[Openicc] Print Color Pipeline

[Jan-Peter Homann]

Hello Richard,
Did I understand correct:
It is technically possible, that the printer driver tells colord, which 
profile is valid for a setting, and  the user has not to configure , the 
profile  in colord?

I read

http://gitorious.org/colord/master/blobs/master/src/org.freedesktop.ColorManager.Device.xml

as I´m not a developer, I hade the impression, that this XML-file 
describes mostly different driving settings in a standardized format and 
also which ICC-profile is actually assigned to the device / setting.

 From my point of view, the part of assigning an ICC-profile to a 
printer driver setting could be handled internally in the printer driver 
and may don´t needs an external database with detailed driver settings

Lets assume, the printer driver will be delivered with canned profiled 
and the user is forced to create (named/serialized settings/queues) like 
e.g.

1) plainpaper-draft
2) plainpaper-high-quality
3) mattpaper-high-quality
4) Photopaper-best-quality

Is it correct, that now the printer driver should create for every queue 
a "Gnome ColorManager Device ID" and deliver the canned ICC-profile for 
this setting / queue also to colord, where it is imported in mapping.db 
and storage.db

If now the user push the print button for a predefined setting, The 
Gnome Color Manager gets a signal with the DeviceID and delivers the 
correct Device Profile to the appplication / service which renders the 
print data to color managed bytemap for the printer driver.

At printer driver level, there is no colorconversion involved (only 
screening and applying internal 1D LUT calibration curves, ink limites 
per channel and so (predefined from driver vendor for this setting)
Colormanagement of application data for monnitor or print out would be 
pretty similar from the standpoint of the application which sends data 
to the monitor or to the printout.

Now, the user  wants for his preferred photopaper his own profile.
In the driver, he changes the queue settings for 
"Photopaper-best-quality" by activating the Option "Testchart-Printing". 
By activating this option the driver sends "ProfilingInhibit" to colord.
If the testchart will be printed, the Gnome Color Manager tells the 
application / service which renders the data for printout not to apply 
any color conversion.

The user measures the testchart or sends it to a profiling service and 
gets an ICC-profile for "Photopaper-best-quality" back. Now the user 
activates the driver Option "Install new profile" for the setting / 
queue. If the user is doing this, he imports the profile and the driver 
sends to colord an information that the profile in the mapping.db has to 
be updated for this setting / queue.

Optional, during the installing process of the ICC-profile, a additional 
tag will be added to the ICC-profile describing the driver setting.

*****
- Could the described workflows be realized with colord ?
- Are there any applications, which already make use of the Gnome Color 
Management for rendering both to the monitor and the printout ?
*****

Best regards
Jan-Peter












Am 24.01.11 11:49, wrote Richard Hughes:
>> If the printer profile should be configured in the driver, we need a
>> mechanism, that the driver can tell the system, what is the current valid
>> profile for the choosen driver setting.
> Sure, have a look at the colord DBus introspection files, e.g.
> http://gitorious.org/colord/master/blobs/master/src/org.freedesktop.ColorManager.Device.xml
>
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