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# nominalFrameRate

The frame rate of the track in frames per second, as a 32-bit floating point number.

```
var nominalFrameRate: Float32 { get set }
```

## Discussion

For field-based video tracks that carry one field per media sample, the value of this property is the field rate, not the frame rate. `MediaToolbox` uses this property to calculate the maximum playback speed.

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