Build an Android app

Stream audio into an Android avatar and show its frames in your app.

Integrate into your app

In a live conversation, keep one avatar open and stream into it.

Job	Expression 2	Essence 2
Audio in	16 kHz mono `FloatArray`, −1 to 1	16 kHz mono 16-bit little-endian PCM `ByteArray`
Stream audio as it arrives	`feed(chunk)` per chunk	`feed(chunk)` per chunk
Show frames	`pull(bitmap)`, 20 a second	`pull(buffer)`, 25 a second
End of a reply	`flushTail()`	`endOfAudio()`
Idle between replies	`avatar.idleLoop?.next(bitmap)`	`idle(buffer)`
Interrupt the reply	`resetState(true)`	`resetAudio()`
Check the session	`Expression2Exception` from `create` or `pull`	`Essence2MeteringRefused` from `pull`/`idle`; `checkRender()` throws `Essence2RenderFailed` if the engine stopped
Close it	`close()`	`close()`

To feed the microphone, declare <uses-permission android:name="android.permission.RECORD_AUDIO"/> in your manifest and ask for it at runtime (ActivityResultContracts.RequestPermission) before you start AudioRecord; without it the buffers are silent. The SDKs need only INTERNET, which their AARs merge in for you.

Resample 24 kHz speech (OpenAI Realtime’s) to 16 kHz, and close the avatar when the app leaves the screen: Companion app.

After your API secret is accepted, a network loss does not stop the session for 5 minutes of rendered video. After that, render calls throw a retryable exception until the connection returns. Usage is reported to your account when it does.

For a Flutter app, the Flutter plugin wraps these engines.

Complete example

Two apps you can clone and run on a phone, each with idle motion between replies:

Android Expression 2: the wise-pup sample avatar.
Android Essence 2: the sofia-ramirez sample avatar at full resolution.

Platform notes

Release builds: isMinifyEnabled = true needs nothing extra. Both AARs ship their own keep rules.
Two models in one app: essence2-android needs minSdk 29. Raise the app to 29, or put each model in its own module.
Threads: download and create() on a background thread. The first download is the size shown above, into app-private storage.
Check the version you resolved: Gradle keeps an exact version, so read it back when behaviour differs from this page.
```
./gradlew :app:dependencies --configuration releaseRuntimeClasspath | grep ai.bithuman
```
Private avatars: an avatar you created downloads with the secret you set with Expression2Credential.set or Essence2Credential.set; there is nothing else to pass.

Reference

Android API reference: every public class in both AARs.
Examples: Expression 2 · Essence 2, complete apps you can clone.
Flutter: the Flutter plugin, built on these engines.
Changelog and Downloads & versions.
FFmpeg in essence2-android is LGPL: relink materials.