react-native-vision-camera/docs/docs/guides/CAPTURING.mdx

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---
id: capturing
title: Taking Photos/Recording Videos
sidebar_label: Taking Photos/Recording Videos
---
import useBaseUrl from '@docusaurus/useBaseUrl';
<div>
<svg xmlns="http://www.w3.org/2000/svg" width="283" height="535" style={{ float: 'right' }}>
<image href={useBaseUrl("img/demo_capture.gif")} x="18" y="33" width="247" height="469" />
<image href={useBaseUrl("img/frame.png")} width="283" height="535" />
</svg>
</div>
## Camera Actions
The Camera provides certain actions using member functions which are available by using a [ref object](https://reactjs.org/docs/refs-and-the-dom.html):
```tsx
function App() {
const camera = useRef<Camera>(null)
// ...
return (
<Camera
ref={camera}
{...cameraProps}
/>
)
}
```
The most important actions are:
* [Taking Photos](#taking-photos)
- [Taking Snapshots](#taking-snapshots)
* [Recording Videos](#recording-videos)
## Taking Photos
To take a photo you first have to enable photo capture:
```tsx
<Camera {...props} photo={true} />
```
Then, simply use the Camera's [`takePhoto(...)`](/docs/api/classes/Camera#takephoto) function:
```ts
const photo = await camera.current.takePhoto({
flash: 'on'
})
```
You can customize capture options such as [automatic red-eye reduction](/docs/api/interfaces/TakePhotoOptions#enableautoredeyereduction), [automatic image stabilization](/docs/api/interfaces/TakePhotoOptions#enableautostabilization), [combining images from constituent physical camera devices](/docs/api/interfaces/TakePhotoOptions#enablevirtualdevicefusion) to create a single high quality fused image, [enable flash](/docs/api/interfaces/TakePhotoOptions#flash), [prioritize speed over quality](/docs/api/interfaces/TakePhotoOptions#qualityprioritization) and more using the `options` parameter. (See [`TakePhotoOptions`](/docs/api/interfaces/TakePhotoOptions))
This function returns a [`PhotoFile`](/docs/api/interfaces/PhotoFile) which contains a [`path`](/docs/api/interfaces/PhotoFile#path) property you can display in your App using an `<Image>` or `<FastImage>`.
### Taking Snapshots
Compared to iOS, Cameras on Android tend to be slower in image capture. If you care about speed, you can use the Camera's [`takeSnapshot(...)`](/docs/api/classes/Camera#takesnapshot) function (Android only) which simply takes a snapshot of the Camera View instead of actually taking a photo through the Camera lens.
```ts
const snapshot = await camera.current.takeSnapshot({
quality: 85,
skipMetadata: true
})
```
:::note
While taking snapshots is faster than taking photos, the resulting image has way lower quality. You can combine both functions to create a snapshot to present to the user at first, then deliver the actual high-res photo afterwards.
:::
:::note
feat: Frame Processors for Android (#196) * Create android gradle build setup * Fix `prefab` config * Add `pickFirst **/*.so` to example build.gradle * fix REA path * cache gradle builds * Update validate-android.yml * Create Native Proxy * Copy REA header * implement ctor * Rename CameraViewModule -> FrameProcessorRuntimeManager * init FrameProcessorRuntimeManager * fix name * Update FrameProcessorRuntimeManager.h * format * Create AndroidErrorHandler.h * Initialize runtime and install JSI funcs * Update FrameProcessorRuntimeManager.cpp * Update CameraViewModule.kt * Make CameraView hybrid C++ class to find view & set frame processor * Update FrameProcessorRuntimeManager.cpp * pass function by rvalue * pass by const && * extract hermes and JSC REA * pass `FOR_HERMES` * correctly prepare JSC and Hermes * Update CMakeLists.txt * add missing hermes include * clean up imports * Create JImageProxy.h * pass ImageProxy to JNI as `jobject` * try use `JImageProxy` C++ wrapper type * Use `local_ref<JImageProxy>` * Create `JImageProxyHostObject` for JSI interop * debug call to frame processor * Unset frame processor * Fix CameraView native part not being registered * close image * use `jobject` instead of `JImageProxy` for now :( * fix hermes build error * Set enable FP callback * fix JNI call * Update CameraView.cpp * Get Format * Create plugin abstract * Make `FrameProcessorPlugin` a hybrid object * Register plugin CXX * Call `registerPlugin` * Catch * remove JSI * Create sample QR code plugin * register plugins * Fix missing JNI binding * Add `mHybridData` * prefix name with two underscores (`__`) * Update CameraPage.tsx * wrap `ImageProxy` in host object * Use `jobject` for HO box * Update JImageProxy.h * reinterpret jobject * Try using `JImageProxy` instead of `jobject` * Update JImageProxy.h * get bytes per row and plane count * Update CameraView.cpp * Return base * add some docs and JNI