JVET-AM0165 AHG9: On value range and reserved values for syntax elements in VSEI v4 [J. Nam, H. Tan, J. Lee, C. Kim, J. Lim, S. Kim (LGE)]

JVET-AM0165 also relates to the EOI, MI, TDI, and IFM messages

(Related to SPTI SEI message)

1. On value range of spti_source_type in SPTI SEI

(Related to MI SEI message)

2. On value range of mi_modality_type in MI SEI

3. On reserved value of mi_modality_type in MI SEI

(Related to EOI SEI message)

4. On reserved value of eoi_type in EOI SEI

5. On reserved value of eoi_object_based_idc in EOI SEI

6. On reserved value of eoi_privacy_protection_method_idc in EOI SEI

7. On reserved value of eoi_privacy_info_type in EOI SEI

(Related to IFM SEI message)

8. On reserved value of ifm_type_id[ i ] in IFM SEI

(Related to TDI SEI message)

9. On reserved value of tdi_descr_purpose in TDI SEI

10. On reserved value of tdi_descr_id in TDI SEI

Regarding item 1, in the current design of source picture timing information (SPTI) SEI message, the syntax element spti_source_type is defined using bitmask operations in the range of 0x01 to 0x80, which means there are 8 bits out of the 16 bits allocated for this signalling have been specified. However, the current semantics of spti_source_type specify that its value range is from 0 to 127, and the decoder is designed to ignore spti_source_type values from 128 to 255.

Item 2 is related to JVET-AM0047 item 1. No action.

Item 3 proposes typical language regarding reserve values, which was missing.

Item 4 clarifies the behavior of decoders regarding reserved values of eoi_type.

Item 5 clarifies the behavior of...

JVET-AN0002 JVET AHG report: Draft text and test model algorithm description editing (AHG2) [B. Bross, C. Rosewarne (co-chairs), F. Bossen, A. Browne, S. Kim, S. Liu, J.-R. Ohm, G. J. Sullivan, A. Tourapis, Y.-K. Wang, Y. Ye (vice chairs)]

Output documents produced

JVET-AM0181 AHG9: Proposed new SEI message on localization and mapping [G. Teniou, S. Wenger, A. Hinds, J. Ricard (Tencent), Louis Kerofsky, Yong He, Shuai Zhao (Qualcomm)]

This document proposes a new SEI message designed to support the 3d model creation from 2d video streams. The proposed SEI message conveys essential metadata such as camera intrinsic (focal length, principal point, …) parameters and camera extrinsic (position and orientation) parameters. This metadata is crucial for algorithms that create 3D models such as 3d Gaussian Splatting (3DGS) and to assist the rendering process.

The radial distortion aspect of this SEI message is a subset of what is provided in the Lens optical correction (LOC) SEI.

It was questioned why 3dmr_camera_id is included in the intrinsic parameters.

The focal length is expressed in pixels, which should be for the capture resolution, which may not be the same as the coded picture.

This condition is problematic for future extensibility: if( 3dmr_camera_model ! = 1 )

It was suggested that gaussian splat coding may benefit from having the same information, so there should be some coordination.

Differences between JVET-AM0103 and this contribution:

• presence of the intrinsic parameters in this contribution
• the coordinate system in JVET-AM0103
• depth range
• more models for the extrinsic parameters is JVET-AM0103

There is some support for the providing a solution for this use case.

Further discussion requested after side activity to try to merge JVET-AM0103 and JVET-AM0181.

Further discussed at 1135 on 1 July 2025.

The message is renamed...