JVET-AP0151 AHG9: On the default parameters in the DI SEI message [S. Xie, P. Wu, Y. Gao, W. Niu, Y. Bai (ZTE)]

This contribution proposes to modify the syntax structure for the default parameters application to improve the design and flexibility of the Danmu Information (DI) SEI message in the current VSEI TuC.

The proposal will save bitrate in some cases when only some of the types of parameters change, but will have a small increase in bitrate for sending additional flags in other cases.

We don’t have a good understanding of the relative frequency of this.

Further study to provide some information about expected usage of changing some parameters but not others, and some bitrate savings estimates.