Audio/Video Transport Core Maintenance (avtcore) Working Group
CHAIRS: Jonathan Lennox
Marius Kleidl

IETF 122 Agenda
Location: Bangkok, Thailand
Session: III
Room: Boromphimarn 3

Date: Thursday, March 20, 2025
Time: 15:00 - 16:30 Bangkok time

IETF 122 info: https://www.ietf.org/how/meetings/122
Meeting link: https://meetings.conf.meetecho.com/ietf122/?session=33886

Notes: https://notes.ietf.org/notes-ietf-122-avtcore
Slides:
https://docs.google.com/presentation/d/1E_XfsZbcSMyNl-p3L8jUk2HkD1hfqY35TPzr0aXcV0w/

Notetakers: Youngkwon Lim, Mo Zanaty

Preliminaries (Chairs, 15 min)

Note Well, Note Takers, Agenda Bashing, Draft status

Jonathan has presented Note Well, Participant Obligation highlighing IPR
disclosure, Code of Conducts, Meeting tips for In-person participants
and remote participants, Meeting resources, new co-chair Marius Kleidl
and honoring the former co-chair the late Bernard Aboba.

Jonathan has explained the status of the drafts.

Magnus has commented about ongoing work on RTP paylaod format registry
with mediaman.

Richard has expressed interest on the draft on sframe. Jonathan has
clarified that the draft will be parked for the moments and unparked
whenever the folks are ready to work on it.
Chair action: Park sframe.

Gorry noted that meeting slides are missing in the materials.

RTP Payload for V3C (Lauri Ilola, 5 min)

https://datatracker.ietf.org/doc/html/draft-ietf-avtcore-rtp-v3c

Lauri has presented the status of the draft.

RTP over QUIC (Mathis Engelbart, 10 min)

https://datatracker.ietf.org/doc/html/draft-ietf-avtcore-rtp-over-quic

Mathis has presented the status of the draft

Mathis has questioned about going to WGLC. Jonathan has clarified that
it was the previous agreement that SDP work needs to be finished before
WGLC but he now thinks it can be parallel.

SDP Offer/Answer for RTP over QUIC (Spencer Dawkins, 15 min)

https://datatracker.ietf.org/doc/html/draft-dawkins-avtcore-sdp-roq

Spencer has presented the progress of the draft.

Harald has commented that flow-ID and BUNDLE are at completely different
levels

Jonathan has commented that use of single flow-ID for a BUNDLE group
would be one way to go.

Harald questioned if anyone is not multiplexing RTP and RTCP. No
responses.

Spencer has explained that the authors are planning to produce -01
version before the AVTCORE interm with the request for WG adoption poll

Spencer asked if anyone else was interested in providing early review
comments, and Gurtej Chandok raised his hand.

RTP Payload for Haptics (Hyunsik Yang, 5 min)

https://datatracker.ietf.org/doc/html/draft-ietf-avtcore-rtp-haptics

Hyunsik has presented the updates of the draft

RTP Payload for V-DMC (Hyunsik Yang, 10 min)

https://datatracker.ietf.org/doc/html/draft-hsyang-avtcore-rtp-vdmc

Hyunsik has presented the draft

Hyunsik does not think it is reday for WG adoption yet

RTP Payload for APV (Youngkwon Lim, 10 min)

https://datatracker.ietf.org/doc/html/draft-lim-rtp-apv

Youngkwon presented goals of the draft and project. ISE is starting pub
review of version -03. New bitstream structure with PBUs and access
units, similar to other standards.

Mo asked if the marker bit applies to the entire AU or each layer.
Youngkwon clarified it applies to the entire AU.

Mo asked about ISE submission vs AVT WG RFC. Youngkwon clarified the
codec bitstream will be an ISE submission while the RTP payload format
will request AVT WG adoption.

Gurtej asked how to know when a tile is complete to decode it. Jonathan
answered when the fragment counter reaches 0.

Mo asked if the fragment counter results in high buffering and latency
at the encoder to know the number of fragments. Youngkwon clarified this
is often known up front before encoding, using filler to hit the known
target.

Automatic Corruption Detection (Erik Språng, 10 min)

https://datatracker.ietf.org/doc/draft-sprang-avtcore-corruption-detection

Erik has presented the draft

It has been clarified that the intention is to detect the bad decoder
implementation instead of error in the received bistream

Stephan asked if a new payload header or separate payload would be
better than a header extension. The author stated a header extension was
easiest to implement.

The authors considers WG adoption at the coming interim.

LTR feedback (Erik Språng, 5 min)

https://datatracker.ietf.org/doc/draft-sprang-avtcore-frame-acknowledgement

Erik has presented the draft

Magnus has question if this can be extended to tile level indication

Gurtej has commented that using frame ID is a good approach as timestamp
cannot specifically identify a frame if there are multiple layers.

Mo has commented that there are some vendor specific implementations but
no standard way.

If time permits: RTP Payload Format for Geometry-based Point Cloud Compression (Mathis Engelbart)

https://datatracker.ietf.org/doc/draft-engelbart-avtcore-rtp-gpcc/

Mathis has presented the draft

Wrapup and Next Steps (Chairs, 5 min)

Jonathan has noted that there might be an interim in half way between
the IETF123.

Marius has listed the action items: