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# AVCompositionTrackFormatDescriptionReplacement

An object that represents a format description and its replacement.

```
class AVCompositionTrackFormatDescriptionReplacement
```

## Topics

### Managing format descriptions

[`originalFormatDescription`](/documentation/AVFoundation/AVCompositionTrackFormatDescriptionReplacement/originalFormatDescription)

The format description to replace.

[`replacementFormatDescription`](/documentation/AVFoundation/AVCompositionTrackFormatDescriptionReplacement/replacementFormatDescription)

The replacement format description.

## Relationships

### Conforms To

[`NSSecureCoding`](/documentation/Foundation/NSSecureCoding)

[`Equatable`](/documentation/Swift/Equatable)

[`NSCoding`](/documentation/Foundation/NSCoding)

[`CustomStringConvertible`](/documentation/Swift/CustomStringConvertible)

[`CVarArg`](/documentation/Swift/CVarArg)

[`Sendable`](/documentation/Swift/Sendable)

[`CustomDebugStringConvertible`](/documentation/Swift/CustomDebugStringConvertible)

[`Hashable`](/documentation/Swift/Hashable)

[`SendableMetatype`](/documentation/Swift/SendableMetatype)

[`NSObjectProtocol`](/documentation/ObjectiveC/NSObjectProtocol)

### Inherits From

[`NSObject-swift.class`](/documentation/ObjectiveC/NSObject-swift.class)

---

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