Notice of Meeting - ACES Gamut Mapping VWG - Meeting #27 - 9/3/2020

Discussions - ACESNext VWG – Gamut Compression/Mapping
1

ACES Gamut Mapping VWG Meeting #27

Thursday, September 3, 2020
5:00pm - 6:00pm Pacific Time (UTC-12:00am Friday)

Please join us for the next meeting of this virtual working group (VWG). Future meeting dates for this month include:

  • 9/10/20, 9:30am
  • 9/17/20, 5pm
  • 9/24/20, 9:30am

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United Kingdom: +44 330 221 0097Meeting #25 - 8/20/2020

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Hi,

The stripped out/barebone model can be picked up here: https://github.com/colour-science/aces-vwg-gamut-mapping-2020/releases/tag/barebone-model

Cheers,

Thomas

3

Recap:

  • Where did the 1.2 power value come from in the original default?
    • @nick : we could look at the half-float quantization for the upper limit to make sure invertibility is functional
  • @Thomas_Mansencal: we should put that nuke script and collab for the default values in the repo for tracking
  • @matthias.scharfenber will calculate the effective primaries of a few DSLRs from the DNG matrices to see if they would make any difference to the limits
  • @sdyer checked with @Alexander_Forsythe about the zero-clamp in the ACES to ACEScg CTL - Alex doesn’t have too much more information on the history - we all agree it should be gone. Scott is going to push a hotfix now, and talk with Alex about official release (along with the gamut mapping work?)
  • @sdyer noted that the CC24 RGB values in the spreadsheet Nick used are the ones up for inclusion in the revision of SMPTE 2065-1-004.
  • The group seemed fine with the default choice of 3 decimal places of precision on threshold and distance limits

Recording and Transcript