The LCMS 2.8 release candidate 1 has code for handling alpha channels
during ICC profile conversions:
"2.8 does support alpha channel transportation and a new transform
stride function and plug-in which can be used to increase significantly
the processing speed."
Perhaps this new code could be useful for helping GIMP make faster ICC
profile conversions? As there are a lot of profile conversions going on
with some of the new color management code, probably every little bit helps.
Here's the link to the announcement and discussion:
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