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| '''Potential mentor''': Carnë Draug | | '''Potential mentor''': Carnë Draug |
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| === Color management functions in image package ===
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| {{Warning|requires review and mentor}}
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| The goal is to implement these functions:
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| iccread
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| iccwrite
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| makecform
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| applycform
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| These functions are useful for color management, in particular for converting data (especially images) between color spaces. ICC profiles are essentially used to store look-up tables or matrix transforms (or both) that define the conversions. For example, to convert an CMYK image to sRGB, you would load a "print" ICC profile that defines the conversion from CMYK to L*a*b* (the CIE color space that is supposed to match the human visual system), then load another profile that defines the conversion from L*a*b* to sRGB (there is a standard profile for this conversion (IEC 61966-2-1), which is why Matlab has a built-in conversion from sRGB to L*a*b*). To do the above conversions in Matlab, you would use the following code:
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| <syntaxhighlight lang="octave">
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| cmykImage = double(imread('cmyk-image-filename.tif'));
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| iccProfile = iccread('icc-profile-filename.icc');
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| labImage = applycform(cmykImage, makecform('clut', iccProfile, 'AToB3'));
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| rgbImage = applycform(labImage, makecform('lab2srgb'));
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| </syntaxhighlight>
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| The <code>'AToB3'</code> selects one of the color transforms (look-up tables) contained in the profile. This one is "Absolute Colorimetric." More details on ICC profiles may be obtained from [http://www.color.org/icc_specs2.xalter the ICC spec].
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| Knowledge of ICC profiles (at least knowledge of their application) would be a prerequisite. Since [http://www.littlecms.com/ littlecms] implements all the necessary functions for reading, writing, and applying profiles, it would be primarily a matter of integrating this library into Octave (assuming that is the preferred implementation -- one could certainly read the ICC files directly, but why reinvent that particular wheel).
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| '''Required skills''': C++ programming, some knowledge of ICC profiles desirable.
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| '''Difficulty''': Easy.
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| '''Possible Mentor''': TBD
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