Hi Richard,

> I'm trying to create a v4 D65 profile using
> cmsCreateProfilePlaceholder() and settings values myself.

Fine.

> If I understand correctly, all v4 profiles have to have a D50 whitepoint
> and a 'chad' adaption tag to convert to and from the real whitepoint.

Well, this only applies on *display* profiles. On all other cases
you need to store the media chromaticity adapted to D50. The CHAD is used
to store the illuminant. So, if you create a profile for a printer using
bond paper, and you use a F11 as light source, you need a CHAD from F11 to
D50 and then the white of bond paper adapted as seen under D50

> The only way to write the chad seems to be from cmsCreateRGBProfile()
> so creating a v4 D65 profile looks basically impossible using
> cmsCreateProfilePlaceholder().

Why? You can just do something like:

    cmsMAT3 Matrix = {...};
    cmsWriteTag(hProfile, cmsSigChromaticAdaptationTag, (void*) &Matrix);

This works fine on profiles allocated by cmsCreateProfilePlaceholder
But of course, the calculation of the matrix is then up to you...

Otherwise I still don't understand where the issue is :-?

Regards
Marti


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