Re: PQ HDR in PNG - draft review

For chrome to do  color management efficiently, everything needs to be done on the GPU.
Tables are generally much less efficient than doing using math on the GPU, and my impression
is that ICC v4 relies much more heavily on tables than ICC v2.

Yes, I see the point, but I don’t see there being more LUTs in V4 profiles than in V2, rather the opposite.
With v4 we can use the parametric curves instead of the sampled 1D LUTs in V2.
For example the standard sRGB profile  (colorimetric intent) can be created entirely without LUTs in V4, but requires LUTs in V2.
Ditto display profiles.

Lars