commit 1915b4d7ccd342e9194b0eaa7b065ace7a6dd823
author Christopher Cameron <ccameron@chromium.org> Tue Jun 03 20:43:38 2025 +0000
committer SkCQ <skcq-be@skia-corp.google.com.iam.gserviceaccount.com> Thu Jun 05 02:48:51 2025 -0700
tree 3e99115fade8be450f5c9263cf9cace351224ee9
parent e12ef7c0da42204e9276e0e183d903b1c03c2e53

skcms: Add PQ and HLG types

The PQ and HLG types differ from PQish and HLGish as follows:
- always use the constants from ITU-R BT.2100 (PQish and HLGish can
  use other constants)
- include an explicit parameter for scaling by HDR reference white
  (PQish and HLGish are capable of this, but the scaling is not an
  explicit parameter)
- for HLG, include parameters for the OOTF, namely, the peak luminance
  and system gamma (absent for HLGish)
- when used with SkColorSpace, will include the OOTF (absent for HLGish)

The skcms_TransferFunction_makePQ and skcms_TransferFunction_makeHLG
functions had no callers, to repurpose them to initialize these
types.

Once all use of PQish and HLGish is removed, we will be able to remove
PQish and HLGish entirely, so that we just have these PQ and HLG.

Bug: 420956739
Change-Id: If7a3fec007cd21825c3533272b865faf91fe5331
Reviewed-on: https://skia-review.googlesource.com/c/skcms/+/1002396
Reviewed-by: Christopher Cameron <ccameron@google.com>
Commit-Queue: Christopher Cameron <ccameron@google.com>
Reviewed-by: Kaylee Lubick <kjlubick@google.com>