This function sets some basic text tags to make an ICC file better
formed.
The code is taken from LittleCMS, https://github.com/mm2/Little-CMS.git
git revision
lcms2.13.1-28-g6ae2e99 (6ae2e99a3535417ca5c95b602eb61fdd29d294d0)
file src/cmsvirt.c.
Suggested-by: Vitaly Prosyak <vitaly.prosyak@amd.com>
Signed-off-by: Pekka Paalanen <pekka.paalanen@collabora.com>
This adds a new test helper library that depends on LittleCMS 2.
For starters, the library implements conversion from enum transfer_fn to
ICC multiProcessingElements compatible LittleCMS curve object.
That conversion allows encoding transfer funtions in ICC files and
LittleCMS pipelines with full float32 precision instead of forcing a
conversion to a 1D LUT which for power-type curves is surprisingly
imprecise.
This also adds CI tests to make sure the conversion matches our
hand-coded transfer functions.
Signed-off-by: Pekka Paalanen <pekka.paalanen@collabora.com>
