[Lcms-user] LCMS 2.16: CMMException: LCMS error 13: Mismatched alpha channels

[Philip R. <phi...@or...>]

JDK is using the flag cmsFLAGS_COPY_ALPHA. It is specified in a few 
cases including if
the source has alpha but the destination is opaque, expecting that the 
alpha channel will be ignored.

Here's where JDK started using the flag 
https://github.com/openjdk/jdk/commit/16acfafb#diff-eed6ddb15e9c5bdab9fc3b3930d5d959966165d9622ddd293e8572489adea98b

But in LCMS 2.16 there's a new check that this is running afoul of.
https://github.com/mm2/Little-CMS/commit/e55b6fa4d3c5b7e08d9e4bc8c803a79ca908b5a4#diff-3627f903d37617a227e71f0ee1[…]2629b5ee838707e3fcd7dcb46e762f4e

It seems to me that likely we could just drop specifying 
cmsFLAGS_COPY_ALPHA in this case,
but I can't find any background information on the reason for the change 
in LCMS, or awareness that
it might be a compatibility issue.

Thoughts / comments ?

-phil.