==== audio_component_descriptor

Defined by ARIB in <<ARIB-B10J>>.

[source,xml]
----
<audio_component_descriptor
    stream_content="uint4, default=2"
    component_type="uint8, required"
    component_tag="uint8, required"
    stream_type="uint8, required"
    simulcast_group_tag="uint8, default=0xFF"
    main_component="bool, default=true"
    quality_indicator="uint2, required"
    sampling_rate="uint3, required"
    ISO_639_language_code="char3, required"
    ISO_639_language_code_2="char3, optional"
    text="string, optional"/>
----
