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  "title" : "Video media information header atom ('vmhd')"
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# Video media information header atom ('vmhd')

An atom that defines specific color and graphics mode information.

## Overview

The layout of a media information header atom for video is as follows.

|Video media information header atom field                                                                     |Bytes|
|--------------------------------------------------------------------------------------------------------------|-----|
|``doc://com.apple.qtff/documentation/quicktime-file-format/Video_media_information_header_atom/Size``         |4    |
|``doc://com.apple.qtff/documentation/quicktime-file-format/Video_media_information_header_atom/Type``         |4    |
|``doc://com.apple.qtff/documentation/quicktime-file-format/Video_media_information_header_atom/Version``      |1    |
|``doc://com.apple.qtff/documentation/quicktime-file-format/Video_media_information_header_atom/Flags``        |3    |
|``doc://com.apple.qtff/documentation/quicktime-file-format/Video_media_information_header_atom/Graphics_mode``|2    |
|``doc://com.apple.qtff/documentation/quicktime-file-format/Video_media_information_header_atom/Opcolor``      |6    |

## Topics

### Data fields

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

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

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

A 32-bit integer that identifies the atom type.

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

A 1-byte specification of the version of this video media information header atom.

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

A 3-byte space for video media information flags.

[`Graphics mode`](/documentation/quicktime-file-format/Video_media_information_header_atom/Graphics_mode)

A 16-bit integer that specifies the transfer mode.

[`Opcolor`](/documentation/quicktime-file-format/Video_media_information_header_atom/Opcolor)

Three 16-bit values that specify the red, green, and blue colors for the transfer mode operation indicated in the graphics mode field.


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