Academy Software Foundation - Technical Advisory Council (TAC) Meeting - November 1st, 2023

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

Voting member attendance

Premier member Representatives

Project Representatives

Carol Payne - OpenColorIO Representative
Cary Phillips - OpenEXR Representative
Chris Kulla - Open Shading Language (OSL) Representative
Jonathan Stone - MaterialX Representative
Joshua Minor - OpenTimelineIO Representative
Ken Museth - OpenVDB Representative

Industry Representatives

Jean-Francois Panisset - Visual Effects Society

Non Voting Projects, Working Groups, Linux Foundation

Other Attendees

Doug Walker, OCIO / Autodesk
Olga Avramenko, MPC
JT Nelson, Pasadena Open Source consortium / SoCal Blender group
Sean McDuffee, Intel Corporation
Bill Ballew, Dreamworks
Joseph Goldstone, ARRI
Daniel Hekcenberg, Netflix

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Agenda

Annual Review - rawtoaces #475
Annual Review - OpenColorIO #474
Project Proposal - OpenQMC #434

Notes

Annual Review - OpenColorIO - Carol Payne / Doug Walker - ASWF TAC Update - November 2023
- OpenColorIO ASWF TAC Review 2023 Slides
- Can extend if we have more time than 30 minutes today
- Feel free to chime in on the slides if you have comments, don’t feel the need to wait until the end since we’ll be jumping around quite a bit
- May diverge a bit from standard format
- Technical Steering Committee
  - 2 new members this year: Thomas Mansecal (WetaFX) and Zack
- Project Longevity
  - Real talk: OCIO looks great from the outside, but we have the same issues as all ASWF / Open Source Projects
    - Without the continued sponsorship of Autodesk, the project would likely go back to reading water
    - Struggle with consistent, dependable involvement (i.e. code reviews)
    - TSC is made up of many experts, but most aren’t contributing code on a regular basis
    - Get a decent amount of one-off contributions, but struggle to retain into regular committers
  - Contributors
    - LFX Insights dashboard data seems hard to interpret, for instance it mentions 161 contributors which isn’t the case. Can get more info from other graphs, such as commits from new contributors, seems within reason of what we’ve done on the project and number of new contributors.
      - Ken (chat): The number of commits is a misleading metric of the amount or quality of contributions to a project
      - We did have 6-7 contributors with Dev Days.
      - Interested to see if anyone has had similar experience with LFX Insights, is it because our project is too small and it’s designed for larger projects?
- SMPTE Workflow Systems Medal
  - Accepted by Carol and Doug
  - Hope to see more open source projects getting this kind of recognition from standards bodies, first time an open source project had won a SMPTE award
  - David: the address that Carol and Doug did about each other, the foundation, the project, was very generous, well articulated, they were great representatives for all of us and what is happening at ASWF, support for the project from Autodesk. It was well done and heart warming.
- The past year
  - V2 Config Release
  - V2.2.0 Completed CY 2023 VFX platform release
  - V2.2.1 ABI compatible features and fixes
  - January 2023 V2.1.3, V2.0.5: ABI compatible backports
  - August 15, 2023: Config update v2.0.0 pre-release
  - August 31, 2023: v2.3.0 CY 2024 VFX Platform release
- v2.3.x delivered new feature highlights
  - …
- v2.3 - Config Merging Tech Preview
  - Releasing this fall as a “tech preview” alongside 2.3
    - Will be available in a separate branch
    - Gives more time for community review & discussions
    - Common use-cases
      - Enable configs to be built up from components
      - Allow applications to transparently add required color spaces
      - Make it simpler to add a LUT to an existing config
  - A big workflow change, how does it work when building a VFX pipeline, or a DCC using OCIO. Has lots of potential benefits, but opens up lots of questions for which we don’t have all the answers. As a TSC, could not come to a full consensus on adding this feature as a part of 2.3, so we decided to release it as a tech preview so people can try it out, get feedback, and hopefully answer open ended questions before releasing at next release (2.4)
  - Wanted to highlight to the TAC as a use case of the TSC, this went down to a vote for people for and against inclusion and we didn’t get consensus, this is what we are trying as a solution. We think there’s value to this approach, but not sure. Looking for feedback from the TAC, see if anyone has opinions on this approach, or share approaches used in other projects: a feature that’s somewhat controversial. This was an interesting challenge to deal with.
- What’s next (Doug)
  - Open Source Roadmaps
    - Open source Projects present planning challenges
      - Velocity is highly unpredictable
        
        Volunteers & expertise come and go
      - Apps that have integrated OCIO may have difficulty planning
        
