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suggestion for cmyk conversion

Posted: Mon Jun 06, 2005 4:50 pm
by juergen (guest)
i'm currently testing nconvert (linux) for on-demand web thumbnail creation. most image formats render very well (and fast), only CMYK colors are bad.

i know that implementation of ICC/CIE colors and ICC profile handling is far from being a trivial task (even if libraries like lcms, ICM, ColorSync et al do the math) but i'm wondering if it could be possible to implement some sort of simplified, generalized CMYK->RGB model to achieve 'similarity' to colorimetric ICC conversion.

for pdf/ps/eps: ghostscript (which nconvert engages to render ps/pdf) has the neat option

Code: Select all

-dUseCIEColors
that leads to a better CMYK->RGB conversion (based on ghostscript's standard CMYK and RGB color spaces). far from being accurate but IMO sufficient for thumbnails.
is there a way to pass this option to gs? (i've already tried to set -UseCIEColors als GS environment variable but no luck with nconversions)

thx

juergen

Re: suggestion for cmyk conversion

Posted: Tue Jun 21, 2005 3:06 pm
by xnview
juergen (guest) wrote:i'm currently testing nconvert (linux) for on-demand web thumbnail creation. most image formats render very well (and fast), only CMYK colors are bad.

i know that implementation of ICC/CIE colors and ICC profile handling is far from being a trivial task (even if libraries like lcms, ICM, ColorSync et al do the math) but i'm wondering if it could be possible to implement some sort of simplified, generalized CMYK->RGB model to achieve 'similarity' to colorimetric ICC conversion.

for pdf/ps/eps: ghostscript (which nconvert engages to render ps/pdf) has the neat option

Code: Select all

-dUseCIEColors
that leads to a better CMYK->RGB conversion (based on ghostscript's standard CMYK and RGB color spaces). far from being accurate but IMO sufficient for thumbnails.
is there a way to pass this option to gs? (i've already tried to set -UseCIEColors als GS environment variable but no luck with nconversions)
Ok, i'll add an option for that