HDR reference white in ICC profile.

Wolthera van Hövellrequested to merge
woltherav/krita:handle-hdr-reference-white-for-perceptual-quantizer-curves into master

Implement retrieving the perceptual quantizer reference white from the profile. This way, we can finally support different nits values for the perceptual quantizer curve, which is necessary if we want to shift to 203 nits by default.

Part of #86 and part of #95

Todo:

  • We need to decide which profile is the default in the registry.
  • Searching for nits value needs to be implemented in profileFor
  • The small color selector needs to have its definition of HDR widened.
  • Test need to be modified so they at the least get the 80nits profile by default.

Test Plan

Load the 180 pq profile, or convert a linear profile image to rec2100 pq (203cd/m²).

Formalities Checklist

  • I confirmed this builds.
  • I confirmed Krita ran and the relevant functions work.
  • I tested the relevant unit tests and can confirm they are not broken. (If not possible, don't hesitate to ask for help!)
    • TestIccFromColorimetry
    • kis_png_test
    • kis_kra_loader_test
    • TestLcmsRGBP2020PQColorSpace
    • New reference white tests in TestProfileGeneration
    • kis_tiff_test
    • conversion between PQ 80 and PQ 203 roundtrip.
  • I made sure my commits build individually and have good descriptions as per KDE guidelines.
  • I made sure my code conforms to the standards set in the HACKING file.
  • I can confirm the code is licensed and attributed appropriately, and that unattributed code is mine, as per KDE Licensing Policy.
  • Does the patch add a user-visible feature? If yes, is there a documentation MR ready for it at Krita Documentation Repository?
Edited by Wolthera van Hövell

Merge request reports