Palette aco has cmyk colors. Suspected problem: Krita directly loads the cmyk values in the aco file into a cmyk color, but assumes it is srgb therefore it gives the incorrect color. Test case A works correctly: 1. Create a cmyk document 2. Draw a color from aco palette http://lts.cr/sd/5SS4 3. Export the document to psd 4. Load document in photoshop 5. Draw a color from the aco palette 6. Compare with color in document 7. Color is the same Note: I tried to export tiffs or pdfs and comparing, but the colors were incorrect. So I'm using photoshop... Reproducible: Always Steps to Reproduce: 1. Create a rgb document 2. Draw a color from aco palette http://lts.cr/sd/5SS4 3. Export the document to psd 4. Load document in photoshop 5. Draw using the palette in photoshop. 6. Compare with color in document Actual Results: The two patches have different colours. Expected Results: The two patches should have the same colour. On Windows 8.1
Created attachment 88824 [details] Copic_358_ColorChart
Created attachment 88825 [details] Slightly different palettes
You expect the palette to give the exact color when you use it, but in another color space. Note: this does not work when you convert color spaces for the entire document.
Hm, we do load the cmyk aco palettes as cmyk colors in KoColorSet.cpp, 491-498: else if (colorSpace == 2) { // CMYK e.color = KoColor(KoColorSpaceRegistry::instance()->colorSpace(CMYKAColorModelID.id(), Integer16BitsColorDepthID.id(), "")); reinterpret_cast<quint16*>(e.color.data())[0] = quint16_MAX - ch1; reinterpret_cast<quint16*>(e.color.data())[1] = quint16_MAX - ch2; reinterpret_cast<quint16*>(e.color.data())[2] = quint16_MAX - ch3; reinterpret_cast<quint16*>(e.color.data())[3] = quint16_MAX - ch4; e.color.setOpacity(OPACITY_OPAQUE_U8); } What can happen, I guess, is that Photoshop uses a different way to convert the cmyk color to rgb. I'm not yet sure what I can do here.
I'm guessing, but it's undocumented, that photoshop doesn't color manage the colors in its palettes.
Palette files are now color managed, but ACO files aren't. So, without knowing what CMYK profile was intended for an ACO file, there will still be issues with color reproduction.