weston/tests/lcms_util.h
Pekka Paalanen 44c3079567 tests: add lcms-util with MPE curves
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>
2022-06-03 10:22:25 +00:00

37 lines
1.3 KiB
C

/*
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#pragma once
#include <lcms2.h>
#include "color_util.h"
cmsToneCurve *
build_MPE_curve(cmsContext ctx, enum transfer_fn fn);
cmsStage *
build_MPE_curve_stage(cmsContext context_id, enum transfer_fn fn);