JVET-AL0326 AHG9/AHG18: Modification to error recovery SEI message [H. Tan (LGE), M. M. Hannuksela, J. Boyce (Nokia)] [late]

This contribution proposes some changes on top of the error recovery SEI message that is proposed in JVET-AL0069. The proposed changes are for incorporating temporal sub layers into the signalling of the proposed error recovery SEI message. It is asserted that the support for temporal sub layers is desirable as with it the error recovery SEI message allows encoder to use better reference pictures in the event of picture loss during transmission.

Further study – see the notes under JVET-AL0069 which is the basis.

CICP (4)

Contributions in this area were discussed during 0840–0945 Wednesday 2 April and 0920–0950 on Thursday 3 April 2025 (chaired by JRO).

JVET-AL0326 AHG9/AHG18: Modification to error recovery SEI message [H. Tan (LGE), M. M. Hannuksela, J. Boyce (Nokia)] [late]

See the notes in section 4.17.

Non-SEI HLS aspects (0)

Kept as template for future use.

Plenary meetings, joint meetings, BoG reports, and liaison communications

General

The following topics were discussed in JVET plenary Monday 31 March at 0820:

• Status of last meeting’s output documents
• Liaison communication –
  • Response to m72555 should be handled at SC29 level
  • to JPEG, regarding information on investigations of AI based I picture coding, mention relevance of bit-exact reconstruction investigations. E. Alshina will prepare a draft, review on Thursday morning
• Scheduling for the remaining week (further detail on scheduling is recorded in section 2.12).
• Review status from tracks and discussion on potential open issues
  • It was agreed to review documents with highest priority first.
• Review of documents at plenary level

Specific discussion on some general issues related to HLS was as follows:

…

MPEG information sharing meetings

Information sharing sessions with other WGs and AGs of the MPEG community were held on Monday 31 March 0500–0800, Wednesday 2 April 0500–0600, and Friday 4 April 2100–2300.

The status and plans for the work in the MPEG WGs and AGs was reviewed at these information sharing sessions.

Joint meetings

Joint sessions 1530-1730 Monday 31 March and 0500-0700 Thursday 3 April on next generation video standardization: JVET with ISO/IEC JTC 1/SC 29/WG 2 MPEG Technical Requirements, VCEG (ITU-T Q6/21), and ISO/IEC JTC 1/SC 29/AG 5 MPEG Visual Quality Assessment

Joint meeting sessions were held at 1530-1730 on Monday 31 March and 0500-0700 on Thursday 3 April on planning for potential next generation video coding standardization with capability beyond that of the VVC standard, and particularly to consider jointly issuing a Call for Evidence (CfE) toward developing such a standard.

These were joint sessions of JVET with ISO/IEC JTC 1/SC 29/WG 2 MPEG Technical Requirements, ITU-T Q6/21 (a.k.a. VCEG), and ISO/IEC JTC 1/SC 29/AG 5 MPEG Visual Quality Assessment.

This section is based on notes recorded by Gary Sullivan (Rapporteur of ITU-T Q6/21 and Chair of ISO/IEC JTC 1/SC 29). About 320 people attended these sessions.

Organization leaders present in one or both of these sessions included Jens-Rainer Ohm for JVET, Igor Curcio and Mary-Luc Champel of MPEG WG 2, Gary J. Sullivan, Justin Ridge, Yan Ye and Thomas Wiegand of VCEG, Mathias Wien of ISO/IEC JTC 1/SC 29/AG 5, and Jörn Ostermann of ISO/IEC JTC 1/SC 29/AG 2.

At the previous meeting, an updated document had been produced on “Preliminary draft of use cases and requirements for potential next-generation video coding standard beyond VVC capability”. It was issued as an annex to the Q6/21 meeting report and as WG 2 output document N 429.

Documents presented and discussed are listed below.

VCEG-BX08 / MPEG m72255 [J. Samuelsson-Allendes, S. Deshpande, T. Ikai (Sharp)] Gap analysis and suggested updates to next-generation video coding requirements draft

(This contribution was not registered for JVET.)

This contribution presents a summary of a gap analysis carried out with respect to existing MPEG/VCEG video coding standards. The contribution also provides suggestions for updates of “Preliminary draft of use cases and requirements for potential next-generation video coding standard beyond VVC capability” based on the gap analysis. This contribution is an update of the previous contribution JVET-AK0338.

There was an accompanying slide deck, which was requested to be uploaded to be available for study.

Discussed aspects included film grain and “digital noise”.

Discussion of the contribution resulted in edits to the prior “Preliminary draft of use cases and requirements for potential next-generation video coding standard beyond VVC capability” output document, and the result was agreed to be produced as an output of VCEG and MPEG WG 2.

JVET-AL0052 / VCEG-BX19 / MPEG m71802 [T. Solovyev, S. Ikonin, E. Alshina (Huawei)] Huawei comments on use case and requirements for next-generation video coding

This document analyses next generation video codec use case and requirements, suggests updates of the prior output on the subject which the proponent characterized as minor, and provides comments on the potential Call for Evidence.

