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# init(formatDescription:maxFrameDuration:minFrameDuration:validFrameDurations:)

Creates a stream format with a format description and frame durations.

```
@nonobjc convenience init(formatDescription: CMFormatDescription, maxFrameDuration: CMTime, minFrameDuration: CMTime, validFrameDurations: [CMTime]?)
```

## Parameters

`formatDescription`

The format of the samples that a stream delivers.

`maxFrameDuration`

The maximum frame duration the stream supports.

`minFrameDuration`

The minimum frame duration the stream supports.

`validFrameDurations`

A discrete set of supported frame durations.

## Discussion

---

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