==== AV1_video_descriptor

Defined by AOM in <<AOM-AV1>>.

[source,xml]
----
<AV1_video_descriptor
    version="uint7, required"
    seq_profile="uint3, required"
    seq_level_idx_0="uint5, required"
    seq_tier_0="uint1, required"
    high_bitdepth="bool, required"
    twelve_bit="bool, required"
    monochrome="bool, required"
    chroma_subsampling_x="bool, required"
    chroma_subsampling_y="bool, required"
    chroma_sample_position="unknown|vertical|colocated, required"
    HDR_WCG_idc="uint2, required"
    initial_presentation_delay_minus_one="uint4, optional"/>
----
