JVET-AN0060 AHG9: On the OMI SEI message in VSEI version 4 [M. M. Hannuksela, J. Boyce (Nokia)]

Chaired by S. Deshpande on 05 October 2025 from 09:45-10:00.

The following asserted bug fixes are proposed to the object mask information (OMI) SEI message:

1. In three instances, the for loop end condition is proposed to be fixed to use less than or equal to, i.e., "i <= omi_num_aux_pic_layer_minus1".

Already handled during the discussion JVET-AN0135, JVET-AN0161.

1. It is proposed that the derivation of OmiAuxSampleRangeDeltaMax[ i ] and the constraint related to consecutive tolerance value ranges are changed so that omi_aux_sample_value[ i ][ j ] + OmiAuxSampleRangeDeltaMax[ i ] indicates the greatest luma sample value that belongs to the mask area.

It is asserted that the range of exactly 1 sample value cannot be specified due to the calculation equations. Also it is asserted that the ranges can currently overlap.

It was commented that this was a mistake added during editing.

Further editorial simplification of the equation is possible and delegated to the editors.

Decision: Agreed.

1. It is asserted that a requirement for omi_mask_id_new_object_flag[ i ][ j ] to be equal to 1 could be understood to refer to decoding order, since it uses "is parsed for the first time" in its phrasing. The requirement for omi_mask_id_new_object_flag[ i ][ j ] to be equal to 1 is proposed to be phrased to refer to output order.

This is related to item 11 in JVET-AN0135.

It was commented that this approach and item 11 in JVET-AN0135 resolve the same issue.

Based on a non-proponent support, the language from item 11 of JVET-AN0135 is agreed (possibly further improved by the editors).

1. It is proposed to be clarified that omi_mask_depth[ i ][ j ] less than omi_mask_depth[ m ][ n ] indicates that the distance to the the j-th object of the i-th object mask auxiliary layer is less than the distance to the the n-th object of the m-th object mask auxiliary layer.

Decision: Agreed.

1. It is proposed to add: When omi_mask_depth[ i ][ j ] is not present, the object depth associated with the j-th object mask of the i-th object mask auxiliary layer is unknown or unspecified.

It was commented that there is an existing constraint that make sure the asserted problem never happensIn addition to the changes proposed above, the accompanying specification text document proposes other changes that are asserted to be editorial.

Delegated these to the editors.

JVET-AN0060 AHG9: On the OMI SEI message in VSEI version 4