Note: This specification only provides the value of the itu_t_t35_terminal_provider_oriented_code that identifies the av1 film grain parameters metadata. The complete syntax of aom_itu_t_t35_payload( ) and the list of values for AOMedia itu_t_t35_terminal_provider_oriented_code are defined in the AOMedia metadata registry specification.
I was a bit confused about this note:
because this spec actually defines the syntax for the generic AOM T.35 payload. Perhaps the idea would be to move the syntax proposed in https://github.com/AOMediaCodec/afgs1-spec/issues/22 to that AOMedia metadata registry specification?