Bruce’s Shorts | 4.6 - What is SMPTE MCA and why do I need it?

In the fourth season of ‘Bruce’s Shorts’, Bruce Devlin takes a look at the Interoperable Master Format (IMF). Ever wondered why we don’t label the audio channels in files? This episode will help you find out.

Traditionally, audio channel designation was a house standard defined in a broadcaster's delivery specification. This has generally led to the need the remap the audio tracks at the ingest of files to a facility. Why isn't there a common way of labelling the audio? What track goes where and what language is being used?

That's where the Multi-Channel Audio (MCA) labelling specification comes in. MCA works at three levels:

  • channel labels
  • group of channel labels
  • group of group labels

The MCA labelling specification is SMPTE ST-377-4, a labeling framework for multichannel audio essence in MXF file structures. It specifies the basic object model, structures and metadata items for the MCA Labeling Framework.

This standard enables text-based representation of Multichannel Audio Labels and defines one such representation.

IMF is standardised by the SMPTE as ST 2067.

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