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# Node header atom ('ndhd')

An atom that describes the type and ID of a node, as well as other information about the node.

## Overview

A node header atom is a leaf atom that describes the type and ID of a node, as well as other information about the node. Its atom type is `kQTVRNodeHeaderAtomType` (`'ndhd'`).

The structure of a node header atom is defined by the QTVRNodeHeaderAtom data type:

```c
typedef struct VRNodeHeaderAtom {
    UInt16                              majorVersion;
    UInt16                              minorVersion;
    OSType                              nodeType;
    QTAtomID                            nodeID;
    QTAtomID                            nameAtomID;
    QTAtomID                            commentAtomID;
    UInt32                              reserved1;
    UInt32                              reserved2;
} VRNodeHeaderAtom, *VRNodeHeaderAtomPtr;
```

## Topics

### Data fields

[`majorVersion`](/documentation/quicktime-file-format/Node_header_atom/majorVersion)

The major version number of the file format.

[`minorVersion`](/documentation/quicktime-file-format/Node_header_atom/minorVersion)

The minor version number of the file format.

[`nodeType`](/documentation/quicktime-file-format/Node_header_atom/nodeType)

The node type.

[`nodeID`](/documentation/quicktime-file-format/Node_header_atom/nodeID)

The node ID.

[`nameAtomID`](/documentation/quicktime-file-format/Node_header_atom/nameAtomID)

The ID of the string atom that contains the name of the node.

[`commentAtomID`](/documentation/quicktime-file-format/Node_header_atom/commentAtomID)

The ID of the string atom that contains a comment for the node.

[`reserved1`](/documentation/quicktime-file-format/Node_header_atom/reserved1)

Reserved.

[`reserved2`](/documentation/quicktime-file-format/Node_header_atom/reserved2)

Reserved.


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