[Openicc] Google Summer of Code 2009: Oyranos CUPS backend

[Chris Murphy]

On May 18, 2010, at 4:32 AM, Kai-Uwe Behrmann wrote:

> One further and related problem is a missed definition for marking prematched data.
> If someone creates a local proof and sends that ready for printing to a remote host, the colours are in danger to be double colour converted.

I will continue to advocate PDF/X-3 (X-4, X-5) as a model for this problem. Prematched objects should be marked with two pieces of metadata: that they are /DeviceRGB, /DeviceCMYK, /DeviceGray, /DeviceN as the case may be, *and* that there is an OutputIntent associated with the containing file (i.e. print spool file).

If this is deemed too complicated, then perhaps an explicit color management off flag for a print spool file should be considered. Apps prematching can specify this flag.

The PDF/X-3+ context though, allows for some smarter events to happen later on, for example a prematched document printed from a supporting application would only need to tag objects as /DeviceRGB, /DeviceCMYK, etc. and also specify an OutputIntent in the form of an ICC profile. That ICC profile in turn could contain a snapshot of the driver settings necessary to reproduce the intended printing condition. Instead of having to configure the app to color manage to a specific output condition, and then also configure the print driver dialog, the print driver dialog could be autoconfigured: resolution, media type, various other print modes, etc.

It's also possible at some point we have self-profiling devices. We already have printers that can identify the media that's in them. If that's fed upstream, it can cause our print spool file to be repurposed appropriately, even in the case of a prematched document *OR* alternatively warn the user after doing a print spool file OutputIntent vs. actual printer printing condition parity check, e.g. "Hey buddy, your print document is prepared for 'Plain Paper @ 300dpi" but "Glossy Photo Paper" is in the printer. Now what?"

Cancel
Repurpose Document (Color Manage)
Print As Is (Don't Color Manage)

It is kinda ridiculous the massive square dance under a full moon we have to go through to print things color management on Windows and Mac OS. I think there's a better and easier way for users, but I understand this stuff has to be coded by someone.


Chris Murphy