Re: [Openicc] colord 0.1.0 released!

[Leonard Rosenthol <leonardr pdfsages com>]

On Mon, Jan 17, 2011 at 9:56 AM, Robert Krawitz <rlk alum mit edu> wrote:

To be even more precise, what we really mean is to turn off all color

management at the system software level.

Yup!

 

The real issue here is making sure that CUPS and its filter chain

don't modify color data on the way down unless they're told to, and
when they do so, it must be predictable.  

In this case, we're talking strictly about raster-based printers, correct?  Postscript, PCL, etc. based devices aren't part of this mix, since color management is handled in a completely different manner for such devices - yes?

 

That's the problem on OS X:
there doesn't seem to be any way to ensure that data from the
application reaches the printer (or driver) unmodified.  In other
words, if we send an RGB tuple (97, 38, 108) from an application, we
have no way to guarantee that Gutenprint sees that same RGB value.

There are solutions for this for certain printer models, where the device vendor has provided their own private APIs to enable applications to bypass the OS.  Photoshop, for example, does this when it can (on both Mac OS X and Windows).   NOTE: I am still trying to get this info published, but it's not under our control and for reasons I have yet to fathom, they don't see the need for other apps to play too :(.

Leonard