JVET-P0984: Subpicture Level Information SEI
Proper initialization depends on subpictures being supported in the SPS. Unfortuntely the subpicture implementation of JVET-O1143 is still not available.
We could achieve some independence with #775, which may not be easy to resolve between meeting.
We suggest merging the MR as is and will provide initialisation/config file support in a separate MR after JVET-O1143 is available.