AC-3 AudioDescriptor [ATSC Semantics]

The ATSC AC-3 descriptor is a descriptor that should be located in the Program Map Table of an ATSC program service as well as in the Event Information Table of any program event currently being transmitted in a virtual channel.

Pursuant to the ATSC A/53 specification, the AC-3 descriptor is mandatory to describe ATSC elementary streams that carry AC-3 audio.  As the Federal Communications Commission has incorporated A/52 and A/53 by reference into section 73.8000 of it's rules, this is ___ for all U.S. digital broadcast television stations.

The ATSC AC-3 descriptor is listed in Table 6.25a and b of the ATSC A/65 specification, but the descriptor is defined in Annex A of the ATSC A/52 (AC-3) specification.

Note: the below only includes elements appropriate to ATSC A/52 AC-3, and reflects the AC-3_audio_stream_descriptor as defined in ATSC A/52B (2005)