature of this setup, it may eas-ily occur that the left part and the right part of a column do not match exactly. For the purposes of determining correct transparency rendering, common sense should be used to decide wheth-er left and right part are considered to match or not. Small visual differences between left and right part can usually be ignored.

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A4by4matrixofcolumnsiteratesoverthe16blendmodesavailableinPDF

The columns are organized in a 4 by 4matrix, where each column uses a differentblendmodefortheverticalgreenbar.Alloth-erobjectsofacolumnareidenticalacrossall column occurrences.

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Sixblocks iterateoverCMYK,RGBandgrayblendcolorspace,forbothnon-isolatedandforisolatedtransparencygroupsEach 4by 4matrix as awhole usesdifferentcombinations of isolated versus non-isolatedtransparencygroupandblendingcolorspace,fromlefttoright: non-isolated,DeviceCMYK(patchS) non-isolated,ICCbasedRGB(patchT) non-isolated,ICCbasedgray(patchV) isolated,DeviceCMYK(patchW) isolated,ICCbasedRGB(patchX) isolated,ICCbasedgray(patchZ)

PatchesS-Z

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23



Pagelabel

Patchdesign,practicalrelevanceThepagelabel(ontherighthandsideofpatchR)containstwosmallgraysquaresinitslow-er right corner.Thepurposeof theseobjectsis to indicate issues that may arise after color conversionsortheexchangeoftheOutputInt-entprofile(OI).

Thepracticalrelevanceoftheuppersquare(ColorConversionIndicator;lightergray)aree.g.inksavingcolorconversionspriortotrans-parencyrenderingortransparencyflattening.Dependingontheblendmode,colorconver-sions of objects with live transparency maysignificantly affect the visual appearance oftheseobjectsandtheirbackground.

The bottom square (OI Swap Indicator,darkergray)addressestheimportanceoftheOutputIntentprofileforthevisualtransparen-cyeffectofobjectscoloredwithoutputinde-pendentcolors,e.g.RGBimages.

Technical parametersThe Color Conversion Indicator consists ofthreepageobjects.Thebackground isavec-tor element usingDeviceCMYKwith the col-orvalues80/57/67/10.Thebackgroundobjectis fully covered by an object using Device-CMYKwiththecolorvalues0/0/0/66,andthetransparencyblendmodeHardLightwithanopacityof 100%.Thetopmostelement isXshapedusingDeviceCMYKwiththecolorval-

ues 0/0/0/39 the expected appearance fortheareaoutsidetheXshape.

The design of the OI Swap Indicator isalmost identical, except for two differences:Thebackgroundobjectisanimageobjectus-ingtheLabcolorspacewiththecolorvalues60/0/0andanassignedperceptualrenderingintent.ThetransparencyblendmodeisColorBurn.

ExpectedoutputProper rendering results in two uniformlygray colored squares.The upper square, col-orizedwith39%ofprocessblack inkandthelower one colorized with the CMYK values38/30/30/53.


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thesecondsectionisavectorobjectusingDeviceCMYKwiththevalues0/0/0/50.Thissection is the reference for correct process-ingofthefirstsection.

thethirdsectionisavectorobjectusinganICC based RGB color space (eciRGB v2).When properly converted to the destina-tion profile in the OutputIntent, the RGBcolor values 161/162/162 and the render-ingintentRelativeColorimetricresultinagraytonevisuallymatchingthevisualap-pearanceof50%processblackink.

thefourthsectioniscolorizedinthecolorspaceLabwiththevalues63.1/0/0.Prop-erly converted to the output intent profile, honoring the rendering intent RelativeColorimetric, this section again matchesthevisualappearanceof50%processblackink.

Graypageframe

Patchdesign,practicalrelevanceAlong the edges of the page, a 5mm framecreatesagraypageborder.Theborderreflectsdifferent technical ways to achieve a certaingrayappearance.Thetechnicalpropertiesareindicatedon the sectionsof thepage frame.Dependingonthecapabilitiesandsettingsoftheprocessingsoftware,thesectionsmayberendered incorrectly, creating distinct visualdifferences.

Technical parametersFromtheupperleftcornertotheupperrightcorner: the first section consists of a black vec-

torobject(DeviceCMYK0/0/0/100)placedwith50%opacityinNormalblendmodeon top of a white background (Device-CMYK 0/0/0/0). Correct transparency ren-deringcreates50%processinkblack.

ExpectedoutputCorrectrenderingresultsinauniformlycoloredgrayborder.Note:Slightvisualdifferencesbetweentheblack-inkonlyandtheRGBandLabsectionsdonotindi-cateproblemsastheymaybecausedbyroundingeffectsorcolordeviationoftheprinting.

