[Openicc] PDF srgb Workflow

[Jan-Peter Homann]

Hello all,
In past discussions some people stated, that a colormanagement print 
pipeline can´t work with DeviceRGB PDF files and needs instead ICCbased RGB.

 From may point of view, the question depends on the possibilities of 
the pdftoraster engine. So far as I understand, poppler can´t transform 
DeviceRGB objects from sRGB to a printer profile.

But with GhostScript, this can easily eached by activating 
ICC-colormanagement for DeviceRGB objects and use the GhostScript 
default sRGB profile for this usecase.

As this GhostScript-option doesn´t has side effects for ICC-based 
content in PDF print spool files, we can start a color managed printing 
path with the print spool files produced by the vast majority aoff 
applications.

Concerning a poppler based workflow, I recommend to enhance poppler with 
this similar feature of GhostScript.
If g-c-m or Oyranos could either adress GhostScript or poppler in a 
similar way to provide the printer profile, we are mostly done.


As an addition, handling the rendering intent from sRGB to printer 
profile is much more easy, if its specified per printing session, than 
if it has to be hardcoded into every single ICCbased PDF objects, 
considering also that ICCbased PDF rendering intents can´t transport the 
information for blackpoint compensation.

best regards
Jan-Peter


-- 
----------  Please note the new adress --------------

homann colormanagement --------- fon +49 30 611 075 18
Jan-Peter Homann ------------ mobile +49 171 54 70 358
Cotheniusstr. 3 -------- http://www.colormanagement.de
10407 Berlin -------- mailto:homann at colormanagement.de