[XeTeX] Printers & PDFs created by XeTeX

[Jonathan Kew]

On 23 Jul 2007, at 2:01 pm, Evgenie Medvedev wrote:

> William Adams wrote:
>
>>   - RGB -> CMYK conversion
>
> 	I kept meaning to ask about that bit. My favorite printer company
> prefers PDF, but they also warn you that if anything inside is in RGB,
> fixing any color drift is your problem, since the best they can do  
> with
> it is print a proof.
> 	Is there a way to somehow ensure that all colors in a XeTeX-generated
> PDF are in CMYK already, through some special handling of images  
> before
> insertion or through a TeX mechanism? Failing that, is it possible to
> convert a resulting PDF to CMYK for printing somehow and see if  
> there's
> a problem before submitting?

If you're using xdvipdfmx as the output driver (via the -output- 
driver option on Mac OS X, or by default anywhere else), then I think  
you can specify colors as CMYK through the color package. (You can  
specify them as CMYK even if using the default xdv2pdf driver on Mac  
OS X, but it will convert them to RGB, so that doesn't help!)

For embedded images such as JPEG or PNG (or included PDFs), I assume  
the driver leaves the colors untouched, so if you ensure the images  
are saved as CMYK in the creating application, I'd expect them to  
stay that way.

(Most of this is guesswork, to some extent, as I'm not a color/PDF  
guru, and didn't write that code; it comes directly from the existing  
dvipdfm(x) driver.)

There might be PDF-inspection tools that could tell you what color  
space(s) your document is using... maybe William or someone else in  
that line of business can give suggestions?

JK