Attendance:

Guests:

• Omprakash Dhyade

Discussion:

• Documentation: 

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  • Nick: looks great 

  • Nick: There was a white paper that Florian wrote about color management. It has tutorial value.  Diagram with Yoda at the top.

  • Peter: “A Proposal for OpenEXR Color Management” http://openexr-23d3ef67-1ce7-aabf-1207-3cda2139e2e7.disney.io/www/OpenEXRColorManagement.pdf

  • Joseph: But it’s horribly outdated

  • Larry: What about OCIO docs? Noobie level.

  • Nick: But I’ve always wished for something concise.

  • Peter: It’s the other way around: OCIO says whatever you want to do, here’s how to do it. “Someone’s done some color management, now you need to understand it.”

  • Joseph: Some documents:

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    • https://www.arri.com/en/learn-help/learn-help-camera-system/image-science/aces/post-production

    • https://www.arri.com/en/learn-help/learn-help-camera-system/image-science/aces

    • https://www.arri.com/en/learn-help/learn-help-camera-system/image-science/color-faq

    • https://www.arri.com/en/learn-help/learn-help-camera-system/image-science/aces/aces-faq

  • Peter: We need a document that says, “If you need to know about color, go read this”

  • Joseph: it depends on the application, whether they use our chromaticities

  • Larry: But nobody gets the chromaticities right

  • Nick: “A well-formed file has these fields”

  • Peter: Nuke doesn’t write chromaticities unless you’re writing an ACES file

  • Joseph: If an exr file fell from the sky, the chromaticities say how to understand the data

  • Larry: A metadata story. Our renderer, before it writes out images, generates some stats and sticks it in as metadata. Stats were computed on the floating point data coming out of the render, but when the data got converted to half values, some small floating point values got converted to zeros as half but the metadata didn’t know that. “Aha, there are non-zero pixels here.” Was doing something for all black images.

  • Nick: I’d like to write a document, but don’t have time.

  • Peter: We need a guide for users of tools that work with exr images.

  • Joseph: What is the most notable thing about openexr? They’re linear. But they’re also scene referred.

• Darby

•  

  • ETA on the next release? Cary: should be soon, next week.

  • When fixing the memory mapped data issue, I discovered the API returns non-const  pointer, should be const.  Make a correction to the API?

  • For the test for the memory-mapped code, I wrote some useful classes, can I move them to the API? Cary: Yes, please.

• Larry: we have several things that we’ve been talking about but haven’t progressed on:

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  • ABI, Kimball

  • Core stuff underneath the C++ API

  • Threadsafe API

  • Convert python binding to PyBind