ExamplesforincorrectoutputIn this case, a color conversion using a device link profile with color purity properties (leav-ing solid ink tones untouched) caused the distinct visual difference between the first two sections:

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Evaluatingthetestpage

TheTechnicalPagehasbeendesignedforavi-sualevaluation.Eachpatchissplitintwosec-tions.Onesectioncontainslivecontentwhiletheothersectionprovidesa reference imagewith the expectedcorrect result result. Thereferenceimageismarkedbytwoiconsintheupperleftandlowerrightcorner.

Some patches are split horizontally withthereferenceimageinthelowerpart:

Referenceimagemarkedby -icons in upper leftandlowerrightcorner.

Otherpatchesaresplitverticallywiththeref-erenceimageintherighthandsidedsection.

A

F

ThereferenceimagesofthepatchesSthroughZ are mirrored to the right making it easierto evaluate the result of the live part. Due to space restrictions, the reference images aremarkedby single icons,whichare locatedatthebottomoftherespectivepatch.

As it isnot trivial toprovideacorrect re-sultofthistestpagethatwilllookcorrectun-der all circumstances, and can be achievedinexactlythesamewaybyanoutputdevice,evaluatingoutputofthetestpagemostoftenwillnotbeayesornotest.Rather,undermanycircumstances very small variations will have tobeconsideredacceptableandequivalenttoan officially correct result.

In order to make evaluations as compa-rable as feasible, theevaluation tableon thenextpage is recommended. For carryingoutanevaluationof theoutputof the testpage,theschematicstructureofthetestpageonthepageaftertheevaluationtablemaybeused.

Thefollowingclassificationshouldbeusedfortrackingevaluationresultsinthetable noissues Verysmalldeviations,butstillacceptable Deviationsthatmayormaynotbeaccept-able Clearlyunacceptabledeviations Someorallofthepatchnotrenderedatall

When carrying out an evaluation using theschematicstructure,issuesshouldbeindicat-edbyusingOoranappropriatenumberofX: O-noissues X-Verysmalldeviations,butstillacceptable XX-Deviationsthatmayormaynotbeac-ceptable XXX-Clearlyunacceptabledeviations XXXX-Someorallofthepatchnot rendered at all

Note:Whendoing a visual assessment, sig-nificantcolordifferencesbetweenspotcolorobjectsinthelivepartofapatchversustheirappearanceinthereferenceimagedonotin-dicate an error!

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Altona Test Suite 2.0 Technical Page Evaluation templateAltona Test Suite 2.0 Technical Page Evaluation templateAltona Test Suite 2.0 Technical Page Evaluation templateAltona Test Suite 2.0 Technical Page Evaluation templateAltona Test Suite 2.0 Technical Page Evaluation templateAltona Test Suite 2.0 Technical Page Evaluation templateAltona Test Suite 2.0 Technical Page Evaluation templatePatch No issues Very small

deviations, but still

acceptable

Deviations that may or may not be acceptable

Clearly unacceptable deviations

Some or all of the patch not rendered

at all

Remarks

A

B

C

D

E

F

G

H

K

L

M

N

P

Q

R

S

T

V

W

X

Z

Label

Page frame

:

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A B C DE F G HK L M NP Q R LabelAltona Test Suite 2.0Technical Page

Evaluation template

S T V W X ZPage frame

O no issues X Very small deviations, but still acceptable XX Deviations that may or may not be acceptable XXX Clearly unacceptable deviations XXXX Some or all of the patch not rendered at all

Background 2

WhoshouldusetheAltonaTestSuite2.0TechnicalPage,andhow? 3

Overall structure 4

PatchA 4

PatchB 5

PatchC 6

PatchD 6

PatchE 7

PatchF 8

PatchG 8

PatchH 11

PatchK 12

PatchL 13

PatchM 13

PatchN 14

PatchP 15

PatchQ 16

PatchR 17

BlockwithpatchesS-ZStructure 18

PatchesS-Z 21

Pagelabel 23

Graypageframe 24

Evaluatingthetestpage 25

Visualreference:Separations 28

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Visualreference:Separations

ProcesscolorscmykandspotcolorOrange

Processcolorscmy

SpotcolorOrange

Processcolork

BackgroundWho should use the Altona Test Suite 2.0 Technical Page, and how?Overall structurePatch APatch BPatch C Patch DPatch E Patch F Patch GPatch H Patch KPatch LPatch MPatch NPatch PPatch QPatch RBlock with patches S-Z StructurePatches S - Z Page label Gray page frameEvaluating the test pageVisual reference: Separations

Eci Altona Test Suite v2 Technical2 Documentation Eng 3

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