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# Object sample atom

An atom that describes a single object.

## Overview

An object sample atom describes a single object, including information about the default viewing angles and the view settings. The structure of an object sample atom is defined by the `QTVRObjectSampleAtom` data type:

```c
typedef struct VRObjectSampleAtom {
    UInt16                              majorVersion;
    UInt16                              minorVersion;
    UInt16                              movieType;
    UInt16                              viewStateCount;
    UInt16                              defaultViewState;
    UInt16                              mouseDownViewState;
    UInt32                              viewDuration;
    UInt32                              columns;
    UInt32                              rows;
    Float32                             mouseMotionScale;
    Float32                             minPan;
    Float32                             maxPan;
    Float32                             defaultPan;
    Float32                             minTilt;
    Float32                             maxTilt;
    Float32                             defaultTilt;
    Float32                             minFieldOfView;
    Float32                             fieldOfView;
    Float32                             defaultFieldOfView;
    Float32                             defaultViewCenterH;
    Float32                             defaultViewCenterV;
    Float32                             viewRate;
    Float32                             frameRate;
    UInt32                              animationSettings;
    UInt32                              controlSettings;
} VRObjectSampleAtom, *VRObjectSampleAtomPtr;
QT
QT
QT
```

## Topics

### Data fields

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

The major version number of the file format.

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

The minor version number of the file format.

[`movieType`](/documentation/quicktime-file-format/Object_sample_atom/movieType)

The movie controller type.

[`viewStateCount`](/documentation/quicktime-file-format/Object_sample_atom/viewStateCount)

The number of view states of the object.

[`defaultViewState`](/documentation/quicktime-file-format/Object_sample_atom/defaultViewState)

The 1-based index of the default view state.

[`mouseDownViewState`](/documentation/quicktime-file-format/Object_sample_atom/mouseDownViewState)

The 1-based index of the mouse-down view state.

[`viewDuration`](/documentation/quicktime-file-format/Object_sample_atom/viewDuration)

The total movie duration of all image frames contained in an object’s view.

[`columns`](/documentation/quicktime-file-format/Object_sample_atom/columns)

The number of columns in the object image array.

[`rows`](/documentation/quicktime-file-format/Object_sample_atom/rows)

The number of rows in the object image array.

[`mouseMotionScale`](/documentation/quicktime-file-format/Object_sample_atom/mouseMotionScale)

The mouse motion scale factor.

[`minPan`](/documentation/quicktime-file-format/Object_sample_atom/minPan)

The minimum pan angle, in degrees.

[`maxPan`](/documentation/quicktime-file-format/Object_sample_atom/maxPan)

The maximum pan angle, in degrees.

[`defaultPan`](/documentation/quicktime-file-format/Object_sample_atom/defaultPan)

The default pan angle, in degrees.

[`minTilt`](/documentation/quicktime-file-format/Object_sample_atom/minTilt)

The minimum tilt angle, in degrees.

[`maxTilt`](/documentation/quicktime-file-format/Object_sample_atom/maxTilt)

The maximum tilt angle, in degrees.

[`defaultTilt`](/documentation/quicktime-file-format/Object_sample_atom/defaultTilt)

The default tilt angle, in degrees.

[`minFieldOfView`](/documentation/quicktime-file-format/Object_sample_atom/minFieldOfView)

The minimum field of view to which the object can zoom.

[`fieldOfView`](/documentation/quicktime-file-format/Object_sample_atom/fieldOfView)

The image field of view, in degrees, for the entire object.

[`defaultFieldOfView`](/documentation/quicktime-file-format/Object_sample_atom/defaultFieldOfView)

The default field of view for the object.

[`defaultViewCenterH`](/documentation/quicktime-file-format/Object_sample_atom/defaultViewCenterH)

The default horizontal view center.

[`defaultViewCenterV`](/documentation/quicktime-file-format/Object_sample_atom/defaultViewCenterV)

The default vertical view center.

[`viewRate`](/documentation/quicktime-file-format/Object_sample_atom/viewRate)

The view rate.

[`frameRate`](/documentation/quicktime-file-format/Object_sample_atom/frameRate)

The frame rate.

[`animationSettings`](/documentation/quicktime-file-format/Object_sample_atom/animationSettings)

A set of 32-bit flags that encode information about the animation settings of the object.

[`controlSettings`](/documentation/quicktime-file-format/Object_sample_atom/controlSettings)

A set of 32-bit flags that encode information about the control settings of the object.


---

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