I used black and white to keep it simple… for color the same issue you can see it was raised on github… I guess what needs clarification if what value is reported and is the way it is calculated correct, ie should it account for gamma or not… and how are the values handled when scaling, zooming previewing happens as there can be hue shift…
No sure the needle moved on this one… the impact of the correct module order for jpg was noted but still the calculations are not clear … at least to me…