JVET-AP0117 AHG9: On danmu information SEI messages[ C. Kim, H. Tan, J. Lee, J. Nam, J. Lim, S. Kim (LGE)]

This contribution proposes changes that are asserted to improve various aspects for danmu information (DI) SEI message. The proposed items include:

• Item 1: Clarification of presentation precedence
• Item 2: Optional signalling of presentation priority
• Item 3: Signalling of semantic characteristics of danmu
• Item 4: Clarification of the semantic of di_default_params_present_flag
• Item 5: On the derivation of danmu start time

It was suggested that it isn’t needed to instruct the decoder to use start time to determine the display.

No action on item 1.

Agreed to item 2.

No action on item 3.

Item 4 was delegated to editors. For item 5, it was questioned if pruning of Danmus would occur, which the proposed change would disallow.

It was questioned if Danmus would be ordered by display start time. It would place a burden on the encoder to sort them to guarantee the order.

No action was taken on the ordering discussion.

JVET-AP0117 AHG9: On danmu information SEI messages