GSoC CM collaboration
ku.b at gmx.de
Sun Mar 2 12:16:15 PST 2008
Am 02.03.08, 21:01 +0100 schrieb Maarten Maathuis:
> On 3/2/08, Hal V. Engel <hvengel at astound.net> wrote:
> > Because it is a 3D problem. For output devices like monitors color management
> > maps from some absolute color space such as CIELab or CIEXYZ into the devices
> > color space in a way that corrects all colors not just those along the
> > neutral axis. The most you can do with the video card LUT is to get the per
> > channel gamma to be well behaved and the R=G=B axis to be close to neutral.
> > You can not get colors correct for R!=G!=B. This is a direct result of the
> > 1D limitation of the video card LUTs.
> > An example, where this becomes very apparent is with the newer LED based wide
> > gamut monitors. Even with a well calibrated video card LUT the display
> > colors where R!=G!=B, with out full color management, will be much too
> > saturated to the point of being garish. These monitors are starting to
> > become fairly common so this will only become more of an issue going forward.
> You're essentially assuming that the individual color channels are not
> linearly independent?
You cant correct a very saturated red from a wide gamut monitor with just
modifying the red curve to a less saturated red, say to match sRGB.
This colour transformation involves mixing in of some blue and green to
reduce the saturation. Hence it is no longer one dimensional.
You seems to be pretty interessted. Here some links and link collections:
developing for colour management
www.behrmann.name + www.oyranos.org
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