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# Closed captioning media

Store closed captioning for QuickTime movies.

## Overview

A closed caption media track contains text data used for closed captioning in QuickTime movies. It has a media type of `'clcp'`. Closed captions are used to display the audio portions of a movie as text. They transcribe dialog and indicate other sounds.

Other tracks can identify this track as being a related closed captioning track by using the `'clcp'` track reference to refer to this track.

Like other media data tracks, a closed caption track should include a language code and an extended language tag atom.

## Topics

### Storing closed captioning

[`Closed captioning sample description`](/documentation/quicktime-file-format/Closed_captioning_sample_description)

An atom that defines how to interpret closed captioning media data.

[`Closed captioning sample data ('cdat')`](/documentation/quicktime-file-format/Closed_captioning_sample_data)

A sequence of one or more atoms that store closed captioning sample data.

[Including multiple closed-caption tracks](/documentation/QuickTime-File-Format/Including_multiple_closed-caption_tracks)

Include multiple closed-caption tracks in a movie.


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