# audioPackFormat

## Description

The audioPackFormat groups together one or more audioChannelFormats that belong together. Examples of audioPackFormats are ‘stereo’ and ‘5.1’ for channel-based formats. It can also contain references to other packs to allow nesting. The typeDefinition is used to define the type of channels described within the pack. The typeDefinition/typeLabel must match those in the referred audioChannelFormats. The sub-elements within audioPackFormat are dependent upon the typeDefinition or typeLabel of the audioPackFormat element.

## Common Attributes

Attribute Description Example Required Default
audioPackFormatID ID for the pack. The yyyy digits of AP_yyyyxxxx_represent the type of audio contained in the pack. AP_00010002 Yes -
audioPackFormatName Name of the pack stereo Yes -
typeLabel Descriptor of the type of channel 0001 Optional*
typeDefinition Description of the type of channel DirectSpeakers Optional*
importance Importance of a pack. Allows a renderer to discard a pack below a certain level of importance. 10 is the most important, 0 is the least. 10 Optional

## Common Sub-elements

Sub-element Description Example Quantity
audioChannelFormatIDRef Reference to an audioChannelFormat AC_00010001 0...*
audioPackFormatIDRef Reference to an audioPackFormat AP_00010002 0...*
absoluteDistance Absolute distance in metres 4.5 0 or 1