audioTrackFormat

Description

The audioTrackFormat element corresponds to a single set of samples or data in a single track in a storage medium. It is used to describe what format the data is in, allowing a renderer to decode the signal correctly. It is referred from the audioStreamFormat element, which is used to identify the combination of tracks required to decode the track data successfully.

For PCM audio an audioStreamFormat will refer to a single audioTrackFormat and so the two elements are effectively describing the same thing. For coded audio, multiple audioTrackFormats will have to be combined in a single audioStreamFormat to generate decodable data.

Software that parses the model can start from either audioTrackFormat or audioStreamFormat. To allow for this flexibility audioTrackFormat can also refer back to the audioStreamFormat. However, it is a strict requirement that if this reference is used, the audioTrackFormat must refer to the same audioStreamFormat that is referring back to it.

Example

<audioTrackFormat audioTrackFormatID="AT_00010001_01"
                  audioTrackFormatName="PCM_FrontLeft"
                  formatDefinition="PCM" formatLabel="0001">
  <audioStreamFormatIDRef>AS_00010001</audioStreamFormatIDRef>
</audioTrackFormat>

Attributes

Attribute	Description	Example	Required
audioTrackFormatName	Name of the track	PCM_FrontLeft	Yes
audioTrackFormatID	ID for track. The yyyy digits of AT_yyyyxxxx_nn represent the type of audio contained in the track. The yyyyxxxx digits should match the audioStreamFormat yyyyxxxx digits. The nn digits represent the track number (starting at 1) within the stream.	AT_00010001_01	Yes
formatLabel	Descriptor of the format	0001	Optional
formatDefinition	Description of the format	PCM	Optional

* At least one of formatLabel or formatDefinition is required.

Sub-elements

Element	Description	Example	Quantity
audioStreamFormatIDRef	Reference to an audioStreamFormat	AS_00010001	1