Discussed aspects included:

• Loss/error concealment issue (addressed previously in review of VCEG-BX08 / MPEG m72255).
• Complexity / power consumption – on wearable devices, no action was taken at this time; this is for further study, although it is a valid concern. It was noted that power consumption can be difficult to estimate.
• Challenging content – it was commented that bit rate saving is useful regardless of the content type; a wide range of bit rates and wide range of content characteristics should be addressed, including challenging content
• Ultra-low end-to-end transmission latency, including 20 ms and lower
• Bit-exact reconstruction
• Measuring complexity

Results of the discussion were recorded in an edited copy of BX19, then integrated into the “Preliminary draft of use cases and requirements for potential next-generation video coding standard beyond VVC capability” output document, which was agreed to be produced as an output of VCEG and MPEG WG 2.

JVET-AL0235 / VCEG-BX20 / MPEG m72057 [B. Kroon, C. Varekamp (Philips] On the immersive requirements for the next generation video codec

This contribution aims to improve the requirements that relate to immersive use cases.

The draft “Preliminary draft of use cases and requirements for potential next-generation video coding standard beyond VVC capability” had two immersive use cases that were of interest to this contributor, who suggested that they require novel view synthesis:

• Immersive applications, such as virtual, augmented and mixed reality for communication, interaction and entertainment.
• Representation of content to allow the rendering of a viewpoint from a limited specified perspective

There are also some adjacent use cases that were said to be of interest:

• Single- and multiview representations for medical applications
• Low-delay 3D representation for remote communication

With these use cases in mind, the following content types were suggested to be relevant:

• Stereoscopic and multi-view content.
• Content with associated sample-based maps (e.g. for depth or alpha).
• Coding of alpha and/or depth components together with tristimulus colour components.

The proponent suggested that it is useful to be able to consider multiple partial views or planes with optional depth information and camera parameters.

After discussion, related changes were integrated into the “Preliminary draft of use cases and requirements for potential next-generation video coding standard beyond VVC capability” output document, which was agreed to be produced as an output of VCEG and MPEG WG 2.

Other aspects of discussion

AHG17 testing outside of the CTC was discussed, with a JVET BoG scheduled for Tuesday 1 April.

There was discussion of how to solicit and test constrained-complexity encoding. It was suggested to potentially have multiple tested complexity levels of a proposal.

There was also discussion of how to obtain evidence on other aspects such as loss resilience.

A possible dry run using the ECM was suggested for subjective study at the next meeting.

It was agreed for a preliminary Call for Evidence to be issued at this meeting. The target date for responses was discussed and suggested to be October, since the January 2026 meeting is planned to be online, and remarked that the Santa Eularia facilities of April–May 2026 may not have a lot of meeting space.

Soliciting information on parallelization was suggested.

JVET was asked to produce a draft Call for review in a second joint session to be held on Thursday. It should reference the draft requirements document.

The goal was agreed to be to produce an output draft requirements document as a public output of this meeting, and to further discuss this in the Thursday joint session.

Joint session Thursday 0500-0700

JVET-AL0047, produced by AHG17 and refined by a BoG, was reviewed. Additional notes about that document are found elsewhere in this report. Aspects discussed in the joint session included the following:

• Improved compression
  • Test cases were reviewed
• Fast Improved compression with runtime-constrained encoding
  • Similar test cases (a BoG output from F. Bossen was presented by E. Alshina and reviewed)
    • Comment re training set of NNs as well as other aspects
    • Why the full resolution requirement? It was commented that this could affect NN-based schemes. There was similar language in the other section. It was agreed to modify this to say that methods involving reduced resolution coding need to be described.
    • What about the suggested encoder runtime target – how will this be used? Remarks about multi-threading – multi-threading should be described.
    • It is not necessary to cover the full range of runtime variants. Submitting only a lower runtime variant, for example, should be fine.
    • It is not intended to be very restrictive about what evidence is to be submitted.
    • Are executables and cross-checking really needed? Some said encouragement should suffice. This is partly a matter of simplifying the logistics. It was suggested that this should be generally expected but not absolutely required.
    • Some aspects can remain under study – the intent is to issue a preliminary call.
    • Which version(s) are to be evaluated subjectively? It is not our intention to compare the submissions to each other, but rather to solicit evidence of potential, and testing capability is limited. There is not necessarily an intent to test everything that is submitted.
    • Perceptually optimized submissions are allowed; this should be discussed if not in the document yet. This could be interpreted as conflicting with having a constant-QP recommendation, but the request to have a description of such methods also means this is not prohibited. Optimizations that could apply to the anchor would be valuable to know about. It was agreed to just say that such schemes should be described.
    • “VTM default” means “VTM anchor”
• Other functionality (scalability, error robustness)

There may need to be an AHG preparatory pre-meeting in October.

A “dry run” for the planned evaluation testing is anticipated in July; it was agreed to mention this in the Draft CfE.

The CfE response deadline could be delayed if difficulties are encountered.

The timeline was agreed to be to expect responses for October.

Multipass aspects may need refinement.

Rate point tables are to be added.

The following main action plans were agreed:

• For JVET to issue a public draft joint CfE, referencing a public draft requirements document
• For WG 2 and VCEG to approve the public draft requirements document

BoGs (1)