婆罗门
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战斗力 鹅
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注册时间 2011-4-2
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还有这段
Generally you can differentiate between two types of profiles: LUT based and matrix based.
Matrix based profiles are smaller in filesize, somewhat less accurate (though in most cases smoother) compared to LUT based types, and usually have the best compatibility across CMMs, applications and systems — but only support the colorimetric intent for color transforms. For matrix based profiles, the PCS is always XYZ. You can choose between using individual curves for each channel (red, green and blue), a single curve for all channels, individual gamma values for each channel or a single gamma for all channels. Curves are more accurate than gamma values. A single curve or gamma can be used if individual curves or gamma values degrade the gray balance of an otherwise good calibration.
LUT based profiles are larger in filesize, more accurate (but may sacrifice smoothness), in some cases less compatible (applications might not be able to use or show bugs/quirks with LUT type profiles, or c**ain variations of them). When choosing a LUT based profile type, advanced gamut mapping options become available which you can use to create perceptual and/or saturation tables inside the profile in addition to the default colorimetric tables which are always created.
L*a*b* or XYZ can be used as PCS, with XYZ being recommended especially for wide-gamut displays bacause their primaries might exceed the ICC L*a*b* encoding range (Note: Under Windows, XYZ LUT types are only available in dispcalGUI if using Argyll CMS >= 1.1.0 because of a requirement for matrix tags in the profile, which are not created by prior Argyll CMS versions).
As it is hard to verify if the LUT of an combined XYZ LUT + matrix profile is actually used, you may choose to create a profile with a swapped matrix (which I'd recommend), ie. blue-red-green instead of red-green-blue, so it will be obvious if an application uses the (deliberately wrong) matrix instead of the (correct) LUT because the colors will look very wrong (e.g. everything that should be red will be blue, green will be red, blue will be green, yellow will be purple etc).
Note: LUT-based profiles (which contain three-dimensional LUTs) might be confused with video card LUT (calibration) curves (one-dimensional LUTs), but they're two different things. Both LUT-based and matrix-based profiles may include calibration curves which can be loaded into a video card's gamma table hardware.
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楼主: boday
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发表于 2015-2-4 14:37
