Session Date/Time: 24 May 2022 19:00

CELLAR

Summary

The CELLAR working group met to discuss the status of its active drafts: Matroska, FLAC, and FFV1. Key points included confirmation of working group consensus for Matroska, progress on the FLAC specification and an important discussion around container mappings (specifically MP4), and the need to address the expiring FFV1 draft. Milestones were also briefly reviewed, with an acknowledgment that the current FLAC milestone is likely unrealistic.

Key Discussion Points

Matroska: The draft has been updated following working group last call. Spencer and Steve noted they are behind on the review for the shepherding write-up. Working group consensus was confirmed for the document, pending this final review and write-up.
FLAC: Martin reported significant progress. A key issue, originally raised by Jerome, is the inclusion of container mappings (e.g., for Ogg, Matroska, and MP4) within the FLAC RFC.
- For Matroska, a reference to existing RFCs or IDs is sufficient.
- For MP4, there is no IANA registry; Apple maintains a separate registry. The existing draft mapping for FLAC in MP4 is extensive (8-10 pages) and considered experimental by some.
- There was discussion on whether MP4 mappings should be part of the FLAC RFC, a separate IETF document, or purely an external reference. Steve suggested it might be better as a separate document, as it describes how to put FLAC into MP4, not the FLAC format itself.
- The challenge of obtaining an identifier for FLAC within Apple's MP4 registry was discussed, with the potential need to contact Apple and the IETF AD for guidance on the process (e.g., whether a stable document or publication is required for allocation).
- Martin mentioned reaching out to W3C contacts who had commented on a FLAC issue regarding this but had not yet received a reply.
FFV1: The draft is nearing expiration, with its last post in November. It was noted as needing attention.
Milestones: The working group acknowledged that the current July milestone for FLAC is likely unrealistic, and a more realistic timeline needs to be discussed once the document is closer to completion. The area director had recently returned from leave, which impacted prior milestone discussions.
Upcoming Events: The "No Time To Wait" event was announced for October 26-28 in the Netherlands, conflicting with RIPE 85.

Decisions and Action Items

Decision: Working group consensus has been reached for the Matroska document.
Action Item (Chairs - Steve and Spencer): Complete the shepherding review and write-up for the Matroska document.
Action Item (Martin): Continue to investigate the MP4 container mapping for FLAC. Specifically:
- Open (or update existing) an issue on the issue tracker for the MP4 container mapping.
- Attempt to contact Apple regarding the allocation of an identifier for FLAC within their MP4 registry.
- Include Steve in communications regarding the Apple MP4 registry process.
Decision: FFV1 will be the primary focus for the June working group call to address its expiring status.

Next Steps

The next CELLAR WG meeting is scheduled for June 28th.
Prioritize review and discussion of the FFV1 draft for the upcoming June meeting.
Continue work on the FLAC document, with a focus on resolving the container mapping discussions and addressing the MP4 registry issue.
The chairs will aim to finalize the Matroska shepherding write-up.
A more realistic milestone for FLAC will be discussed in a future meeting.