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# Track aperture mode dimensions atom ('tapt')

A container atom that stores information for video correction in the form of three required atoms.

## Overview

This atom is optionally included in the track atom. The type of the track aperture mode dimensions atom is `‘tapt’`.

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

|Data                                                                                                                                      |Type    |
|------------------------------------------------------------------------------------------------------------------------------------------|--------|
|``doc://com.apple.qtff/documentation/quicktime-file-format/Track_aperture_mode_dimensions_atom/Size``                                     |4 bytes |
|``doc://com.apple.qtff/documentation/quicktime-file-format/Track_aperture_mode_dimensions_atom/Type`` = `'tapt'`                          |4 bytes |
|``doc://com.apple.qtff/documentation/quicktime-file-format/Track_aperture_mode_dimensions_atom/Track_clean_aperture_dimensions_atom``     |`'clef'`|
|``doc://com.apple.qtff/documentation/quicktime-file-format/Track_aperture_mode_dimensions_atom/Track_production_aperture_dimensions_atom``|`'prof'`|
|``doc://com.apple.qtff/documentation/quicktime-file-format/Track_aperture_mode_dimensions_atom/Track_encoded_pixels_dimensions_atom``     |`'enof'`|

## Topics

### Data fields

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

A 32-bit integer that specifies the number of bytes in the track aperture mode dimensions atom.

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

A 32-bit integer that identifies the atom type.

[`Track clean aperture dimensions atom`](/documentation/quicktime-file-format/Track_aperture_mode_dimensions_atom/Track_clean_aperture_dimensions_atom)

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

[`Track production aperture dimensions atom`](/documentation/quicktime-file-format/Track_aperture_mode_dimensions_atom/Track_production_aperture_dimensions_atom)

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

[`Track encoded pixels dimensions atom`](/documentation/quicktime-file-format/Track_aperture_mode_dimensions_atom/Track_encoded_pixels_dimensions_atom)

An atom that carries the pixel dimensions of the track’s encoded pixels.


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