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  "title" : "Base media information atom ('minf')"
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# Base media information atom ('minf')

An atom that stores the media information for media types such as timed metadata, text, MPEG, time code, and music.

## Overview

The base media information atom stores the media information for media types such as timed metadata, text, MPEG, time code, and music.

Media types that are derived from the base media handler may add other atoms within the base media information atom, as appropriate. The only media type that defines additional atoms is timecode media. See [Timed metadata media](/documentation/QuickTime-File-Format/Timed_metadata_media) and [Timecode media](/documentation/QuickTime-File-Format/Timecode_media) for more information about this media types.

The layout of a base media information atom is as follows:

|Data                                                                                                                       |Bytes    |
|---------------------------------------------------------------------------------------------------------------------------|---------|
|``doc://com.apple.qtff/documentation/quicktime-file-format/Base_media_information_atom/Size``                              |4 bytes  |
|``doc://com.apple.qtff/documentation/quicktime-file-format/Base_media_information_atom/Type`` = `'minf'`                   |4 bytes  |
|``doc://com.apple.qtff/documentation/quicktime-file-format/Base_media_information_atom/Base_media_information_header_atom``|`'gmhd'`‡|

‡ denotes required atom.

## Topics

### Data fields

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

A 32-bit integer that specifies the number of bytes in this base media information atom.

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

A 32-bit integer that identifies the atom type.

[`Base media information header atom`](/documentation/quicktime-file-format/Base_media_information_atom/Base_media_information_header_atom)

An atom that indicates that this media information atom pertains to a base media.


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