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# start(imagesDirectory:configuration:)

Starts the session with the provided output image directory and optional checkpoint directory.

```
@MainActor func start(imagesDirectory: URL, configuration: ObjectCaptureSession.Configuration = Configuration())
```

## Parameters

`imagesDirectory`

A directory to save the images.

`configuration`

A configuration specifying session options.

## Discussion

The directory that `imagesDirectory` points to needs to be an empty and writable directory
or it is an error.
Likewise, if `checkpointDirectory` is provided, it needs to be empty if it already exists.
If the directory does not exist, it is created for you.
If it cannot be, the session moves to `.failed` state.

This call is only valid once on a newly created session.

---

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