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# addVideoInputDevice

> Adds or replaces the primary video input device with optional constraints or stream.

```ts
addVideoInputDevice(__namedParameters?): Promise<void>
```

Adds or replaces the primary video input device with optional constraints or stream.

## **Parameters**

**`__namedParameters`** `{ constraints?: MediaTrackConstraints; stream?: MediaStream; }`

Capture options: either explicit `constraints` or a pre-acquired `stream`. See [`MediaTrackConstraints`](https://developer.mozilla.org/en-US/docs/Web/API/MediaTrackConstraints) and [`MediaStream`](https://developer.mozilla.org/en-US/docs/Web/API/MediaStream).

---

## **Returns**

`Promise<void>`

## **Examples**

```ts
await selfParticipant.addVideoInputDevice(__namedParameters);
```

> Adds or replaces the primary video input device with optional constraints or stream.