[Openicc] Linux printing

[Chris Murphy]

On Feb 28, 2012, at 12:06 PM, Michael Vrhel wrote:
> 
> 
> I guess we are talking about two different things here.  There are two "override" conditions.  
> 
> Case 1:  Suppose I have a source color space in a PDF file that is ICC based.  It is possible in Ghostscript to actually override that source color ICC profile and replace it with a different ICC profile.  To do this, requires the use of a command line option -dOverrideICC.   This is the type of command line option that one really would never use if they had a properly defined PDF file.  Apparently the customers for some RIP vendors receive all sorts of garbage PDFs and so they need to have the capability to override what the file says the colors are.  I agree that in a perfect world this would not be needed, but unfortunately I don't write all the PDF creation software.   User beware when they use this option and I doubt this command line option would be used by anyone but particular RIP vendors.

These are lazy people and lazy workflows and they should be punished. Seriously.

The chain of design to print workflows gives ample opportunity to deal with this situation. Content creation, PDF creation, PDF preflight @ customer, PDF preflight @ prepress/printer, PDF pre-press software usually as adjunct to the RIP itself, but does not actually occur "in-RIP". In each case the PDF itself is what's modified, not the RIP behavior.

To modify the RIP behavior means everyone else that came before the RIP means everyone else before the RIP has abandoned their responsibility, and competency.


In Case 2, I will need to further consider what you've written. I'm inclined to think that, again, if an actual ICC profile for OutputIntent is not in the PDF, that this is the job of upstream to explicitly define a profile.

And that's because an ICC output device profile is not just a color space or set of characterization data. It defines a transform. So if we're going to have correct PDF/X-3,4,5 proofing, the whole workflow needs to have already agreed on a specific OutputIntent ICC profile (or profiles once multiple OutputIntents per page are allowed, in PDF 2.0 I believe). Not merely a characterization set.


Chris Murphy