Hi,
Sorry for the delay. I've taken my time to think carefully about your question,
and ... well, response are below.
Regarding CSA, I'm touching the code. Seems it would be easier if lcms
generates only the dictionary without the %% comments and the
/Current exch /ColorSpace defineresource pop. The CRD is untouched.
Anybody has code that will be broken with that? PS generation is still a
new feature and hope changing this would have no bad effects.
> 1. Though I used "icc2ps -t1 ..." the CSA contains "/RenderingIntent
> (Perceptual)". Ist this correct?
Yes, as far as you used sRGB profile. Matrix-shaper profiles does only one
intent , and this is perceptual, because there is an implicit black point scaling.
If you were used a CLUT-Based with AtoB1 table, the intent would be
(RelativeColorimetric)
> 2. On the resulting print, the whole imageable area surrounding the
> printed objects - which should actually be white - comes out as a very
> light gray with a light blue cast (or should I say very very light
> blue?). Any ideas, what could be wrong?
This may be a bug. I'm currently trying to reproduce it.
> 3. BPC. Unfortunately the CRD generated by icc2ps does not perform BPC.
> I think I can't live without BPC any more for printing :-)
> Marti, may I put a "-b" option for icc2ps on my wishlist? I think the
> TransformPQR basically could perform a BPC, as the postscript
> interpreter also passes the src and dst black points to this function,
> doesn't it?
Ok, this is what has taken me time to think. Seems there is no easy way to
do so. Let's examine the facts. BPC is a compensation from source to
destination black points, and as such, only makes sense when creating
transforms.
Then, using CSA and CRD is same as delegating the transform creation to PS
interpreter, so, it should be the interpreter who applies BPC. We cannot
apply BPC to CRD since there is only a CRD for each page, but it can be
multiple CSA, one for each PS element. And nor to CSA, since there are may
be CSA already embedded in the document.
Any idea on how to do that?
Regards,
Marti
----- Original Message -----
From: "Gerhard Fuernkranz" <[EMAIL PROTECTED]>
To: "Lcms-User" <[EMAIL PROTECTED]>
Sent: Friday, August 08, 2003 9:03 AM
Subject: [Lcms-user] icc2ps, CRD and CSA
>
> Hi Marti,
> this is the first time I did some experiments with your icc2ps.
>
> Basically my goal is simple, I want to feed RGB postscript into
> ghostscript, gs should interpret this RGB as sRGB and the printer should
> print the "right" colors for the RGB values. In order to remap DeviceRGB
> to a CIE color space I
>
> * set "UseCIEColor" in the page device,
> * assigned an sRGB CSA to the DefaultRGB ColorSpace resource and
> * assigned a CRD generated from my printer profile with
> "setcolorrendering".
>
> So I prepended the following prefix to all postscript files which I
> wanted to print. The CSA and CRD are created with icc2ps, but I've done
> slight modifications manually -> setcolorrendering, setcolorspace,
> DefaultRGB:
>
> <<
> /ColorRenderingType 1
> /BlackPoint [0.0 0.0 0.0]
> /WhitePoint [0.964200 1.000000 0.824900]
> /MatrixPQR [0.40024 -0.2263 0.0 0.7076 1.16532 0.0 -0.08081 0.0457 0.91822 ]
> /RangePQR [-0.125 1.375 -0.125 1.375 -0.125 1.375 ]
> [...deleted...]
> /RenderingIntent (RelativeColorimetric)
> >> setcolorrendering
>
> << /UseCIEColor true >> setpagedevice
>
> [ /CIEBasedABC
> <<
> /DecodeABC [ { dup 0.0 lt { pop 0.0 } if dup 1.0 gt { pop 1.0 } if [0 5
> 10 15 2
> 0 25 30 35 40 45 50 55 59 64 69 74 79 84 89 94 99 104 109 114 119
> [...deleted...]
> /MatrixABC [ 0.436066 0.222488 0.013916 0.385147 0.716873 0.097076
> 0.143066 0.06
> 0608 0.714096 ]
> /RangeLMN [ 0.0 0.9642 0.0 1.0000 0.0 0.8249 ]
> /BlackPoint [0.0 0.0 0.0]
> /WhitePoint [0.964200 1.000000 0.824900]
> /RenderingIntent (Perceptual)
> >>
> ] /DefaultRGB exch /ColorSpace defineresource setcolorspace
>
>
> Baisically it appears to works fine. The colors of printed images look
> as expected, more or less the same as if I would convert sRGB -> printer
> CMYK with tifficc and then send CMYK postscript to gs. However, there
> are still some issues:
>
> 1. Though I used "icc2ps -t1 ..." the CSA contains "/RenderingIntent
> (Perceptual)". Ist this correct?
>
> 2. On the resulting print, the the whole imageable area surrounding the
> printed objects - which should actually be white - comes out as a very
> light gray with a light blue cast (or should I say very very light
> blue?). Any ideas, what could be wrong?
>
> 3. BPC. Unfortunately the CRD generated by icc2ps does not perform BPC.
> I think I can't live without BPC any more for printing :-)
> Marti, may I put a "-b" option for icc2ps on my wishlist? I think the
> TransformPQR basically could perform a BPC, as the postscript
> interpreter also passes the src and dst black points to this function,
> doesn't it?
>
> Thanks,
> Gerhard
>
>
>
>
> -------------------------------------------------------
> This SF.Net email sponsored by: Free pre-built ASP.NET sites including
> Data Reports, E-commerce, Portals, and Forums are available now.
> Download today and enter to win an XBOX or Visual Studio .NET.
> http://aspnet.click-url.com/go/psa00100003ave/direct;at.aspnet_072303_01/01
> _______________________________________________
> Lcms-user mailing list
> [EMAIL PROTECTED]
> https://lists.sourceforge.net/lists/listinfo/lcms-user
>
>
-------------------------------------------------------
This SF.Net email sponsored by: Free pre-built ASP.NET sites including
Data Reports, E-commerce, Portals, and Forums are available now.
Download today and enter to win an XBOX or Visual Studio .NET.
http://aspnet.click-url.com/go/psa00100003ave/direct;at.aspnet_072303_01/01
_______________________________________________
Lcms-user mailing list
[EMAIL PROTECTED]
https://lists.sourceforge.net/lists/listinfo/lcms-user
