Flutter

One Flutter dependency gives your app an avatar widget. On Android the plugin runs the same engines as the Android SDK, so the avatar renders on the phone: 16 kHz mono speech goes in, and a lip-synced picture comes out as a Flutter Texture.

Before you start

Install

The plugin is published as a tag in the homebrew-bithuman repository. Pin it in pubspec.yaml:

dependencies:
  bithuman:
    git:
      url: https://github.com/bithuman-product/homebrew-bithuman.git
      path: packages/flutter-plugin
      ref: flutter-plugin-v2.6.21

Then run flutter pub get. On Android, Gradle resolves ai.bithuman:essence2-android and ai.bithuman:expression2-android from Maven Central; nothing else to fetch.

For an iOS or macOS build, three more steps:

1. Run the plugin’s scripts/bootstrap.sh once. It downloads the published engines and checks their sha256. For a git dependency, the plugin’s folder is packages/flutter-plugin under ~/.pub-cache/git/homebrew-bithuman-….
2. Raise the deployment targets: platform :ios, '16.0' in ios/Podfile, platform :osx, '13.0' in macos/Podfile, and the Runner targets to match.
3. On macOS only: brew install llama.cpp onnxruntime. The plugin links both.

Authenticate

The engines check your API secret when an avatar loads: pass it to BithumanAvatar.load(…, apiSecret:). The example app asks for it on first launch and keeps it in the Android Keystore, or you can pass --dart-define=BITHUMAN_API_SECRET=… when you build. A shipped app holds the secret on the device, so give each app its own secret that you can rotate or revoke (API secrets).

Credits pay for active session time, talking or idle, billed to the second (pricing).

First frame

Build the example app for your phone, with the wise-pup sample avatar:

git clone https://github.com/bithuman-product/bithuman-examples.git
cd bithuman-examples/app/avatar_chat
flutter pub get
flutter run --release --dart-define=AGENT_CODE=A23WJF0199

Complete example

The avatar_chat app is a complete voice conversation with idle motion and interruption, in one layout for every platform. From plugin 2.6.20 its voice session connects through bitHuman’s realtime relay with your API secret; no token is minted.

Integrate into your app

The avatar is a Texture in your widget tree. On Android the first argument to load is the agent code:

// excerpt: app/avatar_chat/lib/main.dart (bithuman-examples)
import 'package:bithuman/bithuman.dart';

await BithumanAvatar.setExpression2AgentDir('A23WJF0199');
final avatar = await BithumanAvatar.load('A23WJF0199', engine: 'expression2', apiSecret: secret);

Texture(textureId: avatar.textureId);   // the avatar in your layout
avatar.pushAudio(pcm);                   // Int16List, 16 kHz mono speech
avatar.interrupt();                      // cut the current reply
await avatar.dispose();                  // release the engine

Platform notes

• Two models in one app: essence2-android needs minSdk 29; raise the app to 29.
• Your own voice pipeline: any speech your stack produces works, as 16 kHz mono PCM through pushAudio.
• Versions: each plugin tag fixes the Android SDK versions it uses. The current tag and its line are on Downloads & versions.

Performance

The plugin runs the Android SDK’s own engines (the same native libraries), so the Android rows apply:

Troubleshooting

Reference

• Android: the engines under the plugin, their API and their settings.
• avatar_chat example and the plugin source.
• Changelog and Downloads & versions.