An app can record the video or audio that is being played from another app. Such
apps must handle the
[`MediaProjection`](https://developer.android.com/reference/android/media/projection/MediaProjection) token
correctly. This page explains how. It also shows how a device admin can disable
the ability to record any screen snapshots, and how an audio app can prevent
other apps from recording the content it plays.

## How to handle a `MediaProjection` token

The [`MediaProjection`](https://developer.android.com/reference/android/media/projection/MediaProjection) API
allows apps to acquire a `MediaProjection` token that gives them one time access
to capture screen contents or audio. The Android OS asks the user for their
permission before granting the token to your app.

The OS displays the active `MediaProjection` tokens in the Quick Settings UI and
allows users to withdraw access to a token at any time. When this happens the
virtual displays or audio streams associated with the session stop receiving
media streams. Your app must respond appropriately, otherwise it will continue
to record audio silence or a black video stream.

To handle the loss of a token, register a callback on the `MediaProjection`
instance using the
[`registerCallback`](https://developer.android.com/reference/android/media/projection/MediaProjection#registerCallback(android.media.projection.MediaProjection.Callback,%20android.os.Handler))
method, and stop recording when the
[`onStop`](https://developer.android.com/reference/android/media/projection/MediaProjection.Callback#onStop())
method is called.

For more information, see [Media projection](https://developer.android.com/media/grow/media-projection).

## Capture video

See the
[ScreenCapture sample app](https://github.com/android/media-samples/tree/main/ScreenCapture)
to learn how to learn how to use Media Projection API to capture a device's
screen in real time and show it on a SurfaceView.

You can use the [`DevicePolicyManager`](https://developer.android.com/reference/android/app/admin/DevicePolicyManager)
to prevent screen recording. For enterprise accounts (Android for Work), the
administrator can disable the collection of assistant data for the work profile
by using the
[setScreenCaptureDisabled](https://developer.android.com/reference/android/app/admin/DevicePolicyManager#setScreenCaptureDisabled(android.content.ComponentName,%20boolean))
method.

The codelab
[Managing Android Devices Without an App](https://developer.android.com/codelabs/android-management-api#8)
shows how to forbid screenshots.

## Capture audio playback

The [AudioPlaybackCapture API](https://developer.android.com/guide/topics/media/playback-capture) was introduced in Android 10. This API
gives apps the ability to copy the audio being played by other apps. This
feature is the analog of screen capture, but for audio. The primary use case is
for streaming apps that want to capture the audio being played by games.

Note that the AudioPlaybackCapture API does not affect the latency of the app whose audio is
being captured.

### Building a capture app

For security and privacy, playback capture imposes some limitations.
To be able to capture audio, an app must meet these requirements:

- The app must have the [`RECORD_AUDIO`](https://developer.android.com/reference/android/Manifest.permission#RECORD_AUDIO) permission.
- The app must bring up the prompt displayed by [`MediaProjectionManager.createScreenCaptureIntent()`](https://developer.android.com/reference/android/media/projection/MediaProjectionManager#createScreenCaptureIntent()), and the user must approve it.
- The capturing and playing apps must be in the same user profile.

To capture audio from another app, your app must build an
[`AudioRecord`](https://developer.android.com/reference/android/media/AudioRecord) object
and add an
[`AudioPlaybackCaptureConfiguration`](https://developer.android.com/reference/android/media/AudioPlaybackCaptureConfiguration)
to it. Follow these steps:

1. Call [`AudioPlaybackCaptureConfiguration.Builder.build()`](https://developer.android.com/reference/android/media/AudioPlaybackCaptureConfiguration.Builder#build()) to build an [`AudioPlaybackCaptureConfiguration`](https://developer.android.com/reference/android/media/AudioPlaybackCaptureConfiguration).
2. Pass the configuration to the `AudioRecord` by calling [`setAudioPlaybackCaptureConfig`](https://developer.android.com/reference/android/media/AudioRecord.Builder#setAudioPlaybackCaptureConfig(AudioPlaybackCaptureConfiguration)).

### Controlling audio capture

Your app can control what types of content it can record, and what other
kinds of app can record its own playback.

#### Constraining capture by audio content

An app can limit which audio it can capture by using these
methods:

- Pass an `AUDIO_USAGE` to [AudioPlaybackCaptureConfiguration.addMatchingUsage()](https://developer.android.com/reference/android/media/AudioPlaybackCaptureConfiguration.addMatchingUsage(int)) to permit capturing a specific usage. Call the method multiple times to specify more than one usage.
- Pass an `AUDIO_USAGE` to [AudioPlaybackCaptureConfiguration.excludeUsage()](https://developer.android.com/reference/android/media/AudioPlaybackCaptureConfiguration.excludeUsage(int)) to forbid capturing that usage. Call the method multiple times to specify more than one usage.
- Pass a UID to [AudioPlaybackCaptureConfiguration.addMatchingUid()](https://developer.android.com/reference/android/media/AudioPlaybackCaptureConfiguration.addMatchingUid(int)) to only capture apps with a specific UID. Call the method multiple times to specify more than one UID.
- Pass a UID to [AudioPlaybackCaptureConfiguration.excludeUid()](https://developer.android.com/reference/android/media/AudioPlaybackCaptureConfiguration.excludeUid(int)) to forbid capturing that UID. Call the method multiple times to specify more than one UID.

