/
2025-11-10 TSC Meeting notes

2025-11-10 TSC Meeting notes

 Date

Nov 10, 2025

 Participants

  • Carol Payne (TSC Chair)

  • Doug Walker (TSC Chief Architect) - Autodesk

  • Remi Achard (TSC) - DNEG

  • Sean Cooper (TSC) - Skydance Animation

  • Michael Dolan (TSC) - Epic

  • Zach Lewis (TSC)

  • Cuneyt Ozdas (TSC) - Autodesk

  • Mark Titchener (TSC) - Foundry

  • Kevin Wheatley (TSC) - Framestore

  • Cody Cueller - Adobe

  • Scott Dyer - AMPAS

Discussion topics

Removing Clamping in ICC Profiles: The team discussed removing clamping from ICC profiles in OCIO to better support HDR displays. Cody explained the current issues with clamping and its impact on color accuracy, particularly when using virtual displays. The group agreed that removing clamping would be beneficial, as it aligns with current practices and specifications. Doug mentioned the possibility of adding an HDR virtual display as a future feature, but this was not part of the current discussion.

ProPhoto Profile and OCIO Integration: The team also addressed a request to add ProPhoto color space support to the built-in ACES configs, with Vlad having made a pull request to include ProPhoto linear RIMM and a modified version with sRGB gamma curve. Doug expressed concerns about introducing an sRGB ProPhoto variant, fearing it could cause confusion. Cody and Doug discussed inconsistencies in the ProPhoto color profile, particularly regarding its gamma value and compatibility with Adobe applications. They agreed to follow up offline to determine the best approach for updating the profile definition.

OCIO in FFMPEG: The conversation then shifted to the potential integration of OCIO into FFmpeg, with Kevin expressing some reservations about how it would fit into the existing filter system. The team also discussed FFmpeg's LUT3D filter implementation and its interaction with Zscale. The group decided to continue the discussion about FFmpeg's implementation of OCIO in a separate thread.

Blender OCIO Environment Variable Concerns: The group discussed concerns about Blender's implementation of OCIO environment variables, where Blender has a separate Blender_OCIO environment variable that can override the standard OCIO variable. Zach explained that this could lead to troubleshooting issues when different applications behave differently based on environment settings, and suggested that Blender should either use the standard OCIO variable or implement a Blender_OCIO_disabled flag.

 Action items

  • Cody: Log an issue on the OCIO GitHub about removing clamping from ICC profiles for HDR support

  • Doug: Make a PR to remove clamping from ICC profiles and try to get it into the 2.5.1 release at the end of the year

  • Doug and Cody: Follow up offline to discuss ProPhoto profile implementation details regarding gamma curves and interop with Photoshop and Lightroom

  • Doug: Hold off on merging Vlad's ProPhoto pull request until comfortable it provides good interop

  • Carol: Reread the Blender OCIO environment variable PR discussion and potentially reach out