I've been working on porting the Gimp lcms.c plug-in from using LittleCMS version 1 to using LittleCMS version 2. This will make possible high bit-depth ICC profile conversions. I'm not a super-experienced c-coder, nor have I ever worked with the lcms engine before. So I'm learning as I go. So far I've: (1)compiled the existing Gimp lcms plug-in, (2)modified the existing plug-in to use lcms2.h and attempted to compile it (knowing it would fail) (3)tracked down all the errors and warnings that result from the differences between LittleCMS version 1 and LittleCMS version 2 My next steps will be to add a whole bunch of "print to screen" commands to the current Gimp lcms.c plug-in so I can get a better handle on the flow of the code, and then start rewriting (or perhaps writing from scratch) the plug-in to use the LittleCMS v2 engine. If anyone is curious, I've documented what I've done so far: http://ninedegreesbelow.com/temp/gimp-lcms-1.html http://ninedegreesbelow.com/temp/gimp-lcms-2.html Comments, input is more than welcome. I have a couple of big-picture questions: Will Gimp be using as its internal working space some variant of Microsoft's scRGB? What about: Wikipedia: http://en.wikipedia.org/wiki/Scrgb "scRGB is a wide color gamut RGB (Red Green Blue) color space created by Microsoft and HP that uses the same color primaries and white/black points as the sRGB color space but allows coordinates below zero and greater than one. . . . the cost of maintaining compatibility with sRGB is that approximately 80% of the scRGB color space consists of imaginary colors." "Two encodings are defined for the individual primaries: a linear 16 bit per channel encoding and a nonlinear 12 bit per channel encoding. . . The 16 bit scRGB(16) encoding is the linear RGB channels converted by 8192 x + 4096. Compared to 8-bit sRGB this ranges from about 1/2 the color resolution near 0.0 to more than 10 times the color resolution near 1.0." That last sentence is a bit worrisome - losing resolution in the shadow areas. It seems to me that you will always need ICC profiles, to convert an image from whatever ICC color space profile it happens to be in, to your internal working space, and from your internal working space to the monitor profile, and from your internal working space back out to whatever color space profile the person wants to use to upon exporting to a non-xcf file. Yes? No? Elle -- http://ninedegreesbelow.com Articles and tutorials on open source digital imaging and photography _______________________________________________ gimp-developer-list mailing list gimp-developer-list@xxxxxxxxx https://mail.gnome.org/mailman/listinfo/gimp-developer-list
