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# Sound media

Store compressed and uncompressed audio data in QuickTime movies.

## Overview

Sound media is used to store compressed and uncompressed audio data in QuickTime movies. It has a media type of `'soun'`. This section describes the sound sample description and the storage format of sound files using various data formats.

## Topics

### Storing audio data

[Sound sample descriptions](/documentation/QuickTime-File-Format/Sound_sample_descriptions)

A sound sample description contains information that defines how to interpret sound media data.

[Sound sample description extensions](/documentation/QuickTime-File-Format/Sound_sample_description_extensions)

Extend sound sample descriptions by appending other atoms.

[Sound sample data](/documentation/QuickTime-File-Format/Sound_sample_data)

Sound sample formats that QuickTime supports.

[Audio priming-handling encoder delay in AAC](/documentation/QuickTime-File-Format/Appendix_G_Audio_priming_handling_encoder_delay_in_AAC)

Position a source audio signal in a sound track to handle encoder delay.


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