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# Track exclude from autoselection atom ('txas')

An atom that indicates not to automatically select this track.

## Overview

Some alternate tracks contain something other than a direct translation (or untranslated written form) of the primary content. Commentary tracks are one example. Don’t automatically select these tracks. The presence of the Track Exclude From Autoselection atom in a track indicates not to automatically select this track.

Ensure that such tracks have user-readable names that help users to identify the purpose of the track. These names are stored in one or more track name (`'tnam'`) atoms, each translated into a different language, within a user data (`'udta'`) atom within the `'trak'` atom.

The type of the Track Exclude From Autoselection atom is `'txas'`. This atom, if used, must be somewhere after the `'tkhd'` atom.

## Topics

### Data fields

[`Size`](/documentation/quicktime-file-format/Track_exclude_from_autoselection_atom/Size)

A 32-bit integer that specifies the number of bytes in the track exclude from autoselection atom.

[`Type`](/documentation/quicktime-file-format/Track_exclude_from_autoselection_atom/Type)

A 32-bit integer that identifies the atom type.


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