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  "title" : "Track clean aperture dimensions atom ('clef')"
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# Track clean aperture dimensions atom ('clef')

An atom that carries the pixel dimensions of the track’s clean aperture.

## Overview

The type of the track clean aperture dimensions atom is `‘clef’`.

The layout of a track clean aperture dimensions atom is as follows.

|Data field                                                                                               |Bytes|
|---------------------------------------------------------------------------------------------------------|-----|
|``doc://com.apple.qtff/documentation/quicktime-file-format/Track_clean_aperture_dimensions_atom/Size``   |4    |
|``doc://com.apple.qtff/documentation/quicktime-file-format/Track_clean_aperture_dimensions_atom/Type``   |4    |
|``doc://com.apple.qtff/documentation/quicktime-file-format/Track_clean_aperture_dimensions_atom/Version``|1    |
|``doc://com.apple.qtff/documentation/quicktime-file-format/Track_clean_aperture_dimensions_atom/Flags``  |3    |
|``doc://com.apple.qtff/documentation/quicktime-file-format/Track_clean_aperture_dimensions_atom/Width``  |4    |
|``doc://com.apple.qtff/documentation/quicktime-file-format/Track_clean_aperture_dimensions_atom/Height`` |4    |

## Topics

### Data fields

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

A 32-bit integer that specifies the number of bytes in the atom.

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

A 32-bit integer that identifies the atom type.

[`Version`](/documentation/quicktime-file-format/Track_clean_aperture_dimensions_atom/Version)

A 1-byte specification of the version of this atom.

[`Flags`](/documentation/quicktime-file-format/Track_clean_aperture_dimensions_atom/Flags)

Three bytes that are reserved for the atom flags.

[`Width`](/documentation/quicktime-file-format/Track_clean_aperture_dimensions_atom/Width)

A 32-bit fixed-point number that specifies the width of the track clean aperture in pixels.

[`Height`](/documentation/quicktime-file-format/Track_clean_aperture_dimensions_atom/Height)

A 32-bit fixed-point number that specifies the height of the track clean aperture in pixels.


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