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# Track load settings atom ('load')

An atom that indicates how the track is to be used in its movie.

## Overview

Track load settings atoms contain information that indicates how the track is to be used in its movie. Applications that read QuickTime files can use this information to process the
movie data more efficiently. Track load settings atoms have an atom type value of `'load'`.

The layout of a track load settings atom is as follows.

|Track load settings atom                                                                                |Bytes|
|--------------------------------------------------------------------------------------------------------|-----|
|``doc://com.apple.qtff/documentation/quicktime-file-format/Track_load_settings_atom/Size``              |4    |
|``doc://com.apple.qtff/documentation/quicktime-file-format/Track_load_settings_atom/Type``              |4    |
|``doc://com.apple.qtff/documentation/quicktime-file-format/Track_load_settings_atom/Preload_start_time``|4    |
|``doc://com.apple.qtff/documentation/quicktime-file-format/Track_load_settings_atom/Preload_duration``  |4    |
|``doc://com.apple.qtff/documentation/quicktime-file-format/Track_load_settings_atom/Preload_flags``     |4    |
|``doc://com.apple.qtff/documentation/quicktime-file-format/Track_load_settings_atom/Default_hints``     |4    |

## Topics

### Data fields

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

A 32-bit integer that specifies the number of bytes in this track load settings atom.

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

A 32-bit integer that identifies the atom type.

[`Preload start time`](/documentation/quicktime-file-format/Track_load_settings_atom/Preload_start_time)

A 32-bit integer specifying the starting time, in the movie’s time coordinate system, of a segment of the track that is to be preloaded.

[`Preload duration`](/documentation/quicktime-file-format/Track_load_settings_atom/Preload_duration)

A 32-bit integer specifying the duration, in the movie’s time coordinate system, of a segment of the track that is to be preloaded.

[`Preload flags`](/documentation/quicktime-file-format/Track_load_settings_atom/Preload_flags)

A 32-bit integer containing flags governing the preload operation.

[`Default hints`](/documentation/quicktime-file-format/Track_load_settings_atom/Default_hints)

A 32-bit integer containing playback hints.


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