Academy Software Foundation Technical Advisory Council (TAC) Meeting - June 11, 2025

Join the meeting at https://zoom-lfx.platform.linuxfoundation.org/meeting/97880950229?password=81d2940e-c055-43b9-9b5a-6cd7d7090feb

Voting Representative Attendees

Premier Member Representatives

Project Representatives

Carol Payne - Diversity & Inclusion Working Group Representative, OpenColorIO Representative
Cary Phillips - OpenEXR Representative
Chris Kulla - Open Shading Language Representative
Diego Tavares Da Silva - OpenCue Representative
Jonathan Stone - MaterialX Representative
Ken Museth - OpenVDB Representative
Nick Porcino - Universal Scene Description Working Group Representative
Rachel Rose - Diversity & Inclusion Working Group Representative

Industry Representatives

Jean-Francois Panisset - Visual Effects Society

Non-Voting Attendees

Non-Voting Project and Working Group Representatives

LF Staff

David Morin - Academy Software Foundation
Emily Olin - Academy Software Foundation
John Mertic - The Linux Foundation
Michelle Roth - The Linux Foundation
Yarille Ortiz - The Linux Foundation

Other

James Spadafora, ILM
Ben Schofield, CDSA
Alyssa Alexis, SIGGRAPH
Cory Omand, Pixar
Karen Ruggles, DeSales University
Lee Kerley, Apple
Olga Avramenko, Sony Imageworks
Tommy Burnette, ILM
Doug Walker, OCIO / Autodesk
Bill Ballew, Dreamworks
Lorna DUmba, Framestore
Dhruv Govil, Apple

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Agenda

General Updates
- OpenQMC #434
- Open Source Days 2025 #1005
New Project/Working Group Proposal: RMTC (Rongotai Model Train Club) #1075
Annual Review: OpenFX #514

