**Session Date/Time:** 28 Jan 2025 20:00

# [CELLAR](../wg/cellar.html)

## Summary

The CELLAR Working Group discussed the status of several in-progress drafts (`tags-15`, `codec-14`, `chapter-codecs-5`, `control-5`), potential errata for the published `RFC 9559`, and ongoing developments for FFV1 Version 4. Robert Sparks was welcomed as a new co-chair. Key discussions included proceeding with `tags-15` to Working Group Last Call, determining the process for registering a historic media type, and addressing unresolved pull requests and referencing issues for other drafts.

## Key Discussion Points

*   **Welcome New Co-chair**: Robert Sparks joined the CELLAR WG as a co-chair, with Michael St. Johns stepping back due to medical issues.
*   **Previous Meeting Minutes**: Minutes from the last meeting were reviewed and approved without comments.
*   **Errata for RFC 9559**:
    *   Discussion around the `font/x-otf` media type, which is historic and not an official media type. It was agreed that this should be registered with IANA as a historic media type using the standard media type template process, rather than an Errata or new document.
    *   Two pull requests (PRs 946 and 932) were identified as fixes for `RFC 9559`. PR 946 addresses underspecified queue time fields, and PR 932 allows more than one attachment link per track. These are considered non-controversial and will be submitted as errata once merged.
*   **`draft-ietf-cellar-tags` (tags-15)**:
    *   The document is largely ready for Working Group Last Call (WGLC).
    *   A pending item is the potential inclusion of a loudness tag based on ITU EBU R 128. This tag currently lacks definition and input from an expert. It was agreed that `tags-15` should proceed to WGLC, and if expert input is received before publication, the tag can be slipped in; otherwise, it can be added in a future document.
*   **`draft-ietf-cellar-codec` (codec-14)**:
    *   Three pull requests were highlighted:
        *   PR 937: Addresses an interpretation issue with SMPTE bits. Further review from participants (Steve, Jerome, Dave) is needed.
        *   PR 745: Requires rebase due to age.
        *   PR 446: Also requires rebase due to age, but the underlying idea remains valid.
    *   These PRs need to be resolved before `codec-14` can proceed to WGLC.
*   **`draft-ietf-cellar-chapter-codecs` (chapter-codecs-5)**:
    *   This document is pending further work, particularly for the Matroska.js JavaScript scripting codec.
    *   A significant issue is a normative reference to a non-public DVD specification. It was noted that this specification is effectively reverse-engineered in existing implementations, and the DVD Forum is dissolving, potentially releasing the specification. The working group needs to identify a publicly accessible normative reference or explore how reviewers can access the original.
    *   It was clarified that `chapter-codecs-5` is not necessarily tied to the progression of Matroska V5 and can be worked on in parallel.
*   **`draft-ietf-cellar-control` (control-5)**:
    *   This document was taken out of the main Matroska specification due to being underspecified and currently unused. It is not a priority and its future (finalization or dropping) is uncertain.
*   **FFV1 V4 Improvements**:
    *   An update was provided on ongoing work for FFV1 Version 4, including GPU encoder implementation and a work-in-progress GPU decoder.
    *   Discussions on proposed improvements are taking place on the `ffmpeg-devel` mailing list. The draft will be updated and published on the IETF datatracker once consensus is reached on these improvements. FFV1 Version 3 is already an RFC.
*   **Matroska V5**:
    *   Matroska V5 was mentioned as the future document for new work and additions, leveraging the modular nature of Matroska and the use of Markdown/XML for generation.

## Decisions and Action Items

*   **Decision**: The previous meeting minutes were approved.
*   **Decision**: `draft-ietf-cellar-tags` (tags-15) will proceed to Working Group Last Call (WGLC).
*   **Decision**: The `font/x-otf` media type will be registered as a historic media type via the IANA media type registration process.

*   **Action Item 2024-01-26-1 (Spencer)**: Draft and submit an IANA media type registration for `font/x-otf`, marking it as historic.
*   **Action Item 2024-01-26-2 (Steve, Jerome)**: Follow up with GitHub user `bb1g` for input on the ITU EBU R 128 loudness tag for `tags-15`.
*   **Action Item 2024-01-26-3 (Steve)**: Submit errata for `RFC 9559` based on the approved and merged PRs 946 and 932.
*   **Action Item 2024-01-26-4 (Steve, Jerome, Dave)**: Review PR 937 concerning SMPTE bit interpretation for `codec-14`.
*   **Action Item 2024-01-26-5 (Jerome)**: Rebase PRs 745 and 446 for `codec-14`.
*   **Action Item 2024-01-26-6 (Working Group)**: Investigate a publicly accessible normative reference for the DVD specification or explore liaison options for `draft-ietf-cellar-chapter-codecs` (chapter-codecs-5).
*   **Action Item 2024-01-26-7 (Michael)**: Follow up with the IETF Secretariat regarding Robert Sparks' organizational owner status for GitHub and DataTracker access.

## Next Steps

The Working Group will focus on:
*   Initiating Working Group Last Call for `draft-ietf-cellar-tags`.
*   Resolving outstanding pull requests for `draft-ietf-cellar-codec` to prepare it for Working Group Last Call.
*   Addressing the referencing issue for `draft-ietf-cellar-chapter-codecs`.
*   Continuing to monitor and contribute to FFV1 V4 development on the `ffmpeg-devel` mailing list.
*   Spencer to progress the `font/x-otf` IANA registration.