docs/content/docs/preview-output.mdx
import { Tab, Tabs } from 'fumadocs-ui/components/tabs'
The CameraPreviewOutput allows streaming a Camera feed into a Preview, which may be connected to a Preview View to display a Camera feed to the user.
<Tabs items={["<Camera /> (view)", "useCamera(...) (hook)", "CameraSession (imperative)"]} groupId="api-style" persist> <Tab value="<Camera /> (view)">
<Tab value="useCamera(...) (hook)"> ```tsx function App() { const device = useCameraDevice('back') // [!code ++] const previewOutput = usePreviewOutput()[!NOTE] The
</Tab><Camera />view already creates aCameraPreviewOutput(+<NativePreviewView />) for you, automatically.
const camera = useCamera({ isActive: true, device: device, // [!code ++] outputs: [previewOutput], }) }
</Tab>
<Tab value="CameraSession (imperative)">
```tsx
const session = await VisionCamera.createCameraSession(false)
const device = await getDefaultCameraDevice('back')
// [!code ++]
const previewOutput = VisionCamera.createPreviewOutput()
await session.configure([
{
input: device,
outputs: [
// [!code ++]
{ output: previewOutput, mirrorMode: 'auto' }
],
constraints: []
}
], {})
await session.start()
To display the Camera feed to the user, you must connect the CameraPreviewOutput to a <NativePreviewView />:
function App() {
const previewOutput = usePreviewOutput()
return (
// [!code ++:4]
<NativePreviewView
style={StyleSheet.absoluteFill}
previewOutput={previewOutput}
/>
)
}
See "Views: <NativePreviewView />" for more information about <NativePreviewView />.