PDFX

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PDF/X

This text is a first draft and will give you only the basic information needed to create PDF/X compatible documents. More info will be made available at a later date.

First things first. The following parameter should be set for any PDF/X version.

\setupinteraction
  [title=TITLE,
   subtitle=SUBTITLE,
   author=AUTHOR,
   keyword={{KEYWORD1, KEYWORD2}, KEYWORD3}]

Coming to the quite simple interface.

\setupbackend
  [format=valid pdf/x name,
   profile=name.icc,
   intent=name.icc,
   level=compresslevel, % default 3
   file=optional specification file,
   option=always|never]


The two parameter format and intent are sufficient for most cases.

The format parameter simply defines the PDF/X version, while the intent parameter sets the so called output intent.

Currently the following PDF/X versions are supported:

format =

                                               gray  rgb  cmyk  spot  transp. notes
PDF/X-1a:2001  % PDF Version 1.3 (Acrobat 4.x) *          *     *     
PDF/X-1a:2003  % PDF Version 1.4 (Acrobat 5.x) *          *     *     
PDF/X-3:2002   % PDF Version 1.3 (Acrobat 4.x) *     *    *     *
PDF/X-3:2003   % PDF Version 1.4 (Acrobat 5.x) *     *    *     * 
PDF/X-4        % PDF Version 1.6 (Acrobat 7.x) *     *    *     *     *    PDF layers
PDF/X-4p       % PDF Version 1.6 (Acrobat 7.x) *     *    *     *     *    PDF layers; ICC externally supplied
PDF/X-5g       % PDF Version 1.6 (Acrobat 7.x) *     *    *     *     *    PDF layers; graphics can be outside pdf
PDF/X-5n       % PDF Version 1.6 (Acrobat 7.x) *     *    *     *     *    PDF layers; ICC externally supplied
PDF/X-5pg      % PDF Version 1.6 (Acrobat 7.x) *     *    *     *     *    PDF layers; p + g
  • PDF/X-1 uses device dependent colors, i.e. your pictures must be converted into the output color space (gray or CMYK).
  • PDF/X-3+ uses device independent colors, i.e. the color space of your pictures doesn’t matter, but it must be defined by a color profile.
  • It makes no sense to use CMYK pictures with PDF/X-3+, because color conversions between CMYK profiles are more lossy than any RGB-to-CMYK conversion!
  • It makes sense to use PDF/X-1a:2003 for bw printing.
  • Even if they’re allowed in X/4+, don’t use PDF layers for print projects – your printshop will not be able to handle them.

Predefined output intents:

intent =

   Coated FOGRA39 (ISO 12647-2:2004)
   GRACoL2006_Coated1v2.icc
   ISO Coated v2 300% (ECI)
   ISO Coated v2 (ECI)
   ISOnewspaper26v4
   ISOnewspaper26v4_gr
   ISO Uncoated
   ISO Uncoated Yellowish
   ISO Web Coated
   Japan Color 2001 Coated
   Japan Color 2002 Newspaper
   Japan Web Coated (Ad)
   SNAP 2007
   SWOP2006_Coated3v2.icc
   SWOP2006_Coated5v2.icc
   Uncoated FOGRA29 (ISO 12647-2:2004)
   Web Coated FOGRA28 (ISO 12647-2:2004)
   PSR_LWC_PLUS_V2_PT
   PSR_LWC_STD_V2_PT
   PSR_SC_PLUS_V2_PT
   PSR_SC_STD_V2_PT
   PSRgravureMF

Which one to use?

  • In Europe, use FOGRA profiles.
  • In the USA, use SWOP profiles.
  • In Japan, use Japan profiles.
  • Use Coated for image printing paper.
  • Use Uncoated for natural paper (e.g. "offset").
  • "Web" means "web offset", i.e. big volume printing from a roll of paper (vs. sheet paper).


Some examples:

\setupbackend
  [format=PDF/X-1a:2001,
   intent=SWOP2006_Coated3v2.icc]

or

\setupbackend
  [format=PDF/X-4,
   intent={ISO Coated v2 300\letterpercent\space (ECI)}]


All remaining parameter are kind of special.

profile sets the ICC based default color space profile (option for color management); this setting is document wide and currently only one profile per color space is allowed

level sets the PDF compress level (values of 0..9 are allowed). Normally no need to change the default value.

option=always|never

   always: force embedding of the output intent profile (useful only in case of PDF/X-1a)
   never : don't embed the output intent profile; no useful practise

file name of an external file with predefined color profiles

ICC profiles

The predefined color profiles can be found in .../<context-path>/colors/icc/context/colorprofiles.xml|.lua.

This list contains the profiles recommended by the GWG (Ghent PDF Workgroup) in 2008, the set of profiles bundled with ghostscript and three test only profiles from the ICC (International Color Consortium).

Ghent PDF Workgroup (GWG) recommendations:

There are a few contradictions to the PDF/X standards (by PDF Association) to assure a better quality, see the article by Stephan Jaeggi.

Nearly all predefined ICC profiles are also available in the download section. Output intents are bound to very specific printing conditions (which vary worldwide), so it’s very likely that you only need one or two ICC profiles (and not all of them). Therefore the profile ZIPs come in 'localized' versions.

GWG recommend ICC profiles (complete) (Europe) (India) (Japan) (USA)

Probe profiles (external link): here

Ghostscript profiles: here

All predefined profiles in one zip file


Profile installation:

The profiles are normally stored under

.../<context-path>/colors/icc/profiles

All profiles in the zip archive are already located in the correct sub path, so you only have to unpack them right in your ConTeXt directory (normally texmf-context).

In case you use these profiles also with other software, it is possible to share them with ConTeXt. Simply set the environment variable $OSCOLORDIR to that special software related directory.

E.g. for Adobe Acrobat on Windows Vista this special directory is

C:\Program Files (X86)\Common Files\Adobe\Color\Profiles\Recommended

Store the needed profiles there (without any tex directory) and set $OSCOLORDIR to that path.

All you need now is a final luatools --generate to update the file database.

In case of problems you should add

\enabletrackers[backend.pdfx]

\setupbackend[...

right in front of \setupbackend to get all possible debugging info.

And that's it for the moment...