Notes

General Updates
- OpenQMC #434
- Open Source Days 2025 #1005
  - Emily: schedule on web site, lots of interesting submissions
  - Please finalize Virtual Town Hall proposals / schedule
  - Leadership meeting ahead of OpenSource Days
  - If anyone is doing anything else at SIGGRAPH involving our projects, please let me know so we can put it on our schedule
New Project/Working Group Proposal: RMTC (Rongotai Model Train Club) #1075
- No presenters
Annual Review: OpenFX #514
- No presenters
Larry OpenImageIO review was bumped up forward, but we have the slides, so we can do that
- Presentation Slides
- Daniel: will be requesting Graduation
- Mission
  - OpenImageIO is a toolset for reading, writing, and manipulating image files of any image file format relevant to VFX / animation via a format-agnostic API with a feature set, scalability …
- Major OIIO Components
  - Python bindings
  - oiiotool / maketx : ImageBufAlgo, ImageBuf
  - Renderers: TextureSystem, ImageCache
  - Common: ImageInput / ImageOutput
  - Format specific plugins: TIFF, OpenEXR, JPEG, DPX…
- Ecosystem role
  - Founded by Larry Gritz in 2008, joined ASWF in 2023
  - TSC: SPI, Weta, Blender, ARRI, Disney TV, Animal Logic, Autodesk, Laika
  - Dependency of OSL, OCIO, MAterialX, OpenUSD
  - Depends on: EXR, OCIO, VDB
  - Embedded in: Maya, Houdini, Katana, Blender, Arnold, 3Delight, Gaffer…
  - Used in approximately all studio pipelines
- ASWF year highlights
  - 396 git commits by 41 unique contributors
  - OIIO 3.0 release (Nov)
  - Release branch patches on the 1st of every month
  - We now distribute Python wheels for every release
  - Dev Days: 13 merged PRs in Fall 2024, 5 in Spring 2025
  - OpenSSF: passing 100%, Silver 95% (was 87%), Gold 78% (was 65%)
- OIIO 3.0: released fall 2024
  - Removed deprecated APIs, bumped many dependency mins
  - OCIO is now required - more consistent color mgmt
  - More robust building
  - Many key dependencies will now “auto-build” if missing
  - New formats: JPEG-XL, R3D
  - IBA de-mosaicing of raw images
  - New oiiotool commands: –cryptomatte-colors, –demoisaic…
- Commits since June 2024 - By contributor
  - Many returning and new contributors
  - Internally at Sony have drummed up a few interested contributors
  - Dev Days have been helpful, people have been joining. A bit less in 2025, but some nice contributions, hopefully some people will stick around.
- Roadmap 3.1 release this fall
  - Try to stay in sync with VFX Platform
  - Self-build of more dependencies
  - New formats: Ultra-HDR-in-JPEG, HTJ2K
  - Safer C++ APIs
    - TIRED: passing raw pointers + strides + implied/hoped-for lengths
    - WIRED: passing image_span that holds explicit bounds & strides
      - Requires more intentional declaration of memory layout by caller
      - callee can do bounds checking of accesses
  - More improvements to color workflow and nomenclature
    - Following work from Color Interop forum
    - Less guessing, more confirming to standard names, can assume we have OCIO features. Only in last main release did we make OCIO a hard dependency, before that some builds had it, some didn’t. And some builds might have had older OCIO. So could be large behavior changes, now can be more uniform.
  - Longer-term ABI stability
  - Hundreds of new small features & improvements
- Longer term roadmap / help-wanted areas
  - Ongoing part-time S-size tasks
    - Support, issue investigation, dependency wrangling, CI, security, releasing (ongoing)
    - Windows
      - Harder to deal with generally, senior devs are on Linux or macOS at work / home, so less familar with Windows.
  - Short term M-size work
    - Color management
    - Metadata strategy cleanup
      - Need “deep thinking”, some formats we support are long in the tooth, could use fresh eyes
    - Overhauls of: DSLR raw (especially metadata), HEIC, video/ffmpeg
      - Catching up on new capabilities of these dependencies
  - L-size work
    - CUDA / OptiX TextureSystem
      - TextureSystem used by high end renderers is currently CPU only, want feature parity with GPU implementation
    - Rust bindings
      - Different people have worked on but not completed, haven’t had a consistent enough push
- What’s working?
  - Used as extensively as ever, growing
  - Essential part of the VFX software ecosystem
    - Hard to find a DCC or studio pipeline that doesn’t use it
  - New features still being added / improved
  - TSC / meetings / extra eyes & hands
    - Formal TSC has been a boon to the project, never had regrets about joining ASWF
  - Lots of contributions (OIIO has > 230 contributors)
    - We may be under counting!
- Parting Thoughts
  - Mackerel!
    - If 5-6 big companies who use OIIO extensively…
      - Each had just 1 person dedicate consistent 20% time to OIIO…
      - Mostly doing things their own company needs (+ some maintenance)…
    - That would 2-3x the development velocity of OIIO
  - TAC: can we graduate?
    - Made a real effort on the best practices badge requirement, only missing items are the ones we agreed may not be so applicable / very hard to achieve. We are ready!
- TAC Open Discussion
  - Carol: this presentation ties into what we talked about TAC / TSC operation last meeting. Exciting to see the contributor list. Larry: when we joined ASWF, we saw we were having tail off from outside participation, now we see it has really picked up. Even recently some people are being involved with really thorny issues, wonderful to see.
  - Karen (chat): I liked to see the DevDays numbers too! Did you see people hanging around after their initial involvement? Larry: one person not previously associated came to us with an image viewer patch, since then has submitted 3-4 patches, has “caught the bug”, steady stream from that person. We had 13 PRs in the fall and 5 in the spring, not sure we have an explanation. Not sure if concerned with fall off, Dev Days team still looking at full accounting of results from last year, will make presentation at future TAC meeting.
  - Vote via email. JF: actually we just reached quorum (13 vs 12). We are still voting on renewal until we merge the changes. But this vote is mostly about graduation.
  - JF: propose motion to renew OIIO and move to graduated stage? Carol: seconded. But we lost quorum, so moving to LFX.
  - Carol: make sure to pay attention to LFX votes! Helps to not have to chase down people.
  - Michele: didn’t get enough folks responding to OpenCue, please take moment to respond to that. Working to set up on auto reminders, for now it’s manual (John or myself), so we can stay more on top of it.
Carol / Larry: we can use remaining time to discuss “how does the TAC / TSC works”, best practices, suggestions. We want to end of the hour and didn’t have time for discussion, so we can also have open discussion on that
- Presentation from 2 weeks ago
- Larry: one thing that wasn’t mentioned in the TAC, an important part is to have a good CI regime. The CI WG has done a good job of having ready made containers for the VFX Platform years, so for every project that is using CI, there’s a Docker container image with all the dependencies used by the project, the toolchain, so the threshold to getting CI up and running should be reasonably small. All projects need to take advantage of it. Having a robust CI that checks all the platform combinations on every PR is a key part of getting robust software that always builds.
- Larry: on my projects I’ve found it helpful to not just rely on these containers, but also run extra jobs that do other combinations. VFX Platform not always on cutting edge of toolchains, and other industries rely on our projects. So I test non VFX Platform combinations of compiler versions, C++ / Python versions, latest versions of components. I have a job that tests latest released version of all project dependencies. Also have a job that builds important dependencies at “top of their tries” and build our projects against, so we know as early as possible if a dependency is likely to break us in the future. We are all looking for ideas from other project.
- JF: there may also be value to using some common libraries: common XML / YAML parsing libraries for instance.
- Cary: it’s a multi-dimensional matrix. one dimension is compiler version, platforms. But another dimension is compilation options, CMake options, have had a number of regressions that have broken because of obscure build options we forgot about or weren’t paying attention to. Trying to augment the CI to be as diverse as possible to exercise libraries as thoroughly as possible. It’s a lot of work.
- Larry: it’s work to maintain, and also don’t want so many combinations that a PR has to wait 4 hours. Want to test everything, yet want quick feedback on PRs.
- Dhruv: testing against latest Clang would also be helpful. Apple stays close to latest, LLVM team aggressive in deprecating old things. Larry: if you haven’t looked lately at GitHub runners, they have different levels of Windows and Mac, and Linux and Windows on ARM (as well as macOS). Can get a decent diversity, shakes a lot of bugs loose to do multi platform builds.
- Lee: do other projects have strategies for long running CI? I’d like to add more, but… Any “Have your cake and eat it” strategies? Carol: what runs on a PR vs nightly / weekly builds, messing around with those cadences is something OCIO does. We don’t run latest stuff against every PR. You can change what folks see against their PRs. Still need to optimize, but try and keep developers happy.