[Openicc] Introduction / Gutenprint]

[Michael Sweet]

Robert L Krawitz wrote:
>    Date: Mon, 11 Apr 2005 21:01:18 -0400
>    From: Michael Sweet <mike at easysw.com>
>    Cc: openicc at freedesktop.org
> 
>    Gerhard Fuernkranz wrote:
>    > Michael Sweet schrieb:
>    > 
>    >> Basically you add cupsICCProfile attributes to your PPD file to
>    >> specify the output profiles for various printing modes supported
>    >> by your device. Normally the output profile selection is done
>    >> automatically using the current job options (media type, color
>    >> model, resolution, etc.), however it is also possible to include
>    >> the cupsICCProfile attribute in a print job to select a specific
>    >> profile, overriding the auto selection, e.g.:
>    >>
>    >>     lp -o cupsICCProfile=CMYK.Glossy.2880dpi filename.jpg 
>    > 
>    > 
>    > What does CUPS actually do with this parameter?
>    > Or in other words, who is eventually applying the profile, at which level?
>    > (and particularly, how is it done in the case "lp -o cupsICCProfile=... 
>    > filename.ps")
> 
>    The profile is applied by the RIP (any of the *toraster filters).
> 
> 1) So there's a hard-coded limit of three components to the name?
>    That seems a bit limiting...

Not in practice, and we have to deal with the 40 character limit for
option keywords in PPD files.

> 2) In CUPS 1.2, is there a 16-bit path from the RIP to the driver?

Yes, if the RIP supports it (also 32-bits per component, if supported)
FWIW, CUPS 1.1.x also supports 16/32-bits per component in the raster
format, however the imagetoraster and pstoraster filters do not yet
support it.

The imagetoraster filter in CUPS 1.2 will support 16-bits per
component.

The pstoraster filter in ESP Ghostscript 8.15.x (x > 1) will support
16-bits per component, however due to limitations in the Ghostscript
API only 15 bits of that will be significant, and on platforms that
do not support 64-bit integers the per component resolution will be
less, e.g. 11/11/10 for 3-components and 8/8/8/8 for for 4-components.

The cg*toraster filters in MacOS X 10.2 only support up to 8-bits per
component, but 10.3 and higher support 16-bits.

-- 
______________________________________________________________________
Michael Sweet, Easy Software Products           mike at easysw dot com
Internet Printing and Publishing Software        http://www.easysw.com