        What will be the new features & when will they arrive?
    - Goal: Develop a roadmap for the fall 2024 release
      - Give better visibility into the features under consideration
      - Identify features that are underway and likely to make the release
      - Try something new for that release, looking for any wisdom to be shared from other projects. Please reach out to Carol / Doug.
  - Future Plans (tentative plans, under consideration)
    - Trends of note:
      - Increasing importance of web & mobile platforms
        
        Having a lighter weight version of the library would help
        
        Having JavaScripts bindings would help
      - Demand for pure shader-based transforms without LUTs
        
        Allocating LUT textures is more costly on lower-end hardware
        
        OCIO is now able to do more without needing LUTs
        
        Can we provide a transform layer that would be easier for implementors to deal with, not having to allocate LUT textures on GPU
    - OCIO for web
      - Smaller version of library with fewer dependencies
      - Primarily aimed at GPU processing (shader output)
      - OCIO.js binding
      - Some restrictions compared to the full library
        
        eg probably no FileTransform / LUT support
      - Gordon: is that WebAssembly / cross compiled? Doug: TBD, we haven’t really investigated technical solutions yes. Carol: we have talked about this at SIGGRAPH, talked about Javascript binding, WebAssembly, but no real exploration yet. Gordon: many people are trying to get USD / Hydra as WebAssembly, we depend on OCIO, Hydra stuck between OCIO v1/v2, would be great to get this into WebAssembly, if I can help connect to people working on Hydra, that would be great. Doug: have been talking with people on the Autodesk side, one of the use cases we had in mind. Will follow up with you.
      - Nick Porcino (chat): Pixar is working on the architecture for color management in USD now. Happy to connect on the topic. - JC Morin: If you want a good example of how to write a JS binding, MaterialX’s JS bindings are a great resource.
    - ACES v2 - top priority, should release early next year
    - Better integratons with OS-level display color management
    - Grading workflows / shot-based looks
    - Common LUT Format (CLF) v4
    - Vulkan support
    - Improved OpenEXR interop
    - Default Viewing Pipeline enhancements
    - Improved ACES Metadata File (AMF) support
    - Config diff tools
- Working Group Updates
  - 2 Active working groups: OCIO Config WG and OCIO UX / UI WG
  - OCIO Configs Working Group
    - Started 2-3 years ago
    - Goal: provide a curated set of color space implementations
      - Targetting VFX, animation and games industry
      - Currently providing several configs (now built-in to the library itself):
        
        OCIO CG Config for ACES (light-weight, minimal collection for CG)
        
        OCIO Studio Config for ACES (full ACES, for compositing & post production)
      - These configs provide ACES as well as other commonly used spaces
        
        The non-ACES spaces are for texturing, linear camera spaces, etc
    - Config Methodology
      - Naming / Version Control
        
        studio-config-v2.0.0_aces-v1.3_ocio-v2.3.ocio
        
        v2.0.0 : config version
        
        v1.3 : ACES version
        
        v2.3 : OCIO library version
      - ACES-based, but not bound
        
        Some exclusions:
        
        Certain Output Transforms (ex: DCDM)
        
        Superseded Input Transforms (ex: SLog1, REDLogFilm)
        
        ACESproxy
        
        Old ACES Emulations
        
        Some additions:
        
