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# kVTCompressionPropertyKey_ExpectedFrameRate

The expected frame rate, if known.

```
let kVTCompressionPropertyKey_ExpectedFrameRate: CFString
```

## Discussion

The frame rate is measured in frames per second.  This setting is not used to control the frame rate; it’s provided as a hint to the video encoder so that it can set up internal configuration before compression begins. The actual frame rate depends on frame durations and may vary.

By default, this value is `0`, indicating the frame rate is unknown.

---

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