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# CMTimeMapping

A structure that maps a segment of a source time range to a target time range.

```
struct CMTimeMapping
```

## Topics

### Creating a Timebase

[`init(source:target:)`](/documentation/CoreMedia/CMTimeMapping/init(source:target:))

Creates a time mapping with a source and target time range.

[`init()`](/documentation/CoreMedia/CMTimeMapping/init())

Creates an empty time mapping.

### Accessing Time Ranges

[`source`](/documentation/CoreMedia/CMTimeMapping/source)

A time range on the source timeline.

[`target`](/documentation/CoreMedia/CMTimeMapping/target)

A time range on the target timeline.

### Type Properties

[`invalid`](/documentation/CoreMedia/CMTimeMapping/invalid)

An invalid time mapping.


---

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