[XeTeX] Outputing PDFs in CMYK ColorSpace

[Clinton Gormley]

Hi all

> > I'm producing PDFs with xelatex destined to be printed in a newspaper.
> > The printers require the PDFs to use a CMYK colorspace, but I can't find
> > any option to set this.
> 
> You need provide more information about the document: do you have
> external figures/graphics?   What colorspace do they use?  How is
> color used in the document -- just a few specific colors or
> many colors?

Typically, these adverts just use black on white, and include an image
(uploaded by a customer), which could be pretty much anything.

> Is this a 1-shot project or something you will be doing many times?

Many times - it is an online ad booking service.

> The CMYK conversion needs to be checked for your documents.  The OP
> does mention
> some of the quick checks the printer made using Adobe Acrobat that
> found problems
> with the color usage in the document.  Such checking is standard
> practice, and you
> should try to find a way to perform the checks yourself.

Michiel Kamermans suggested "quite a box of tricks", but our servers run
linux, and that app is windows/mac only.


> Post-processing using commercial tools may give better CMYK results.
> If you use external figures you may get better results converting them to CMYK
> before processing with xelatex as the conversion can be tweaked for each image.

Excuse my ignorance here, but is that a process that can be automated?
I'm guessing that if an image doesn't include a profile, then you're
stuck with checking it manually.

> 
> Many low-end tools do not convert RGB to CMYK reliably.  You may end up with
> "black" that has CMYK with small CMY values or map a range of colors to the
> same CMY values.  There are tools that help check color usage in a document --
> many printers use them and will refuse to print a file that has
> problems, but of
> course it is better if you can provide a high-quality PDF from the start.

Any of them that work on linux?

thanks

Clint