        sRGB texture spaces
        
        Utility linear spaces
- OCIO Color Interop Forum
  - Goal: encourage color space interop across industry projects
    - The Configs WG already includes a variety of stakeholders
      - ACES, camera vendors, exports from VFX, animation, games, post
    - But would like broader participation
      - Other ASWF projects, OpenUSD, more app developers
    - Aiming to coordinate discussions around color space support
      - What is the list of color spaces, how should they be named, etc
    - Looking for advice about how to get more people involved
      - Particularly those not currently using OCIO
      - Validate some of what Doug / Carol / Thomas Mansecal / Kevin Wheatley have been working on
      - Would be different to how we are currently running a WG
    - Do we need another completely separate config for a different workflow
    - Would like to get feedback from TAC, want agenda items brought to us, rather than us setting the agenda. Bring OCIO ACES v2 config questions…
    - Doug: this is possibly broader than OCIO: color management support in various applications and workflows, we would like them to use OCIO, but even if they don’t, people want to create workflows. So we need interop between projects and applications, and thus broaden the scope of the group to even people who aren’t using the OCIO configs.
- Gordon: is the ask from the TAC “here’s what we need, process, blessing”, what would you like to get from the TAC? You’ve done amazing things with the project, in general, what are your asks of ASWF. Carol: we’re asking for ‘blessing’, this is something we are taking up as leader of the effort, we can get into details of where this is hosted, what calendar is it on, does it make sense, does it address color issues in your projects? Doug: there’s been discussion about other ASWF projects that are interested in color management adopting OCIO / improving their color management. Interop between ASWF projects is an interesting subject for the TAC to discuss, how that should best be done. There are probably other areas outside color where we could improve interop between projects. Also how to publicize that, that the ASWF is setting up a cross project interop WG, and want to invite stakeholders to participate. Gordon: in the spirit of not taking ages to make decision, OCIO is the flagship color spokesperson in ASWF. I would like to move a motion that the TAC supports you and blesses this approach. Can we do this without Kimball? David: please go ahead, we can do this as a motion of support, before we do that, a few notes from experience. We have a lot of projects in the foundation, at beginning of OCIO presentation, presented that it can be hard to get new contributors. So if we add a new project (which is totally valid), perhaps it would be good to further define its mission, and perhaps define a first, short time deliverable. If the color interop forum is to deliver something in first 6 months, it would help focus the minds of people, help people joining not to feel they are joining a long running, ongoing project. Could provide a milestone from the start? Gordon: wasn’t thinking of it as a project, more a forum that OCIO can use to engage with a broader set of stakeholders. How should we characterize it? Is it an independent project, or a forum that OCIO uses? Carol: the latter, don’t want to downplay the amount of work. For me it’s the continuation of the Configs WG, broadening its scope. So more work, but we feel it’s the natural continuation of work. The Configs are stabilizing, they will need to keep being developed, but not as much huge develop effort. We need more to know if they are being used, what the next steps should be. So information and feedback gathering, making that work cross project, which will turn into more development work. Gordon: encouraged that you would take it on, want to encourage going forward. Yarille: do we have quorum? JF: 11 present, 15 not present, so we do not. Yarille: we can do this as a email vote. Gordon: maybe we need more info we want to see first before email vote goes out? Carol: happy to put things in writing. Yarille: yes, can attach to email. Gordon: it seems like it’s an iterative process. Yarille: will include presentation and minutes in email. Carol: will provide statement afterwards.
- Eric R: creating an ASWF ecosystem, how do the projects interact. This comes up in OTIO, it’s natural that people see how OTIO can carry around information, want to lean on domain expertise in other projects. A separate thing we might consider instead of a regular cadence WG, could have a once or twice a year ASWF Interop Summit. Carol: more and more crossover between projects, so would support that. The TAC is a good place, but our agendas are full. David: do we hold this interop forum at our conferences / open source forum in Feb / Open Source Days at SIGGRAPH? Eric: yes, would be good to hold in those contexts, but could eat up 1/2 or full day, so not sure. Maybe try something smaller first. David: great idea, evolve our events to include forums like this.
- Jonathan: want to support OCIO color interop. In my mind could be an expansion of the scope of what OCIO could be in the future, could be more than just a code base, but a standardization of color spaces. Does that sound like what you are thinking about? Would align with conversations happening in USD / MaterialX spaces, an expansion of what OCIO could be in the future. Doug: OCIO has had close collaboration with ACES project, we’ve relied on ACES to define color spaces, with OCIO being a way to implementing them. Something we should have some discussions in collaboration with ACES leadership to make sure we are aligned on purpose. Specific goal right now is interop between colorspaces that already exist, and practical aspects of how do you communicate color space information between different applications. We want to be careful how we describe scope and objectives to take that into account. Jonathan (Chat): The USD color architecture will likely be common to USD and MaterialX, so we’d love to join this conversation. This may be a great place to talk about how people should think about OCIO and AMF in the same world
- Eric: in the work we’ve been doing at Netflix, would love a library of mutually agreed upon color transforms to get between spaces. Take the discussion out of that, instead of having to reinvent it all the time. Carol: we would like to dig into examples, we do have for colorspaces that have open definitions, a large set of transforms which should be representative. We’ve talked about how we can add to that, it’s not a standard, it’s our implementation of the standard.
- Gary (Chat): OpenFX is also very interested in this kind of color interop. It’s an active discussion topic for us.
- Doug: as to AMF, this is something we’re working on actively in OCIO to go beyond last year’s prototype.
- Carol: question from Gordon as to what’s most important to use. We incredibly benefit from all the work being put into CI working group, whatever we can do to continue to fund this, GPU runners are essential. We have people who participate in that group, but we aren’t necessarily experts. That’s huge for us, probably biggest point on the list to “give more resources”. That would be our #1 ask. Also small requests around LFX Insights, small notes and nudges, would need some help on how to better use this. LF putting lots of effort into it.
- Doug: completely agree, work of CI working group has been super helpful, we also leverage Emily’s work for marketing.
- Carol: continuing initiatives to bring new developers is important, build on Dev Days, other learning initiatives. Having events specific to the foundation that are catered to our unique industry is important, make the events repeatable. Bring in contributors interested in this industry, rather than wider efforts.
- Gordon: great to hear about importance of CI WG, would be great to get a debrief on how we think Dev Days went.
- David: thank you for all the great work OCIO, and the idea of the crossover forum.