Note that you cannot use the `addMatchingUsage()` and `excludeUsage()` methods
together. You must choose one or the other. Likewise, you cannot use `addMatchingUid()` and `excludeUid()`
at the same time.

### Constraining capture by other apps

You can configure an app to prevent other apps from capturing its audio.
The audio coming from an app can be captured only if the app meets these requirements:

#### Usage

The player producing the audio must [set its usage](https://developer.android.com/reference/android/media/AudioAttributes.Builder#setUsage(int))
to [`USAGE_MEDIA`](https://developer.android.com/reference/android/media/AudioAttributes#USAGE_MEDIA),
[`USAGE_GAME`](https://developer.android.com/reference/android/media/AudioAttributes#USAGE_GAME), or
[`USAGE_UNKNOWN`](https://developer.android.com/reference/android/media/AudioAttributes#USAGE_UNKNOWN).

#### Capture policy

The player's capture policy must be
[`AudioAttributes.ALLOW_CAPTURE_BY_ALL`](https://developer.android.com/reference/android/media/AudioAttributes#ALLOW_CAPTURE_BY_ALL),
which allows other apps to capture playback. This can be done in a number of ways:

- To enable capture on all players, include `android:allowAudioPlaybackCapture="true"` in the app's `manifest.xml` file.
- You can also enable capture on all players by calling [`AudioManager.setAllowedCapturePolicy(AudioAttributes.ALLOW_CAPTURE_BY_ALL)`](https://developer.android.com/reference/android/media/AudioManager#setAllowedCapturePolicy(int)).
- You can set the policy on an individual player when you build it using [`AudioAttributes.Builder.setAllowedCapturePolicy(AudioAttributes.ALLOW_CAPTURE_BY_ALL)`](https://developer.android.com/reference/android/media/AudioAttributes.Builder#setAllowedCapturePolicy(int)). (If you are using [`AAudio`](https://developer.android.com/ndk/guides/audio/aaudio/aaudio) call [`AAudioStreamBuilder_setAllowedCapturePolicy(AAUDIO_ALLOW_CAPTURE_BY_ALL)`](https://developer.android.com/ndk/reference/group/audio#aaudiostreambuilder_setAllowedCapturePolicy).)

If these prerequisites are met, any audio produced by the player can be captured.
| **Note:** The ability for an app's audio to be captured also depends on the app's `targetSdkVersion`.
|
| - By default, apps that target versions up to and including to Android 9.0 do not permit playback capture. To enable it, include `android:allowAudioPlaybackCapture="true"` in the app's `manifest.xml` file.
| - By default, apps that target Android 10 (API level 29) or higher allow their audio to be captured. To disable playback capture, include `android:allowAudioPlaybackCapture="false"` in the app's `manifest.xml` file.

#### Disabling system capture

The protections permitting capture described above apply only to apps. Android
system components can capture playback by default.
Many of these components are customized by Android vendors and support features
like accessibility and captioning. For this reason it is recommended that apps
allow the system to capture their playback. In the rare case when you do not
want the system to capture your app's playback, set the capture policy to
[`ALLOW_CAPTURE_BY_NONE`](https://developer.android.com/reference/android/media/AudioAttributes#ALLOW_CAPTURE_BY_NONE).

#### Setting policy at runtime

You can call `AudioManager.setAllowedCapturePolicy()` to change the capture
policy while an app is running. If a MediaPlayer or AudioTrack is playing
when you call the method, the audio is not affected. You must close and reopen
the player or track for the policy change to take effect.

#### Policy = manifest + AudioManager + AudioAttributes

Since the capture policy can be specified in several places, it's important
to understand how the effective policy is determined.
The most restrictive capture policy is always applied. For example, an app whose
manifest includes `setAllowedCapturePolicy="false"` will never permit non-system
apps to capture its audio, even if `AudioManager#setAllowedCapturePolicy` is set
to `ALLOW_CAPTURE_BY_ALL`. Similarly, if the
`AudioManager#setAllowedCapturePolicy` is set to `ALLOW_CAPTURE_BY_ALL` and the
manifest sets `setAllowedCapturePolicy="true"`, but the media player's
`AudioAttributes` were built with
`AudioAttributes.Builder#setAllowedCapturePolicy(ALLOW_CAPTURE_BY_SYSTEM)`, then
this media player will not be capturable by non-system apps.

The table below summarizes the effect of the manifest attribute and the
effective policy:

| allowAudioPlaybackCapture | ALLOW_CAPTURE_BY_ALL | ALLOW_CAPTURE_BY_SYSTEM | ALLOW_CAPTURE_BY_NONE |
|---|---|---|---|
| true | any app | system only | no capture |
| false | system only | system only | no capture |