JSI conversion * indent * Convert JSI value to JNI jobject * using namespace facebook * Try using class * Use plain old Object[] * Try convert JNI -> JSI * fix decl * fix bool init * Correctly link folly * Update CMakeLists.txt * Convert Map to Object * Use folly for Map and Array * Return `alias_ref<jobject>` instead of raw `jobject` * fix JNI <-> JSI conversion * Update JSIJNIConversion.cpp * Log parameters * fix params index offset * add more test cases * Update FRAME_PROCESSORS_CREATE_OVERVIEW.mdx * fix types * Rename to example plugin * remove support for hashmap * Try use HashMap iterable fbjni binding * try using JReadableArray/JReadableMap * Fix list return values * Update JSIJNIConversion.cpp * Update JSIJNIConversion.cpp * (iOS) Rename ObjC QR Code Plugin to Example Plugin * Rename Swift plugin QR -> Example * Update ExamplePluginSwift.swift * Fix Map/Dictionary logging format * Update ExampleFrameProcessorPlugin.m * Reconfigure session if frame processor changed * Handle use-cases via `maxUseCasesCount` * Don't crash app on `configureSession` error * Document "use-cases" * Update DEVICES.mdx * fix merge * Make `const &` * iOS: Automatically enable `video` if a `frameProcessor` is set * Update CameraView.cpp * fix docs * Automatically fallback to snapshot capture if `supportsParallelVideoProcessing` is false. * Fix lookup * Update CameraView.kt * Implement `frameProcessorFps` * Finalize Frame Processor Plugin Hybrid * Update CameraViewModule.kt * Support `flash` on `takeSnapshot()` * Update docs * Add docs * Update CameraPage.tsx * Attribute NonNull * remove unused imports * Add Android docs for Frame Processors * Make JNI HashMap <-> JSI Object conversion faster directly access `toHashMap` instead of going through java * add todo * Always run `prepareJSC` and `prepareHermes` * switch jsc and hermes * Specify ndkVersion `21.4.7075529` * Update gradle.properties * Update gradle.properties * Create .aar * Correctly prepare android package * Update package.json * Update package.json * remove `prefab` build feature * split * Add docs for registering the FP plugin * Add step for dep * Update CaptureButton.tsx * Move to `reanimated-headers/` * Exclude reanimated-headers from cpplint * disable `build/include_order` rule * cpplint fixes * perf: Make `JSIJNIConversion` a `namespace` instead of `class` * Ignore runtime/references for `convert` funcs * Build Android .aar in CI * Run android build script only on `prepack` * Update package.json * Update package.json * Update build-android-npm-package.sh * Move to `yarn build` * Also install node_modules in example step * Update validate-android.yml * sort imports * fix torch * Run ImageAnalysis on `FrameProcessorThread` * Update Errors.kt * Add clean android script * Upgrade reanimated to 2.3.0-alpha.1 * Revert "Upgrade reanimated to 2.3.0-alpha.1" This reverts commit c1d3bed5e03728d0b5e335a359524ff4f56f5035. * :warning: TEMP FIX: hotfix reanimated build.gradle * Update CameraView+TakeSnapshot.kt * :warning: TEMP FIX: Disable ktlint action for now * Update clean.sh * Set max heap size to 4g * rebuild lockfiles * Update Podfile.lock * rename * Build lib .aar before example/
2021-06-27 04:37:54 -06:00
The `takeSnapshot` function also works with `photo={false}`. For this reason VisionCamera will automatically fall-back to snapshot capture if you are trying to use more use-cases than the Camera natively supports. (see ["The `supportsParallelVideoProcessing` prop"](/docs/guides/devices#the-supportsparallelvideoprocessing-prop))
:::
## Recording Videos
To start a video recording you first have to enable video capture:
```tsx
<Camera
{...props}
video={true}
audio={true} // <-- optional
/>
```
Then, simply use the Camera's [`startRecording(...)`](/docs/api/classes/Camera#startrecording) function:
```ts
camera.current.startRecording({
flash: 'on',
onRecordingFinished: (video) => console.log(video),
onRecordingError: (error) => console.error(error),
})
```
For any error that occured _while recording the video_, the `onRecordingError` callback will be invoked with a [`CaptureError`](/docs/api/classes/CameraCaptureError) and the recording is therefore cancelled.
To stop the video recording, you can call [`stopRecording(...)`](/docs/api/classes/Camera#stoprecording):
```ts
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await camera.current.stopRecording()
```
Once a recording has been stopped, the `onRecordingFinished` callback passed to the `startRecording` function will be invoked with a [`VideoFile`](/docs/api/interfaces/VideoFile) which you can then use to display in a [`<Video>`](https://github.com/react-native-video/react-native-video) component.
<br />
#### 🚀 Next section: [Frame Processors](frame-processors)